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The Neurobiology
of Learning and Memory
SECOND EDITION
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The Neurobiology of
Learning and Memory
JERRY W. RUDY
University of Colorado, Boulder
Sinauer Associates, Inc. Publishers
Sunderland, Massachusetts 01375
SECOND EDITION
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About the cover
The image shows a single neuron’s soma and den-
drites (at center, orange) and the dense branches of
its axon (yellow) spreading throughout the entire
dentate gyrus. The overall structure of the mouse’s
hippocampus is outlined in the background in
blue. (Image courtesy of Gyorgy Buzsáki.)
The Neurobiology of Learning and Memory, Second Edition
Copyright © 2014 by Sinauer Associates, Inc.
All rights reserved. This book may not be reproduced in whole or in part
without permission from the publisher.
For information, address
Sinauer Associates, Inc.
P. O. Box 407
Sunderland, MA 01375 U.S.A.
www.sinauer.com
Fax: 413-549-1118
E-mail: publish@sinauer.com
Internet: www.sinauer.com
Library of Congress Cataloging-in-Publication Data
Rudy, Jerry W., 1942-
The neurobiology of learning and memory / Jerry W. Rudy, University of
Colorado, Boulder. -- Second edition.
pages cm
Includes index.
ISBN 978-1-60535-230-5 (hardcover)
1. Memory--Textbooks. 2. Learning--Textbooks. 3. Neurobiology--Textbooks.
I. Title.
QP406.R83 2013
612.8--dc23
2013042526
Printed in U.S.A.
5 4 3 2 1
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The scientific study of learning and memory, originally the domain of psy-
chologists, now is shared by scientists trained in a variety of disciplines that
include biochemistry, cellular–molecular biology, electrophysiology, neuro-
anatomy, and neuropsychology. The work of hundreds of scientists from
these diverse fields has produced an explosion of knowledge about the neu-
robiological basis of learning and memory that almost defies comprehension.
As was the case for the First Edition of this book, this revision represents my
attempt to integrate some of what we have learned from this interdisciplinary
approach into a coherent framework that can be understood by students who
have a rudimentary background in psychology and neuroscience, as well as
by the wider scientific community.
During the seven years separating the two books, the field has continued
to explode with new methods, findings, and ideas. Thus, the challenge of how
to compress an enormous and diverse field into a manageable end product
was even greater for the revision than for the original book. Fortunately, the
general organization of the First Edition provided a framework for achiev-
ing my goal of introducing students to the field without getting lost in too
many details. Nevertheless, my major challenge was trying to decide what to
include, and I am sure that not all will agree with my choices.
Thus, this book is organized into three major sections and written to tell
three large, interrelated, and fascinating stories. This organization results in
telling the tale from the bottom up: it progresses from neurons, synapses, and
molecules that provide the synaptic basis of memories, to the neural systems
that capture the rich content of our experience. Although the organization
remains the same, new chapters have been added to each section, chapters
have been reorganized, and the level of detail has been increased.
The first chapter provides a brief conceptual and historical overview of
the field. Part 1, Synaptic Basis of Memories, introduces the idea that synapses
modified by experience provide the basis for memory storage. It describes
the long-term potentiation methodology used to study how synapses are
Preface
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vi Preface
modified and the concepts needed to understand the organization of syn-
apses. The eight chapters in Part 1 are organized around the idea that the
synaptic changes that support long-term potentiation evolve in four overlap-
ping stages referred to as generation, stabilization, consolidation, and mainte-
nance. The goal of each chapter is to reveal that each stage depends on unique
molecular processes and to describe what they are.
The six chapters in Part 2, Molecules and Memories, build on this foundation
to show how molecules and cellular processes that have been identified from
studies of synaptic plasticity also participate in the making of memories. These
chapters discuss some of the basic conceptual issues researchers face in trying
to relate memory to synaptic molecules and describe some of the behavioral
and neurobiological methods that are used. The chapters describing the pro-
cesses involved in memory formation and consolidation have been extensively
modified to provide a more detailed account of the molecular events that are
engaged to ensure that established memories endure. Both the chapters on
memory modulation (Chapter 13) and the fate of retrieved memories (Chapter
14) have been extensively modified to provide a more in-depth account of the
relevant processes.
The five chapters in Part 3, Neural Systems and Memory, are organized
around the multiple memory systems view—that different neural systems
have evolved to store the content contained in our experiences. This part of
the book features three chapters on the hippocampus (Chapters 15 to 17).
The first of these begins with the story of Henry Molaison (H.M.) to establish
the historical foundation linking the medial temporal hippocampal system to
episodic memory, while the next develops the relationship between the neural
system that supports episodic memory and the indexing theory of how this
is accomplished. The third of these chapters discusses issues that relate this
system to semantic memory, Ribot’s Law (that memories become resistant
to disruption as they age), and systems consolidation. The next two chapters
finish Part 3. Chapter 18 describes the cortico-striatal system and its relation-
ship to what are called behavioral actions and habits, and the final chapter
describes the neural systems involved in the acquisition of emotional memo-
ries and provides an update of current research on how these memories can
be suppressed or removed.
In writing this book, I wanted to provide a broad context in which to intro-
duce the key concepts and facts that are central to a particular topic. I made
no attempt to be comprehensive in the material I covered. Instead, I tried to
maintain a level of description and discussion that was sufficient to ensure a
basic understanding of the relevant principles and processes, without reach-
ing a level of detail that would be tedious. If this approach proves successful,
then I will have provided the reader with a foundation to continue an in-depth
00_RUDY2E_FM.indd vi 10/18/13 12:43 PM

Acknowledgments vii
exploration of this field, while presenting some of the remarkable achieve-
ments of many wonderful researchers who have made this field one of the
great scientific adventures of our time.
Acknowledgments
I am most grateful to the many scientists who have helped to create the field
this book represents, and I regret that I didn’t have the space to represent more
of their great accomplishments. This revision also benefited greatly from inter-
actions with the many undergraduates who were enrolled in my course over
the past five years. Their questions and discussions motivated me to write
the Second Edition. I thank Professor Ryan Bachtell for serving as a sounding
board for some of the new material and his thoughtful input.
I thank Sydney Carroll, Editor, for her encouragement to undertake this
project and Sinauer Associates for supporting a Second Edition of this book.
The preparation of this book benefited greatly from the staff at Sinauer Associ-
ates. I would like to thank Chelsea Holabird for steering the book through the
production process, and Chris Small, Janice Holabird, and Elizabeth Morales
for their talented design ideas, book layout, and artwork.
Once again my wife, Julia A. Rudy, assumed major editorial responsibility
for the final product. Without Julie’s involvement, I cannot imagine how this
project would have been completed. Her editorial skills and commitment to
excellence are directly responsible for the book’s organizational clarity and
readability.
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About the Author
Jerry W. Rudy is College Professor of Distinction in the Department
of Psychology and Neuroscience at the University of Colorado,
Boulder. He received his Ph.D. in psychology from the University
of Virginia in 1970, and joined the CU Boulder faculty in 1980.
The author of over 150 peer-reviewed research papers and book
chapters, Dr. Rudy has served on the editorial boards of the Journal
of Experimental Psychology: Animal Behavior Processes, Psychobiology,
Developmental Psychobiology (Editor in Chief), Behavioral Neuroscience,
Neuroscience & Biobehavioral Reviews, Learning and Memory, and
Neurobiology of Learning and Memory (Associate Editor). He also
served on the governing board and as President of the International Society
for Developmental Psychobiology. He has received grant support from
the National Science Foundation, the National Institute of Mental Health,
and the National Institute of Health. Professor Rudy’s research interests
center on learning and memory processes. His research focused primarily
on understanding the complementary contributions the hippocampus
and neocortex make to learning and memory and the influence immune
products have on memory. He is currently the director of the undergraduate
neuroscience program at the University of Colorado, Boulder.
viii About the Author
Jerry W. Rudy
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Table of Contents
Introduction: Fundamental Concepts
1 and Historical Foundations 1
Learning and Memory Are Theoretical Concepts 2
Psychological and Neurobiological Approaches 3
Psychological Approach 3
Neurobiological Approach 5
Historical Influences: The Golden Age 6
Phenomena and Ideas 6
The Neuron Doctrine and Synaptic Plasticity 9
Behavioral Methods 11
Core Themes 13
Synaptic Plasticity 14
Molecules and Memory 14
Memory Systems 14
Summary 15
References 15
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x Contents
Mechanisms of Synaptic Plasticity:
2 Introduction 19
Two Approaches to Studying Synapses
that Support Memory 20
Simple System: The Gill Withdrawal Reflex 20
Long-Term Potentiation in the Hippocampus 24
The Conceptual Basis and Methodology of LTP 27
Understanding the Field EPSP 29
What is Synaptic Strength? 35
Inducing and Measuring LTP 36
Long-Term Depression: The Polar Opposite of LTP 39
Summary 40
References 40
Modifying Synapses:
3 Central Concepts 43
The Synapse as a Biochemical Factory 44
Postsynaptic Density 44
Other Synaptic Proteins 46
Signaling Cascades 46
First and Second Messengers 46
Protein Kinases and Phosphatases 47
Glutamate Receptors Are Critical to the Induction of LTP 48
LTP Induction Requires Both NMDA and AMPA Receptors 49
Two Events Open the NMDA Channel 51
Increasing AMPA Receptors Supports the Expression of LTP 53
PART 1
Synaptic Basis of Memories 17
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Contents xi
An Organizing Framework: Three Principles 54
The Duration of LTP Can Vary 55
Molecular Processes Contribute to LTP Durability 56
Synapses Are Strengthened and Maintained in Stages 57
Summary 57
References 58
Generating and Stabilizing the Trace:
4 Post-Translation Processes 59
Generating the Trace 60
Dynamics of AMPA Receptor Membrane Trafficking 61
Dynamics of Actin Regulation 65
Generating the Trace: Summary 68
Stabilizing the Trace 68
Parallel Signaling Cascades Regulate Actin Dynamics 71
Cell Adhesion Molecules Help Stabilize the Trace 74
Summary 79
References 79
Consolidating Synaptic Changes:
5 Translation and Transcription 83
The De Novo Protein Synthesis Hypothesis 84
The Genomic Signaling Hypothesis 88
Synapse-to-Nucleus Signaling 88
Soma-to-Nucleus Signaling 90
Translating Protein Requires Increased Calcium Levels 92
Extracellular and Intracellular Sources of Calcium 94
Recruiting Multiple Calcium Sources Increases LTP Duration 97
Summary 99
References 100
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xii Contents
6 Specific Mechanisms 103
Activation of Local Protein Synthesis 104
The mTOR–TOP Pathway 104
The BDNF–TrkB Receptor Pathway 104
Synthesis of a Key New Protein: Arc 106
Arc Antisense Blocks Long-Lasting LTP 106
BDNF-TrkB Consolidation Depends on Arc 107
Arc Sustains Actin Regulation 108
Confirming the Role of Actin Regulation 108
Contribution of Single-Spine Imaging Studies 109
Distinct Actin Pools Regulate Spine Growth 111
Targeting Plasticity Products 113
Protein Degradation and LTP 116
The Ubiquitin Proteasome System 116
Protein Degradation Influences Three Phases of LTP 117
Compartment-Specific Protein Degradation 120
Summary 121
References 123
7 Maintaining the Consolidated Trace 127
PKMζ: A Promising Maintenance Molecule 129
Inhibiting PKMζ Prevents LTP Maintenance 130
PKMζ Releases and Maintains GluA2 AMPA Receptors 132
Two Key Contributions of PKMζ 134
Trapping PKMζ 134
Genetic Engineering Reveals Additional
Maintenance Molecules 136
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Contents xiii
Summary 137
References 138
8 Toward a Synthesis 139
Generation 139
Stabilization 141
Consolidation 142
Maintenance 143
Issues and Implications 143
The Importance of Actin Regulation 143
Synaptic Plasticity and Memory 145
Summary 148
References 149
Making Memories:
9 Conceptual Issues and Methods 153
LTP and Memory 154
Behavior and Memory 154
Test Behavior: The Window to the Memory Trace 155
The Learning–Performance Distinction 157
Dimensions of Memory Traces 158
The Concept of Memory Consolidation 159
PART 2
Molecules and Memories 151
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xiv Contents
Electroconvulsive Shock and Memory Disruption 160
Memory Disruption: A Storage or Retrieval Failure? 160
Some Behavioral Test Methods for Studying Memory 161
Inhibitory Avoidance Conditioning 162
Fear Conditioning 163
Spatial Learning in a Water-Escape Task 164
Why These Three Behavioral Test Methods? 167
Methods for Manipulating Brain Function 167
Stereotaxic Surgery 167
Genetic Engineering 169
Summary 172
References 173
Memory Formation:
10 Early Stages 175
NMDA Receptors and Memory Formation 176
Pharmacological Alteration 177
Genetic Engineering 177
Cautions and Caveats 182
AMPA Receptors and Memory Formation 184
Fear Conditioning Drives GluA1 AMPA Receptors into Spines 185
Preventing AMPA Receptor Trafficking Impairs Fear
Conditioning 185
Ampakines and Cognitive Enhancement 188
NMDA and AMPA Receptors: Acquisition and Retrieval 189
CaMKII and Memory Formation 191
Preventing Autophosphorylation of CaMKII Impairs Learning 192
CaMKII and Fear Memories 193
Actin Dynamics and Memory Formation 194
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Contents xv
Working and Reference Memory Depend on Glutamate
Receptors 195
An Animal Model 196
Glutamate Receptor Composition Is Critical to Working
Memory 197
Summary 199
References 200
11 Memory Consolidation 205
The Research Paradigm 207
Transcription and Enduring Memories 208
The Importance of CREB 209
Some Memory Genes 213
Summary of Transcription 215
Translation and Enduring Memories 216
The De Novo Protein Synthesis Hypothesis 216
Methodological Issues 217
Multiple Rounds of Protein Synthesis 219
Protein Degradation Processes 226
Defining the Consolidation Window 227
Summary 228
References 229
Memory Maintenance
12 and Forgetting 233
PKMζ and Memory Maintenance 234
Interfering with PKMζ Erases a Taste-Aversion Memory 234
PKMζ Strengthens New Memories and Prevents Forgetting 235
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xvi Contents
PKMζ KO Mice Learn and Remember 235
Interpretive Caveat 236
Toward a Neurobiology of Forgetting 236
Summary 238
References 239
13 Memory Modulation Systems 241
Memory Modulation Framework 242
The Great Modulator: The Basolateral Amygdala 244
The Role of Epinephrine 246
The Epinephrine Vagus Connection 248
Norepinephrine Enhances Memories 251
Norepinephrine Enhances Glutamate Release
and Arc Translation 252
The Norepinephrine Signal in Other Storage Areas 254
The Epinephrine Liver–Glucose Connection 255
Bioenergenics and the Brain 255
Glucose Modulates Memory 255
Glucose and Aging 256
Glucose and Transcription 257
Glucocorticoids: The Other Adrenal Hormones 259
Summary 260
References 261
14 The Fate of Retrieved Memories 265
Reactivated Memory Disrupted by ECS 266
Active Trace Theory 266
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Contents xvii
Reconsolidation Theory 268
Assessing Reconsolidation Theory 271
How Does Reactivation Destabilize the Trace? 272
Trace Restabilization and Trace Updating 275
Memory Erasure: A Potential Therapy 277
Preventing Drug Addiction Relapse 277
Eliminating Debilitating Fears 280
Stepping Back: Boundary Conditions 280
Summary 281
References 281
Memory Systems and
15 the Hippocampus 287
The Multiple Memory Systems Perspective 288
Example 1: Personal Facts and Emotions 288
Example 2: Personal Facts and Skills 289
The Case of Henry Molaison 290
The Episodic Memory System 292
The Animal Model Strategy 294
Studies of Patients with Selective Hippocampal Damage 296
The DNMS Paradox Resolved 298
Summary 299
References 299
PART 3
Neural Systems and Memory 285
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xviii Contents
The Hippocampus Index
16 and Episodic Memory 303
Properties of Episodic Memory 304
Conscious Recollection and Contextual Information Storage 304
Automatic Capture of Episodic and Incidental Information 305
Single Episode Capture with Protection from Interference 305
Properties Summary 306
A Neural System that Supports Episodic Memory 306
The Hierarchy and the Loop 306
The MTH System 308
The Indexing Theory of Episodic Memory 309
The Hippocampus Does Not Store Content 311
Pattern Completion and Pattern Separation 311
Why Not Just Store the Memory in the Neocortex? 312
Indexing Theory and Properties of Episodic Memory 313
Evidence for the Indexing Theory 314
Animal Studies 315
Shining Light on The Index 321
Summary 323
References 324
The MTH System: Episodic Memory,
17 Semantic Memory, and Ribot’s Law 327
A Modular MTH System 329
Growing Up without the Hippocampus 329
Recognition Memory and MTH Modularity 331
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Contents xix
The MTH System and Ribot’s Law 332
The Standard Model of Systems Consolidation 333
Challenges to the Standard Model 336
Multiple Trace Theory 339
Other Evidence Relevant to the Debate 340
Ribot’s Law Revisited: Summary 346
Summary 347
References 348
Actions, Habits, and the
18 Cortico-Striatal System 353
The Concept of Instrumental Behavior 354
Two Theories of Instrumental Behavior 356
Thorndike’s Law of Effect 356
Tolman’s Cognitive Expectancy Theory 356
Action and Habit Systems 358
With Practice, Actions Become Habits 361
A Conceptual Model for Actions and Habits 363
Action and Habit Systems Compete 364
Action Systems Are Vulnerable 365
A Cortico-Striatal System Supports Instrumental
Behavior 366
Neural Support for Actions 368
Neural Support for Habits 371
The Striatum Stores Action and Habit Memories 372
The Neural Basis of Rewarding Outcomes 374
Summary 376
References 376
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xx Contents
Learning about Danger: The
19 Neurobiology of Fear Memories 379
The Fear System 380
The Neural Basis of Fear 382
Eliminating Dangerous Fears: Theories of Extinction 386
Neural Basis of Fear Extinction 389
The CS–noUS Neural Circuit 389
Why Fear Renews: A Role for the Hippocampus 389
Extinction Learning Depends on NMDA Receptors 391
New Insights: Extinction Can Erase Fear Memories 393
Extinction and Reconsolidation 394
Summary 395
References 396
Photo Credits 399
Glossary 401
Author Index 415
Subject Index 423
00_RUDY2E_FM.indd xx 10/18/13 12:43 PM

Our uniqueness as human beings derives in large part from evolutionary
adaptations that permit experience to modify connections linking networks
of neurons in the brain. Information conveyed into the brain by our sensory
channels can leave a lasting impression on neural circuits.These networks not
only can be modified, the information contained in the modifications can be
preserved and later retrieved to influence our behavior. Our individual experi-
ences act on these networks to make us who we are.We have the ability to
learn a vast array of skills: we can become musicians, athletes, artisans, skilled
craftsmen, or cooks. Experience tunes our emotions to our environments.We
acquire food preferences and aversions. Incredibly, without intention, we also
lay down an autobiographical record of the events, times, and places in which
our experiences occur.We are connected with our past and can talk about it.
We learn and we remember.
Introduction:
Fundamental Concepts
and Historical Foundations
1
01_RUDY2E_Chapter01.indd 1 10/18/13 11:24 AM

2 Chapter 1
Historically, the study of learning and memory has been the domain of phi-
losophers and psychologists who have defined the relevant phenomena and
many of the important variables that influence them. Only recently have brain
scientists seriously weighed in on this topic. Armed with sophisticated meth-
ods to measure and manipulate brain processes and conceptual frameworks
to guide their application, neurobiologists have now made enormous inroads
into the mystery of how experience modifies the brain.
Consequently, an important field now exists called the neurobiology of
learning and memory. Scientists working in this field want to know how the
brain stores and retrieves information about our experiences. The goal of this
book is to present an account of some of the major accomplishments of this
field and to provide a background that will facilitate the understanding of
many of the issues and central assumptions that drive research in this field.
Learning and Memory Are Theoretical Concepts
The terms “learning” and “memory” are often used as if they are directly
observable entities, but they are not. Learning and memory are theoretical con-
cepts used to explain the fact that experience influences behavior (Figure 1.1). A
familiar example will suffice to make the point.
You have an exam tomorrow. So, over the next few hours you closet
yourself with your books and class notes. You take the test and answer the
questions to the best of your knowledge. Later you receive your grade, 90%.
Assuming that your grade would have been 50% if you had not studied,
then a reasonable person (the professor) would assume that you learned and
remembered the information needed to pass the test. The key phrase here is
“would assume.” Learning and memory were never directly observed. The
only directly observable events in this example are that (a) you spent time
with your notes and books, and (b) you took the test and performed well. That
you learned and remembered is inferred from your test performance and the
professor’s knowledge that you studied.
Figure 1.1
Learning and memory are unobservable, inferred processes used to explain the fact
that our past experience influences our behavior.
Experience
observable
Behavior
observable
Learning–memory
inferred
Learning and memory are theoretical concepts

Introduction 3
Larry Squire (1987) provided a useful definition of the terms learning
and memory: “Learning is the process of acquiring new information, while
memory refers to the persistence of learning in a state that can be revealed at
a later time” (p. 3). Other, more restrictive definitions have been proposed.
They usually also stipulate what learning and memory are not. For example,
a restricted definition would appropriately exclude fatigue, maturation, and
injury that might result from or be associated with experience.
Although learning and memory are theoretical concepts, neurobiologists
are motivated by the belief that they have a physical basis in the brain. A
slight modification of Squire’s definition provides a useful definition of the
field: the goal of neurobiologists working in this field is to understand how
the brain acquires, stores, and maintains representations of experience in
a state that permits the information contained in the representation to be
retrieved and influence behavior.
Psychological and Neurobiological Approaches
The study of learning and memory is the domain of both psychology and
neurobiology. It is useful to point out some fundamental differences between
the two approaches.
Psychological Approach
The general goal of psychology is to (a) derive a set of empirical principles
that describe how variation in experience influences behavior, and (b) pro-
vide a theoretical account that can explain the observed facts. The study of
memory became a science when Hermann Ebbinghaus developed the first
methods for assessing the acquisition and retention of a controlled experience.
He recognized that to study “pure memory” required a methodology that
could separate what the subject already has learned from what the
subject is now being asked to remember (Ebbinghaus, 1913). To do
this, he invented what are called nonsense syllables. A nonsense
syllable consists of a vowel placed between two consonants, such as
nuh, vag, or boc. These syllables were designed to be meaningless so
they would have to be learned without the benefit of prior knowl-
edge. Thus, for example, dog, cat, or cup would be excluded. Ebb-
inghaus made up hundreds of nonsense syllables and used them to
produce lists that were to be learned and remembered. Among the
task variables he manipulated were factors such as the number of
times a given list was presented during the memorization phase and
the interval between the learning and the test phase. Hermann Ebbinghaus

4 Chapter 1
Ebbinghaus worked alone and was the only subject of his experiments.
He found that his test performance increased the more he practiced a given
list. He also documented the fact that retention performance was better when
he spaced the repetition of a given list than when the list was repeated with-
out inserting a break between the learning trials. He also documented the
first “forgetting curve.” As is illustrated in Figure 1.2, retention was excellent
when the test was given shortly after the learning trial, but it fell off dramati-
cally within the first hour. Remarkably, the curve stabilized thereafter.
Empirical principles such as those produced by Ebbinghaus’s experiments
led to theoretical questions about the underlying structure of the memory
(Figure 1.3). Consider Ebbinghaus’s forgetting curve. One could imagine that
Percent
recalled
1 min 1 h 24 h 5 d
nuh vag boc
10 d 30 d
0
Retention interval
25
50
75
100
0
Figure 1.2
Ebbinghaus documented the
first forgetting curve. Note that
substantial forgetting occurs in
the first hour after learning, but
thereafter recall is fairly stable.
Trace
strength
Trace
strength
Single trace Dual trace
Time
Time
Short-term trace
Long-term trace
Figure 1.3
The single-trace theory explains Ebbinghaus’s forgetting curve by assuming that the
strength of a single memory trace declines monotonically as a function of time between
learning and the retention test. The dual-trace theory explains that the forgetting curve
results from two memory traces whose strength decays at different rates.

Introduction 5
this behavioral function is a direct reflection of the property of a single mem-
ory trace, the strength of which declines monotonically as a function of the
retention interval. In essence, the behavioral function directly represents the
decay properties of the memory trace. Another theorist looking at the same
data might be struck by the fact that although the rate of forgetting is initially
rapid there is very little change after the first hour. This theorist might pro-
pose that the forgetting curve is a product of two memory traces with differ-
ent decay rates: a short-term memory trace that decays relatively rapidly and
a long-term memory trace that has a much slower decay rate. Note in both
cases hypotheses are put forth that point to properties—memory strength
and memory traces with different decay rates—that defy direct observation.
A fundamental feature of the traditional psychological approach is that a
single methodology is used to collect the data and to test theory. Psycholo-
gists do not directly manipulate or measure brain function. They vary only
the nature of experience and measure only behavior (Figure 1.4). Thus the
psychological approach can be described as operating at a single level of
analysis. Psychological research has identified critical phenomena and con-
cepts that provide the starting point for neurobiological investigation.
Neurobiological Approach
Psychologists study only the relationship between experience and behavior.
Neurobiologists study how experience influences memory-dependent behav-
ior by its influences on brain systems, synapses, and molecules.
Psychological
approach
Experience
Neurobiological
approach
Experience
Brain systems
Synapses
Molecules
Behavior
Behavior
Figure 1.4
Psychologists study only the relation-
ship between experience and behavior.
Neurobiologists study how experience influ-
ences memory-dependent behavior by its
influences on brain systems, synapses, and
molecules.

6 Chapter 1
The goal of neurobiology is to relate the basic facts of learning and memory
to events happening in the brain. If, in the above example, the dual-trace
theory was established as valid by psychological experiments, the neurobi-
ologist would want to know what are the properties of the brain that support
two different memory traces. This goal requires a multi-level approach. In
addition to using the behavioral methods of psychology that reveal how task
variables such as trial spacing and repetition influence learning and retention,
the neurobiological approach requires methods for:
• determining the regions of the brain that make up the brain system
supporting the memory;
• determining how synapses that are potential storage mechanisms are
altered by experience; and
• manipulating and measuring molecules in neurons that ultimately
support the memory.
Thus, the neurobiological approach is an interdisciplinary, multi-level
approach. It combines the behavioral methods of psychology with the meth-
ods of anatomy, electrophysiology, pharmacology, biochemistry, and genet-
ics. Because the methodologies of each discipline are complex and require
specialized training to learn, different scientists often combine their individ-
ual skills to attack the problem.
Historical Influences: The Golden Age
The full-scale application of neurobiological methods to the study of learning
and memory is a relatively new development. However, many of the important
phenomena, concepts, insights, and methods that drive the field emerged over
100 years ago. Thirty-seven years ago, in his comprehensive review of the psy-
chobiology of memory, Paul Rozin (1976) described the last decade of
the nineteenth century as the Golden Age of Memory because many
of the basic phenomena and ideas emerged during that period.
Phenomena and Ideas
It was at the beginning of that decade that the French psychologist
Théodule Ribot published his classic Diseases of Memory (1890). He
was motivated by the belief that the study of brain pathology could
provide insights into the normal organization of memory. His stud-
ies of many clinical cases led him to believe that the dissolution of
memory accompanying pathology or injury followed an orderly
Théodule Ribot

Introduction 7
temporal progression. He proposed that recent memories are the first to be
lost, followed by autobiographical or personal memories that also have a tem-
poral gradient (Figure 1.5). He believed that habits and emotional memories
were the most resistant to dissolution. Ribot’s insight anticipated the modern
development of the multiple system perspective that is discussed in Chapter
15. This is because his insight implies that there are different categories of
memory and they are supported by different neural systems.
The idea that there is a temporal progression to memory loss—that old
memories are more resistant to disruption than new ones—is often referred
to as Ribot’s Law (see Figure 1.5). This generalization begs the ques-
tion, what is it about old memories that makes them resistant to disrup-
tion? This question, which remains at the center of contemporary
research and is the source of both excitement and controversy, is
more fully discussed in Chapter 17.
It was also during this period that Sergei Korsakoff (1897)
described the amnesic syndrome that now bears his name. Patients
with this syndrome display what would now be called a severe,
anterograde amnesia. They are not able to remember events experi-
enced after the onset of the syndrome. However, early in the disease,
memories established before the onset of the syndrome are generally
preserved. Thus, they initially display very little retrograde amnesia.
Resistance
to
disruption
New Old
Age of the memory
Recent
memories
(A) The Dissolution of Memory
Personal
memories
(B) Ribot’s Law
Habits,
skills
Emotional
memories
Figure 1.5
(A) Ribot believed that after
a brain pathology or injury
the dissolution of memory
followed an orderly temporal
progression. Recent memories
are the first to be lost,
followed by autobiographical
or personal memories that
also have a temporal gradient.
He believed that habits and
emotional memories were the
most resistant to dissolution.
(B) Ribot proposed that older
memories are more resistant
to disruption by traumatic
events than newer memories.
This hypothesis is called
Ribot’s Law.
Sergei Korsakoff

8 Chapter 1
Korsakoff believed that the primary defect was an inability to form new
memories. His interpretation of the deficit included two ideas. One idea was
that the pathology impaired the physiological processes needed to establish
and retain the memory. Today one might say that the mechanisms of memory
storage or consolidation are impaired. The second idea was that the pathology
in some way weakened the associative network that contained the memory
or, in modern terms, produced a retrieval deficit, that is, the core memory
trace is established but cannot be accessed. Korsakoff believed both factors
contributed to the syndrome. Whether memory impairment is the result of
a storage or retrieval failure can still be the source of heated debate in the
contemporary literature.
One can only marvel at the insights contained in William James’s
Principles of Psychology (1890). An often noted contribution was his
conception of memory as a sequence of processes initiated by an
experience that begins with a briefly lasting sensation he called after
images, then to the stage he called primary memory, and to the final
stage he called secondary memory or memory proper (Figure 1.6).
Primary memory was viewed as the persisting representation
of the experience that forms part of a stream of consciousness.
Secondary memory contained the vast record of experiences that
had receded from the stream of consciousness but could be later
retrieved or recollected: “It is brought back, fished up, so to speak,
from a reservoir in which, with countless other objects, it lay bur-
ied and lost from view” (James, 1890, p. 646). An object in primary
William James
Trace
strength
Experience
Time
After
image
Primary
memory
Secondary
memory
Figure 1.6
William James proposed that memories
emerge in stages. The after image is
supported by a short-lasting trace, then
replaced by the primary memory trace.
Secondary memory is viewed as the
reservoir of enduring memory traces.

Introduction 9
memory is not brought back: it was never lost. Thus, we have the roots of
the modern distinction between short-term memory and long-term memory
that remain central to modern investigations of the neurobiological bases of
memory.
James devoted an entire chapter to the brain. However, the absence of any
relevant information precluded an attempt to directly relate memory phe-
nomena to any specific regions of the brain or mechanisms. Nevertheless, he
strongly believed that the retention of experience was not a mysterious men-
tal property but that “it was a purely physical phenomenon, a morphological
feature . . .” (p. 655). He even provided a connectionist model of the memory
trace to bolster his belief. In at least two places he used the term plasticity to
describe the property of the brain that allows it to be modified by experience.
For example, in his discussion of memory he wrote, “What happens in the
nerve-tissue is but an example of that plasticity or of semi-inertness, yield-
ing to change . . .” (p. 655). Thus, modern developments would come as no
surprise to him.
The Neuron Doctrine and Synaptic Plasticity
During this era, the foundation for modern neuroscience—the neuron doc-
trine—emerged (see Shepard, 1991). Camillo Golgi had developed a method
(now called the Golgi Stain) that allowed what came to be called neurons to
be visualized. However, there was debate about how these elements were
organized to support brain function.
A prominent idea that was backed by Golgi was called reticulum (network)
theory. According to this theory the nervous system represented an exception
to cell theory—the idea that the fundamental element in the structure of living
bodies is a cell. Instead, nerve tissue was organized into a continuous network
rather than discrete independent units. Golgi believed that the branches from
the cell body we now call dendrites were in contact with blood vessels and
functioned only to provide nutrients to the cell. The business end of
the nerve cells was carried out by what are now called axons, which
he believed were continuous (fused) with each other and formed
the reticulum or network (Figure 1.7). A significant problem with
this view is that it prohibits the formulation of a principle for how
transmission between nerve cells could occur.
Many individuals contributed to the dismissal of reticulum the-
ory (Shepard, 1991); however, the great Spanish neuroanatomist
Santiago Ramón y Cajal is generally acknowledged as the most
important opponent of reticulum theory and father of the neuron
doctrine—the idea that the brain is made up of discrete cells called
nerve cells or neurons that are the elemental signal units of the brain Santiago Ramón y Cajal

10 Chapter 1
(Ramón y Cajal, 1894–1904). (See Box 1.1 for a list of key elements of the neu-
ron doctrine.) He refined Golgi’s method to increase its reliability and, based
on his anatomical descriptions, forcefully argued that neurons are not fused
but are contiguous (for example, Ramón y Cajal’s 1894 Croonian lecture, par-
tially reproduced in English in Shepard, 1991). This conclusion led to the
now accepted view that neurons are truly independent, genetically derived
units that are composed of (a) the cell body or soma, (b) dendrites, and (c) a
single axon. With this conceptual breakthrough Ramón y Cajal also was able
to figure out the brain’s basic wiring diagram—axons could travel short or
long distances but they always terminated at specific locations among fields
of dendrites. Axon endings were contiguous with dendrites but not continu-
ous (fused) with them. Sir Charles Sherrington (1906) subsequently named
(A) (B)
Figure 1.7
(A) Camillo Golgi. (B) Golgi
developed a method (now
called the Golgi Stain)
that allowed what are
now called neurons to be
visualized. Based on his
observations, he believed
in the reticulum or network
theory of the organization
of nerve tissue.
• The neuron is an anatomical unit—the fundamental structural and functional
unit of the nervous system.
• The neuron is composed of three parts: cell body, dendrites, and axons.
• Neurons are discrete cells, which are not continuous with other cells.
• The points of connection between neurons are called synapses.
• The neuron is a physiological unit. Electrical activity flows through the neuron
in one direction (from dendrites to the axon, via the cell body).
• The neuron is the developmental–genetic unit of the nervous system.
BOX 1.1 Elements of the Neuron Doctrine

Introduction 11
this axon-dendritic junction—the point of contiguity between axons and den-
drites—the synapse. The functional significance of this anatomical arrange-
ment was recognized by Ramón y Cajal in what is called the Law of Dynamic
Polarization, the idea that a neuron receives signals (nerve impulses) at its
dendrites and transmits them via the soma, then along the axon in one direc-
tion—away from the cell body.
At the very heart of contemporary investigations of the mechanisms of
memory storage is the synaptic plasticity hypothesis, which posits that “the
strength of synaptic connections—the ease with which an action potential
in one cell excites (or inhibits) its target cell—is not fixed but is plastic and
modifiable” (Squire and Kandel, 1999, p. 35). However, this hypothesis was
not initially universally embraced. In the 1890s there was a heated debate
as to whether neurons maintained a fixed structure throughout the lifetime
of an individual (see DeFelipe, 2006). Further testimony to Ramón y Cajal’s
brilliance was his position on this issue and his willingness to speculate from
his anatomical descriptions that the points of contiguity between axons and
dendrites (synapses) provide opportunities for modification by experience. In
his theory of cerebral gymnastics he even proposed a model of how this could
happen (see DeFelipe, 2006). Thus, Ramón y Cajal is also acknowledged for
the development of one of the field’s most important ideas.
Behavioral Methods
The Golden Age documented important clinical phenomena that provided
initial insights into memory organization and produced ideas that remain
fundamental to contemporary investigations. Remarkably, this period also
produced some of the essential behavioral methods that in one form or
another continue to be used to study how the brain supports learning and
memory. Ebbinghaus’s contribution already has been discussed. His work
provided the basis for the scientific study of human memory.
Neurobiologists want to understand how the brain supports learning
and memory. Studies of normal people and patients with brain damage
can identify interesting phenomena that can provide some insight into the
organization of memory. However, there are obvious major ethical concerns
that constrain the direct manipulation of the human brain. Thus, to directly
manipulate and measure brain events, neurobiologists have relied extensively
on methods that allow the study of learning and memory with nonhuman
animals. During the Golden Age, Ivan Pavlov and Edward L. Thorndike
developed methodologies that remain essential to contemporary researchers
who study the learning and memory processes of animals.
Pavlov (1927) began his career shift from studying digestive physiology to
investigating the integrative activity of the brain. In doing so, he developed

12 Chapter 1
the fundamental paradigm for studying associative learning and memory
in animals (Figure 1.8). The essence of this methodology, called classical or
Pavlovian conditioning, is that a neutral stimulus such as the ringing of a bell
(called the conditioned stimulus or CS) was paired with a biologically signifi-
cant event such as food (called the unconditioned stimulus or US). The US
caused the dog to salivate; this response is called the unconditioned response
or UR. As a consequence of the several pairings of the bell (CS) and food
(US), simply ringing the bell caused the dog to salivate. The response to the
CS is called the conditioned response or CR. The ability of the CS to evoke
the CR is believed to be the result of the brain associating the occurrence of
the CS and US (Figure 1.9). Today no one uses dogs or measures the salivary
response to study learning and memory in nonverbal animals. However,
Figure 1.8
Pavlov in his laboratory.
Figure 1.9
In the Pavlovian conditioning method, two events called the CS and US are
presented together. Subsequently, the CS evokes the response called the CR.
Psychologists assume that the CS evokes the CR because the CS gets associated
with the US. Psychologists and neurobiologists continue to use this method to study
associative learning in animals.
Before conditioning
CS US UR
After conditioning
Association
CS US CR

Introduction 13
many neurobiologists still use variations of the Pavlovian condition-
ing methodology to study learning and memory in other nonhuman
animals.
It was also during the Golden Age that Thorndike (1898) published
his dissertation on animal intelligence in which he provided a meth-
odology that permitted an objective investigation of how animals
learned the consequences of their action. He invented what is referred
to as Thorndike’s puzzle box (Figure 1.10). An animal such as a cat or
chicken would be placed in a wooden crate and to escape it had to learn
to depress a lever to open an escape door. Thorndike’s experiments
provided the foundation for study of what is now called instrumen-
tal learning or Thorndikian conditioning. Variations of his methods
continue to be extensively employed to reveal the systems of the brain
involved in how animals learn to adapt their behavior based on the
consequences of their actions.
Core Themes
Scientists from a wide range of disciplines have been intrigued by questions
about how the brain supports learning and memory. Their efforts have gener-
ated an enormous literature that even seasoned researchers find overwhelm-
ing. No single book can begin to do justice to the current state of knowledge.
Edward L. Thorndike
Figure 1.10
Edward L. Thorndike invented the methodology for studying what is now called
instrumental learning or Thorndikian conditioning. Cats, dogs, and chickens were
placed into his puzzle box and had to learn how to manipulate levers to escape.

14 Chapter 1
However, it may be possible to provide a road map for appreciating some of
the major accomplishments of this field and provide a foundation for future
study. To achieve this more modest goal, this book is organized around three
large themes that represent much of the field: synaptic plasticity, molecules
and memory, and memory systems.
Synaptic Plasticity
Contemporary neuroscientists believe that the synapse is the fundamental
unit of memory storage. For synapses to support memory they have to be
plastic or modifiable. The last 30 years have yielded remarkable insights into
the molecular processes that are engaged to support changes in the strength
of synapses. Thus, the goal of a major portion of this book is to present many
of the important findings and ideas that have been generated by this field.
Molecules and Memory
Memories result from behavioral experiences. The past 30 years also have
witnessed the development of many useful behavioral procedures for study-
ing memory formation in nonverbal animals. Armed with these behavioral
methods, researchers have been emboldened to determine if memories are a
product of some of the same cellular–molecular events that alter the strength
of synaptic connections. Bringing ideas from the study of synaptic plasticity to
the study of memory formation is one of the most dynamic and exciting adven-
tures in brain–behavioral sciences. Thus, a section of this book describes how
memory researchers have been able to use what has been learned from stud-
ies of synaptic plasticity to begin to uncover the molecular basis of memory.
Memory Systems
The content of our experience matters to the brain. One of the important
achievements of the modern era has been the realization that the brain has
evolved neural systems that are specialized to capture and store the varied
content generated by our experiences. This idea is generally represented by
the term multiple memory systems. For example, different systems have been
identified that enable us to keep track of the episodes that make up our per-
sonal history and to record emotionally charged events to protect us from
danger. These stand apart from other brain systems that enable us to learn
the consequences of our actions and acquire the routine and not so routine
skills and habits that enable us to interact successfully with our environment.

Introduction 15
The last section of this book provides an introduction to some of the important
developments in this domain.
Summary
In this chapter a number of fundamental concepts were described that provide
a background needed to go forward. Some of the historical foundation for the
field was also presented. Many of the core phenomena, concepts, and behav-
ioral methods that are central to the neurobiology of learning and memory
emerged in what Rozin called the Golden Age of Memory, the last decade
of the nineteenth century. These ideas are intimately linked to individuals
(Ebbinghaus, James, Korsakoff, Pavlov, Ramón y Cajal, Ribot, and Thorndike)
who have provided a context from which the central themes that guide con-
temporary research emerged.
References
DeFelipe, J. (2006). Brain plasticity and mental processes: Cajal again. Nature Reviews
Neuroscience, 7, 811–817.
Ebbinghaus, H. (1913). Uber das Gedachtnis: Untersuchungen zur Experimentellen Psy-
chologie. Leipzig: Dunke and Humboldt. Trans. by H. A. Ruger and C. E. Byssennine
as Memory: a contribution to experimental psychology. New York: Dover.
James, W. (1890). Principles of psychology. New York: Holt.
Korsakoff, S. S. (1897). Disturbance of psychic function in alcoholic paralysis and its
relation to the disturbance of the psychic sphere in multiple neuritis of nonalchoholic
origins. Vesin. Psychiatrii 4: fascicle 2.
Pavlov, I. P. (1927). Conditioned reflexes. London: Oxford University Press.
Ramón y Cajal, S. (1894–1904). Textura del sistema nervioso del hombre y de los ver-
tebrados. Trans. by N. Swanson and L. W. Swanson as New ideas on the structure of the
nervous system in man and vertebrates. Cambridge, MA: MIT Press, 1990.
Ramón y Cajal, S. (1894). The Croonian lecture: la fine structure des centres nerveux.
Proceedings of the Royal Society of London, 55, 444–468 (in French).
Ribot, T. (1890). Diseases of memory. New York: Appleton and Company.
Rozin, P. (1976). The psychobiology of memory. In M. R. Rosenzweig and E. L. Ben-
nett (Eds.), Neural mechanisms of learning and memory (pp. 3–46). Cambridge, MA: The
MIT Press.
Shepherd, G. M. (1991). Foundations of the neuron doctrine. New York: Oxford University
Press.

16 Chapter 1
Sherrington, C. S. (1906). The integrative action of the nervous system. New York: Charles
Scribner’s Sons.
Squire, L. R. (1987). Memory and brain. New York: Oxford University Press.
Squire, L. R. and Kandel, E. R. (1999). Memory from mind to molecules. New York: W. J.
Freeman and Company.
Thorndike, E. L. (1898). Animal intelligence: an experimental study of the associative
processes in animals. Psychological Review, Monograph Supplement 2, no. 8.

PART 1
Synaptic Basis
of Memories
CHAPTER 2
Mechanisms of Synaptic Plasticity:
Introduction
CHAPTER 3
Modifying Synapses:
Central Concepts
CHAPTER 4
Generating and Stabilizing the Trace:
Post-Translation Processes
CHAPTER 5
Translation and Transcription
CHAPTER 6
Specific Mechanisms
CHAPTER 7
Maintaining the Consolidated Trace
CHAPTER 8
Toward a Synthesis

What properties of the brain allow it to acquire and maintain information
generated by our experiences? Conventional wisdom is that memories are
stored in large networks of interconnected neurons and that experience
leaves its impact by modifying the connections between those neurons (Teyler,
1999).Thus, neurobiologists are motivated by the belief that the information
content of our various experiences persists in a retrievable form because the
synapses (points of contact between neurons) can be modified by experience.
The strength of an existing connection can be increased or decreased by expe-
rience.As noted in the previous chapter, this synaptic property is known as
plasticity.This was Ramón y Cajal’s (1894–1904) big idea, that synapses are
plastic.
It is unlikely that a single synapse is the fundamental unit of memory, but
many neurobiologists believe that changes in synaptic strength among groups
of neurons can represent experience. This belief has attracted a large number
of scientists to the study of synaptic plasticity and generated an enormous
Mechanisms of Synaptic
Plasticity: Introduction
2

20 Chapter 2
and complex literature. The work of these scientists has yielded some impor-
tant clues about how the brain acquires and stores memories.
The goals of this chapter and several that follow are (1) to present some of
the fundamental concepts and methodologies needed to understand how syn-
apses are modified and (2) to highlight some of the important findings that
provide the clues to how synapses might store memories. Insights into the
mechanisms of synaptic plasticity come from studies of neurons completely
isolated from the organism. Such artificial preparations have proven to be
invaluable to understanding how synapses are modified. However, keep in
mind that any clues derived from the study of synaptic plasticity must be
tested in behavioral experiments before a claim can be made that a synaptic
mechanism supports a memory. Specifically, it must be demonstrated that
this mechanism operates in an intact animal to support the effect an experi-
ence has on a behavior that depends on learning and memory.
Two Approaches to Studying Synapses
that Support Memory
In an ideal world one would like to study how experience actually modifies
the synapses that support a memory. This turns out to be a daunting task
because it requires locating that memory trace (also called the engram) and
its natural sensory inputs.
Karl Lashley (1950) is generally credited with mounting the first serious
attempt to locate the memory trace. His attempt was unsuccessful and dis-
couraging. Workable approaches to this problem, however, began to emerge
in the late 1960s. One of these, sometimes called the simple system approach,
emerged from a deliberated strategy, while another emerged from a discov-
ery called long-term potentiation (LTP) in a region of the brain called the
hippocampus. These approaches are described below.
Simple System: The Gill Withdrawal Reflex
Biologists believe that the answer to a big question often can be found by
reducing the problem to its most elementary form. If you believe that a mem-
ory trace is created when experience modifies some synaptic connections,
then you need an animal with the simplest nervous system that can sup-
port a modifiable behavior. In this case you would be willing to sacrifice the
complexities of the human brain and the richness of the memories it can sup-
port to gain other important advantages. Specifically, with the right animal
it might be possible to locate the neural circuit that supports the memory and
study the synaptic connections in this circuit that are modified by experience.

Mechanisms of Synaptic Plasticity 21
In the late 1960s, Eric Kandel (1976) followed this
strategy to initiate a research program that focused on
an invertebrate named Aplysia Californica, a large sea
slug. This animal has several important properties.
• It has a behavior called the gill withdrawal
reflex that can be modified by experience.
• It has a relatively simple brain, located in its
abdomen, called the abdominal ganglion,
which has far fewer neurons than any verte-
brate brain.
• The cell bodies of these neurons are very large,
almost visible with no magnification.
• The location of individual neurons is consistent from one animal to
another.
The gill of the sea slug is the principle organ for extracting oxygen. The gill
withdrawal reflex is a defensive behavior the animal displays when its skin
is stimulated. See Figure 2.1A for an illustration of the gill in its normal state
and when a tactile stimulus is applied to its siphon. Note that the gill contracts
when the siphon is touched. This simple behavior can be modified by experi-
ence. If the siphon is tapped every few seconds, the amplitude of the response
decreases. This change in behavior is called habituation: the magnitude of the
response decreases with repeated stimulation. After the response has diminished,
if there is a significant pause between taps, the response to the next tap will
increase. This is called spontaneous recovery: with the passage of time between
stimulus presentations the response to that stimulus can recover.
The phenomenon of habituation coupled with spontaneous recovery
is referred to as short-term habituation. If the experiment is repeated over
several days, the amount of spontaneous recovery greatly diminishes. This
is called long-term habituation. The gill withdrawal reflex also can become
more responsive by strongly stimulating (shocking) the animal’s tail. Thus,
a strong stimulus to the tail greatly enhances the gill withdrawal response to
the relatively weak stimulus applied to the siphon (Figure 2.1B). This is called
sensitization.
The set of phenomena just described is not unique to sea slugs. Reflex-
ive responses elicited in other animals, including people, also habituate,
show spontaneous recovery, and can be sensitized by strong stimulation. So,
although habituation is a simple behavioral adaptation, it is quite general.
Behavioral habituation clearly meets the definition of learning and memory.
In some way, information contained in the tap persists in a form that can
influence behavior.
Eric Kandel

22 Chapter 2
Figure 2.2 illustrates the Aplysia abdominal ganglion structure and the
locations of the large cell bodies of its neurons. Remarkably, the abdominal
ganglion can be isolated from the body of the animal while still connected to
the sensory neurons that respond to the siphon taps and to the motor neurons
that, when activated, cause the gill to retract. This feature makes it possible
to identify the exact connections that participate in the gill withdrawal reflex,
that is, to map out the circuit of neurons that support the behavior. Once
the part of the neural circuit that is modified by repeated taps is discovered
Magnitude
of
gill
contraction
(B)
(A)
4 8 12
0 4 8 12
0 4 8 12
0 4 8 12
0
Time (s) Time (s) Time (s) Time (s)
Touch
siphon
Touch
siphon
Touch
siphon
Trial 1 Trial 6 Trial 13
Shock tail and
touch siphon
Trial 14
Parapodium
Siphon
Mandle shelf
(retracted)
Gill
Figure 2.1
(A) An illustration of the gill of Aplysia Californica in a relaxed state (left) and its with-
drawal when the siphon is touched (right). (B) The gill withdrawal reflex habituates.
Note that on Trial 1 a touch to the siphon produces vigorous withdrawal but that by
trial 13 the same stimulus fails to elicit a response. Sensitization is illustrated on trial
14 where a strong shock applied to the tail restores the response.

(Figure 2.3), one is then in a position to study synaptic mechanisms that allow
experience (repeated taps) to modify the gill withdrawal behavior.
Kandel and his colleagues were able to locate the site of the memory
trace—the set of synapses connecting sensory neurons from the siphon to
the motor neurons that controlled the gill withdrawal reflex. The part of the
circuit that was modified was the synapse. Repeated tapping caused changes
that weakened the strength of the synapses connecting the sensory and motor
neurons.
The story of just what happens when the gill withdrawal reflex habituates
is about discovering synaptic mechanisms that participate in this change.
Much of this has been described in Kandel’s papers, including one based
on his Nobel Prize address (2001). The goal of this discussion, however, is
only to introduce the logic behind the simple system approach. By trading
complexity for simplicity, researchers who have employed the simple system
approach have made important contributions to the understanding of how
experience modifies synapses and have provided important clues to how
memories are made.
L2 L3 R3 R4
R5
R8
R14
R7
R15
R6
R1
R2
L6
L4
L11
L91
L92
L1
LDGI
RDG
Siphon
nerve
Genital–pericardial
nerve
Left connective
tissue
Right connective
tissue
Anterior
Branchial
nerve
500 μm
Figure 2.2
The abdominal ganglion of Aplysia Californica. The cell bodies are large and identifi-
able from one animal to another.

24 Chapter 2
Long-Term Potentiation in the Hippocampus
No one would seriously imagine that the information contained in the modi-
fied sensory–motor synapses of a sea slug remotely resembles that which is
contained in the modified synapses that would let you recall where you went
to lunch yesterday and who was with you. This kind of information requires
memory traces that are far more complex and integrated. Yet, it is becoming
increasingly likely that specific circuits that contain such complex traces can
be identified in mammalian brains. However, there is good reason to believe
that a structure in the brain called the hippocampus contains modifiable syn-
apses that can maintain this kind of information (see Chapters 15 and 16).
Moreover, the anatomical organization of the hippocampus is well known.
Indeed, the hippocampus has a very interesting anatomical organization—
a so-called trisynaptic circuit—that attracted neurophysiologists who were
interested in studying neuron-to-neuron communication. This circuit is
shown in outline form in Figure 2.4. The three components of the circuit are:
1. Neurons in the entorhinal cortex connect to a region in the hippocam-
pus called the dentate gyrus by what is called the perforant path.
Interneuron
Motor
neuron
Gill
Modulatory
interneuron
Tail
Siphon
skin
Sensory
neuron
Sensory
neuron
Stimulus
shock
+ +
Figure 2.3
A diagram of the neural circuit that supports the gill withdrawal reflex and sensitiza-
tion. Stimulation of the siphon activates a sensory neuron that synapses onto an
interneuron and a motor neuron, which produces the contraction of the gill. Habitua-
tion occurs because repeated taps to the siphon weaken the synaptic connections
between the sensory and motor neurons. Note that the circuit activated by tail shock
connects to the sensory neuron. Stimulating the tail enhances the size of the gill with-
drawal reflex elicited by the siphon.

2. Neurons in the dentate gyrus connect to the CA3 region by what are
called mossy fibers.
3. Neurons in CA3 connect to neurons in the CA1 region by what are
called Schaffer collateral fibers.
Although it is not possible to study specific neuron-to-neuron connections
in the intact hippocampus, the organization of the hippocampus makes it
possible to study connections between neurons in one region or subfield with
neurons in another subfield. The specific methods are described in a later
section. The basic strategy is simple: you stimulate a set of fibers known to
synapse onto neurons in a particular subfield and record what happens in
that region when the impulse arrives. If the fibers connect to cells near the
recording electrode, you will detect a response in those neurons.
Working in Per Andersen’s laboratory, Timothy Bliss and Terje Lomo
(1973) took advantage of the anatomy of the hippocampus in a living rab-
bit to determine if it was possible to modify the strength of synapses. They
Rodent hippocampus
Entorhinal
cortex
Perforant path
Mossy fibers
Schaffer
collaterals
Dentate
gyrus
CA3 pyramidal
cells
CA1 pyramidal
cells
Mossy
fibers
Schaffer
collaterals
Perforant path
(from entorhinal
cortex)
Dentate
gyrus
CA1
pyramidal
cell
CA3
pyramidal
cell
+
+
+
Granule
cell
CA3
CA1
Figure 2.4
The hippocampus has a very interesting anatomical organization. This schematic rep-
resentation of the rodent hippocampus shows the direction of the flow of information.

26 Chapter 2
stimulated the fibers in the perforant path and recorded synaptic
activity that occurred in the dentate gyrus (Figure 2.5). Their experi-
ment was simple:
1. They established that a weak stimulus applied to the perfo-
rant path would evoke some synaptic activity in the dentate
gyrus.
2. They next delivered a stronger stimulus to the same perfo-
rant path fibers, which evoked a bigger synaptic response.
3. They then repeatedly presented the weak stimulus and
found that it now evoked a bigger response.
Timothy Bliss
Mossy
fibers
Schaffer
collaterals
Perforant path
Dentate
gyrus
CA1
pyramidal
cell
(A)
+
+
+
Granule
cell
SE
CA3
CA1
Synaptic
activity
WS SS WS
(B)
LTP
RE
CA3
pyramidal
cell
Figure 2.5
(A) Bliss and Lomo discovered LTP by stimulating (S) the per-
forant path and recording (R) in the dentate gyrus. (B) They first
applied a weak stimulus (WS) to the perforant path and mea-
sured synaptic activity. They then applied a strong stimulus to
the perforant path. It evoked more synaptic activity than the ini-
tial weak stimulus. In addition, however, the strong stimulus (SS)
produced an enduring increase in the synaptic response to the
WS. This enhanced response is called long-term potentiation
(LTP). SE = stimulating electrode; RE = recording electrode.

Thus, the strong stimulus potentiated the response
to the weak stimulus. The potentiated response
lasted a relatively long time (several hours). This
phenomenon is called long-term potentiation (LTP).
As noted, neurobiologists believe that experience is
stored in the brain because it modifies the strength
of synapses connecting networks of neurons. Thus,
Bliss and Lomo’s discovery of LTP was greeted with
great enthusiasm because it provided a way to study
how synaptic strength can be modified by experi-
ence. Hundreds of researchers have dedicated their
scientific careers to the study of LTP as a model sys-
tem for discovering the synaptic mechanisms that produce lasting changes
in synaptic strength. The work of these scientists has greatly increased our
understanding of these mechanisms and identified a number of important
molecules and processes that are likely to be involved in making memories.
To appreciate their discoveries, it is necessary to have a detailed understand-
ing of the methodology used to study LTP and its conceptual basis.
The Conceptual Basis and Methodology of LTP
Although Bliss and Lomo discovered LTP in the hippocampus of a living rab-
bit, the most widely employed basic procedure for studying LTP centers on
what is called an in vitro preparation (Figure 2.6A,B). It requires dissecting
a very thin slice of tissue from the hippocampus and placing it into a special
chamber that contains a cocktail of chemicals in a solution that will keep the
slice of tissue functional for several hours. A stimulating electrode is then
positioned to deliver electrical current to a chosen set of fibers and a recording
electrode is placed in the region where these fibers terminate.
Bliss and Lomo (1973) stimulated the fibers in the perforant path and
recorded the synaptic response in the dentate gyrus. Many researchers choose
instead to stimulate the Schaffer collateral fibers and record the response of
the pyramidal cells in the CA1 subfield (Figure 2.6C). The recording electrode
is placed in the extracellular space among a population of pyramidal cells in
CA1. It records the extracellular excitatory postsynaptic potential (EPSP) in
a particular area and is referred to as the field potential (also called the field
EPSP or fEPSP). The field potential is a critical concept because it is what is
measured in an LTP experiment.
Terje Lomo

28 Chapter 2
(A) (B)
Mossy
fibers
Schaffer
collaterals
Perforant
path
Dentate
gyrus
CA1
pyramidal
cell
CA3
pyramidal
cell
+
+
+
Granule
cell
CA3
CA1
RE
SE
(C)
Figure 2.6
LTP can be studied in tissue slices taken from the hippocampus. This is called an in
vitro preparation. (A) The recording apparatus consists of a large chamber that is filled
with fluid needed to keep the slice viable, a small chamber that holds the slice being
studied, the stimulating electrode used to induce LTP, and the recording electrode
used to measure the field EPSP. (B) Prior to beginning the experiment, slices of hip-
pocampal tissue are placed into the small recording chamber. (C) Many researchers
use the in vitro methodology to study LTP induced in neurons in the CA1 region of
the hippocampus. To do this they stimulate the Schaffer collateral fibers and record
field potentials from a recording electrode placed in the CA1 region. SE = stimulating
electrode; RE = recording electrode.

Understanding the Field EPSP
To more fully understand the fEPSP requires a review of the basic structure
and function of the neuron and how neurons communicate, as well as a dis-
cussion of membrane potential and depolarization.
STRUCTURE AND FUNCTIONS OF THE NEURON An idealized neuron is pre-
sented in Figure 2.7, which shows that a neuron is composed of a cell body,
dendrites, an axon, and axon terminals. Neurons are connected in networks
and serve many functions. A neuron is:
• an input device that receives chemical and electrical messages from
other neurons;
• an integrative device that combines messages received from multiple
inputs;
• a conductive–output device that sends information to other neurons,
muscles, and organs; and
• a representation device that stores information about past experi-
ences as changes in synaptic strength (Figure 2.8).
The function a particular neuron serves depends on whether it is a presyn-
aptic “sending” neuron or a postsynaptic “receiving” neuron. As noted in the
previous chapter, the synapse (Figure 2.8) is the point of contact between the
sending and receiving neuron. It is where neurons communicate and informa-
tion is thought to be stored. The basic components of the synapse are the pre-
synaptic terminal, the postsynaptic dendrite, and the synaptic cleft, which
is a small space between the terminal and the spine that contains structures
that maintain the connection.
Cell body
Dendrites
Nucleus
Axon
Axon
terminals
Idealized neuron
Figure 2.7
A neuron is composed of a cell body (which contains the nucleus), dendrites, an
axon, and axon terminals.

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sides; on the other, oppositely to the centre building, is Colonel Lee’s
neat and beautiful dwelling. The houses belonging to the arsenal are
built of brick externally, while internally every thing is of wood; and
as, during the winter season these buildings are heated with wood,
there appeared to me to be much danger of fire. I remarked this to
Colonel Lee, who appeared to participate in my apprehensions. After
our return to the tavern, Mr. Calhoun, with whom we had become
acquainted through Mr. Bates, introduced us to several gentlemen of
the town, and took us in the evening to a musical party at the house
of a Mr. Dwight, where we found the fashionable part of society
assembled. The ladies sang very well, and played on the piano-forte
several pieces from “Der Freischutz,” an opera which is at present a
favourite in America.
We had determined to go on the 12th of August to New Lebanon, to
visit the Springs and the Shaker’s village, but the Fates had decreed
otherwise. We left Springfield at two o’clock in the morning in the
stage, rode over the bridge, through Westfield, which, as far as we
could judge in the dark, is a handsome village, and arrived at day
break in a romantic valley, on Westfield river, whose waters fall over
huge rocks. At Russel, which is situated in an uncultivated valley,
seventeen miles from Springfield, we partook of an excellent
breakfast at the stage-office, and were much pleased at the clean
and comfortable appearance of the houses and inhabitants. It was
so cold early in the morning, that a large fire which we found at this
house, was quite comfortable. The road through the wild romantic
valley, generally ascending, and along the river, was rather bad, and
often very narrow; instead of a railing, there were only trunks of
large trees, which were permitted to decay in a very unjustifiable
manner. The bridges also were as badly built as those of which we
have already complained. The forest trees were very handsome, but
many of them are destroyed for the cabins of the new settlers.
These dwellings, like the log-houses, are built of the trunks of large
trees. Amongst the few settlers whom we observed there, were
several negro and mulatto families. The villages of Chester, Bucket,
and Lee, through which we passed, consist of but few houses; Lee,

however, appears to be a flourishing village. At this place we left the
mountains, and again entered upon a better cultivated region, in
which we observed stubbles of wheat and rye.
Exceedingly fatigued in consequence of the great heat, and the
number of passengers in the stage-coach, I was anxious to procure
a carriage in order to visit New Lebanon, distant fourteen miles; but
the person of whom I inquired was so extortionate as to ask ten
dollars. I determined, in order to avoid a new yankee trick, to
prosecute my journey in the stage-coach, direct for Albany. At
Canaan, thirteen miles distant, we left the state of Massachusetts,
and entered that of New York. The other villages which we passed
after our departure from Canaan, were Chatham, six miles, Nassau,
or Union Village, four miles, and Schoodie, five miles. The distance
from Springfield to Albany is eighty-one miles. The above villages
have a neat and comfortable appearance, and the fields were in a
good state of cultivation. Upon our arrival at Schoodie the night was
just setting in, but unfortunately we were lighted by a burning house
upon an eminence not far off. At the village of Greenbush, near
Albany, we crossed the Hudson or North river in a horse-boat, and
upon our arrival in the city took lodgings at Cruttenden’s boarding-
house, on an eminence near the capitol or state-house.
Albany contains about fifteen thousand inhabitants. It is situated
upon the right bank of the Hudson, and extends westward upon an
eminence. It was built by the Dutch in 1614, under the name of Fort
Orange, and received its present name after it came into the
possession of the English, in honour of the afterwards unfortunate
King James II. who was then duke of York and Albany. Some of the
Dutch houses are still standing, and several of the streets retain
their original names.
At the tavern we met with a Mr. Jackson, from New York, who had
arrived at the same time, and who was accompanied by his sister
and his son, Columbus, a sensible lad about ten years of age. Mr. J.
is a teacher. In consequence of the vicinity to the Ballston, Saratoga,
and New Lebanon springs, and the fashionable season, the hotel

was so full of strangers, that I was obliged to sleep with Mr. Tromp,
in a small chamber. On the following morning, at the public
breakfast, I again met with Mr. Jackson and Columbus, and as he
was acquainted in Albany, I accepted of his invitation to take a walk
through the city. It is old and in some parts appears to be in a state
of decay. During the late war with England it was in a quite
flourishing state; but since the peace it has suffered considerably, in
consequence of some heavy failures and a great fire. Albany has
received a new impulse, an increase of commerce, and expects to
reap the most happy results from the Erie Canal, which has been
lately established, and which commences here, and runs a distance
of three hundred and sixty-two miles to Lake Erie, as well as from
the canal from Lake Champlain. The pavements were so bad that I
was obliged to complain immediately upon our arrival, and this I was
subsequently forced to repeat; the streets were also very crooked.
We visited several bookstores, which appeared to be well furnished,
and then took a walk to the new basin, into which the canal empties.
It is separated from the Hudson by a dam which runs parallel with
the river, and is four thousand feet long, from three to four hundred
wide, and ten feet deep. The dam is built of strong rafters, which
form its two walls, the intervals of which are filled up with earth and
stone. It is connected with the bank of the river by several high
wooden bridges, in the centre of which there are drawbridges for the
passage of boats. The building of this dam cost one hundred and
thirty thousand dollars. It was divided into lots, and sold separately,
on condition that store-houses should be erected upon it: in
consequence of this they have realized the sum of one hundred and
ninety thousand dollars. In my opinion, the managers of the canal,
at whose expense the basin and the two canals have been built,
would have done better, if they had kept the dam and rented it.
Being built of wood, which is more or less subject to decay, as they
are to erect nothing but store-houses upon it, it is to be feared that
in the course of ten years it will tumble down in consequence of the
pressure, or that they will be obliged to repair it in great measure, or
perhaps completely rebuild it with stone. As stone is very cheap
here, and sawed in the prisons, they should have originally built the

dam of stone. The present one seems to me to have been but badly
executed. In the basin we saw a travelling bookstore in one of the
canal-boats. Mr. Wilcox, who established it about two years ago on
the Erie Canal, travels backwards and forwards several times a year,
and is said to do considerable business. He had just returned to get
a new assortment of books. Most of the books which he sells at the
villages in the neighbourhood of the canal are ancient authors, some
medical and religious, and a few law books and novels. This
gentleman, formerly a merchant in Albany, entirely supports his
family, who reside with him in his boat, by this fortunate speculation.
I purchased of him an excellent map of the state of New York.
A few hours after, we visited some of the steam-boats which ply
between Albany and New York. The largest, called the Car of
Commerce, is provided with excellent apartments, and makes her
trip in nineteen hours. This vessel is extremely elegant, but my
friend Tromp is of opinion that the English steam-boats are superior
in machinery. In fact, in this country, the American steam-engines
are not celebrated for the safety of their boilers; and several
explosions which have occurred, serve to increase this evil report.
From this reason, as well as on account of the disagreeable motion
of the steam-engine, many persons were unwilling to risk their lives,
so that they have attached a safety-barge to one of the steam-boats.
This is a real floating hotel, furnished with the greatest luxury. In the
ladies cabin there are even silk curtains. Besides this, the ladies have
a separate toilette and parlour. The gentlemen assemble in the
dining room. The whole boat is surrounded by a piazza, which, in
warm weather, must be extremely pleasant. The name of this safety-
barge which carries passengers at four dollars, is Lady Clinton, in
honour of the wife of the governor of New York, De Witt Clinton. We
also visited the Constellation, another beautiful steam-boat, which
has no safety-barge. There are also steam-boats for the purpose of
towing the common sloops, &c. up and down the river, called steam-
tow-boats.
Finally, we examined the horse ferry-boats. These boats consist of
two vessels joined together, have a common deck, and are of an

elliptical form. Upon the centre of the deck is a round house, in
which six horses work, turning a horizontal, which moves two
common wheels between the boats, provided with paddles, as in the
steam-boats. The carriage, and twenty-two two-horse carts crossed
at the same time, standing on both sides of the round house. There
are two rudders, one at the stern, the other at the bow.
The trade in timber and boards is one of the capital branches of
internal trade. We saw a great quantity of both on the wharves, and
at the dam. At dinner we became acquainted with the Spanish
consul of Boston, a worthy young man, who was educated in France.
After dinner we took a view of the capitol, or state-house, situated
upon a small eminence, and at a short distance from our inn. Albany
is the seat of government and the capitol of the state of New York,
but it is said to be the intention of the inhabitants shortly to remove
the seat of government to Utica, which is situated farther to the
west, and in a more central part of the state. The capitol is built of
brown sand-stone, and in a quadrangular form; in front it is
ornamented with large steps, and four Ionic columns of white
marble. The halls of the different branches of the legislature are
spacious, but exhibit nothing remarkable. In one of the halls is a full
length portrait of Washington, and in another, that of the late
Governor Clinton, an uncle of the present governor. I.9 On the top of
the capitol is a cupola, from which there is a beautiful view of the
city of Albany, and the valley of the Hudson, which is bounded on
the right by the Catskill mountains, and on the left by the mountains
of Vermont. On the dome is a wooden statue representing justice, to
the back of which is secured a heavy lightning-rod, so that witlings
remark that she is standing in the pillory.
At Albany are some remains of the feudal system. The Van
Rensselaer family, one of the oldest of the Dutch emigrants,
obtained the country around Albany at the time it was first settled,
as a fief; it was divided into different portions, and some of these
were leased to vassals who were obliged to pay a certain rent, and
to render certain services to the owner. The eldest of the Van
Rensselaer family has always borne the title of patroon, and enjoys

certain feudal prerogatives, for which the family are indebted to the
great popularity they have enjoyed ever since the revolution, though
every recollection of the feudal system is repugnant to the genius of
the American government. By the people in the neighbourhood, the
house of the old General Van Rensselaer is always called the manor
of the patroon.
CHAPTER VI.
Journey from Albany to the Falls of Niagara.—Erie Canal.—
Schenectady.—Utica.—Rochester.—Buffalo.—The Falls of
Niagara, from the 14th to the 25th of August, 1825.
ON the morning of the 14th of August, we took passage on board
the Albany, one of the canal packet-boats, for Lake Erie. This canal
was built at an expense of $2,500,000, and will be completed in
about four weeks: at present, they are at work only on the western
part of it. During the preceding year, they received an income of
$300,000, and they expect, during the present year, after the canal
shall have been completed, an income of $500,000, so that the
expenses will, in a very short time, be replaced, and the state realize
an immense profit, unless it be necessary to make great repairs,
which I have no doubt will be the case, and will consequently
require a large share of this income. Hitherto the great canal system
was unknown in the United States, and was rather unpopular. It
might have been expected, therefore, that so great and rapid an
undertaking, would have a tendency to astound, if we may so speak,
the public mind; so that this canal was finished as soon as possible,
without calling to aid the great experience possessed by other
nations. Notwithstanding, this canal, which is three hundred and

sixty-two miles in length, with eighty-three locks, between the
Hudson and Lake Erie, which lies six hundred and eighty-eight feet
above the level of the former river, does the greatest honour to the
genius of its projector; though one who has seen the canals in
France, Holland, and England, will readily perceive, that the water-
works of this country afford much room for improvement. The canal
is thirty-five feet wide on the surface, twenty-eight feet at the
bottom, and four feet deep, so that none but flat vessels and rafts
can sail on it. The packet-boat which took us to Schenectady, was
seventy feet long, fourteen feet wide, and drew two feet water. It
was covered, and contained a spacious cabin, with a kitchen, and
was very neatly arranged. On account of the great number of locks,
the progress of our journey was but slow: our packet-boat went only
at the rate of three miles an hour, being detained at each lock, on an
average, four minutes. The locks are fourteen feet wide above the
surface, and have a fall from seven to twelve feet. The packet-boat
was drawn by three horses, which walked upon a narrow tow-path
leading along the canal, and beneath the numerous bridges which
are thrown over it. These bridges, of which there are about three
hundred between Albany and Utica, are all built of wood, and in a
very awkward style; most of them belong to the farmers, and are
intended to serve as a means of communication between their fields.
The distance from Albany to Schenectady, by land, is only fifteen
miles, and persons are enabled to travel it in a very short time in the
stage-coach; but as we were anxious to see the canal, and get
leisure to complete our journals, we preferred going by water,
twenty-eight miles.
At Troy, five miles and a half from Albany, is the government arsenal,
which appears to be a large establishment. As far as this place, the
canal runs nearly parallel with the Hudson. Troy, which is very
pleasantly situated on the left bank of the river, at the foot of several
tolerably high mountains, one of which is called Mount Ida, appears,
if we may be permitted to judge from the large store-houses and the
good appearance of the dwellings, to be a wealthy place. Here is a
branch canal which has two locks, and establishes a communication

with Troy. Shortly after, we arrived at a place where there are no less
than nine locks, with an ascent of seventy-eight feet. In front, and to
the right of this, is another canal, which unites with the Hudson and
the canal from Lake Champlain. At this place we left the Hudson and
directed our course along the Mohawk river. During our ride we
observed a covered wooden bridge, which extends over the latter
river, a short distance from its mouth, and is about six hundred feet
in length, supported by fifteen wooden piers. Here we saw the
famous Cohoes Falls of the Mohawk river, seventy-eight feet in
height and about four hundred feet wide. In the spring, when these
falls extend over the entire bed of the Mohawk, they are said to be
extremely magnificent; during the present dry weather, they
presented a very handsome appearance, though they were very
small. The river was almost completely dried up. I walked over its
bed, which consists of slate rock, as far as its middle and near to the
falls. In some places the rocks are excavated by the action of the
water, and you may see holes which are full of water and are said to
contain excellent fish. Finding great difficulty in continuing the canal
on the right bank of the Mohawk, they were obliged here to carry it
to the opposite side by means of an aqueduct-bridge, one thousand
one hundred and eighty-eight feet in length. This bridge is of wood,
and is supported by twenty-six stone columns, on account of which,
they have placed a chevaux-de-frise, to keep off the ice in the river
about one hundred yards off. The part of this wooden canal, which
contains the water, is about twenty feet wide and has a tow-path
eight feet wide on one side. These wooden aqueducts will probably
soon require repairing, and there is no doubt but that they will
ultimately be obliged to build them of iron. The canal is cut through
the rocks, almost the whole distance, where it runs along the left
bank of the Mohawk, and presents a very handsome appearance.
Twelve miles farther on, it returns again to the right bank of the
Mohawk by a similar aqueduct, seven hundred and forty-eight feet in
length and supported by sixteen piers. Above this aqueduct, which is
also protected by a chevaux-de-frise, there is a common wooden
bridge thrown over the river, for wagons. Four miles farther on is
Schenectady, where we arrived after sunset. Between this town and

Albany, we passed no less than twenty-seven locks. These, though
they are built of solid lime-stone, will soon require repairing, as the
water passes through them in various places. The gates also lock
badly, so that the water which percolates forms artificial cascades.
The country through which we passed to-day was generally wild and
hilly, and somewhat thinly settled.
Schenectady is an old town containing about five thousand
inhabitants, and is intersected by the canal. At this place we left the
packet-boat, in order to proceed to Utica next morning in another
boat, and found excellent lodgings at Given’s hotel, which, after the
great heat we had endured during the day, was exceedingly
agreeable. Its inhabitants are, in part, descendants of the Lower
Saxons, and some of them whom I saw at the tavern conversed with
me in bad Dutch. Early on the next morning we walked through the
town, and visited Union College, which consists of two large
buildings situated a short distance from the town upon a little
eminence. It was the time of vacation, and consequently it was
perfectly silent. From its decaying appearance, I should judge the
college was not in a very prosperous condition. From this building
you have a beautiful view of the town, and of the Mohawk valley,
which appears here to be well settled. In the town we observed a
peculiar windmill, with a horizontal wheel, whose sails, about twenty
in number, stand perpendicularly.
We left Schenectady early in the morning on board the packet-boat
Samuel Young, which had engaged to take us to Utica, eighty miles
distant, by an early hour the next day. It was a large boat, and, as
the passengers are obliged to spend the night on board, is provided
with separate apartments for the ladies. The canal again ran along
the well-cultivated valley of the Mohawk, and the country, on
account of the foliage of the trees upon the heights was beautiful.
The village of Amsterdam consists of a few neat houses; and
opposite, on the right bank of the Mohawk, is Rotterdam. On our
way we passed several small aqueducts, the longest of which rest
only upon three piers, and extend over small brooks, which, as well
as the small rivulets, are distinguished by the Indian appellation of

“creek.” The canal is carried over two rivers, called Schoharie and
Canajoharie creeks, from which it receives the most of its water. At
this place the horses are conveyed to the opposite side of the two
rivers by means of ferry-boats. At the first ferry is a small village,
called Fort Hunter, where, before the revolution, there had been a
fort, or rather a redoubt of the same name. Towards evening we
passed through a valley, which is formed by two rocky mountains,
one of which is called Anthony’s Nose. The houses we saw on our
route, had generally a handsome appearance; to-day and yesterday
I observed also some saw-mills. There are twenty-six locks between
Schenectady and Utica. The day was intolerably warm, and our
company was very numerous. I confined myself to writing, the whole
day, as much as possible; but, in consequence of the heat, I could
not avoid sleeping. In the evening we fortunately had a thunder-
storm, which cooled the air. During the night, as there was a want of
births, the beds were placed upon benches, and, as I was the tallest
person, mine was put in the centre upon the longest bench, with a
chair as a supplement. It had the appearance of a hereditary
sepulchre, in the centre of which I lay as father of the family. I spent
an uncomfortable night, on account of my constrained posture, the
insects which annoyed me, and the steersman, who always played
an agreeable tune upon his bugle whenever he approached a lock.
During the night we passed an aqueduct bridge, which stands over a
solace, called Little Falls. Towards morning we passed through a
well-cultivated region, with some neat houses, called German flats,
and which was settled by some Germans during the time of Queen
Anne. At about twelve o’clock at noon we arrived at Utica, nine miles
from the place where we passed a lock, which is the last that occurs
in the next seventy miles. The land appeared to be marshy, and
consisted of sand and pebbles.
Utica, which is intersected by the canal, is a flourishing town, of
about four thousand inhabitants, and stands upon the site where
Fort Schuyler, a redoubt against the Indians, was formerly situated.
In 1794, there was a small tavern here, which was the only dwelling
house in this part of the country; but at present Utica is one of the

most flourishing towns in the state of New York, and new houses are
continually building. In fact, it is only here that a person begins to
admire the great improvements in cultivation, and gets perfectly new
ideas of the works of man, and of his enterprising genius! Utica, on
the right bank of the Mohawk, has two banks, four churches, an
academy, and large and convenient stores, a bookstore, and
printing-office. It has also several ale-houses, and three fine taverns,
at the largest of which, called Shepherd’s hotel, we found excellent
accommodations. In this house there are always more than seventy
beds for the accommodation of strangers; and these, on some
occasions, are barely sufficient. The number of travellers this
summer, is said to have been unusually great, especially from the
southern states, where the heat is intolerable, and the summers
generally unhealthy. In such an American tavern every thing is
perfectly comfortable, and proportionably cheap. The price for board
and lodging is a dollar a day. The bell for rising rings before seven
o’clock in the morning. The bed-chambers are spacious, the beds
wide and comfortable, and the linen fine and perfectly clean. The
bed-chambers, moreover, are furnished with the necessary wash-
stands, &c. After a person is dressed, he enters the bar-room, where
he finds all kinds of strong and refreshing drinks; the desk of the
head waiter is also here, who attends to the bill. The inn-keeper is
generally a gentleman, who eats with the guests, and leads the
conversation. Besides the entry, where the boots and shoes are left
in the evening, and where they are found well cleaned in the
morning, there are several sitting, reading, and writing parlours, &c.
And if a person wishes a separate sitting-room, especially when he
travels with ladies, it may be readily had at a separate charge. Half
an hour after rising, they ring the bell for breakfast; and, upon going
to the dining-room, you find upon a covered table, beef-steaks,
mutton, broiled chicken, or other fowls, fish, and boiled potatoes,
which are of a very superior quality. The waiters, or in many places,
the servant-maids, hand the coffee and tea. As the Americans, in
general, are a quiet people, such a breakfast, which is eaten in great
haste, is attended with but little noise. Dinner is generally served at
about two o’clock, and tea at seven in the evening. At tea, the table

is again furnished as at breakfast, with the addition of ragouts and
baker’s bread. Nobody is obliged to drink wine. There are usually
water and whiskey on the table, which are mixed in the summer, as
the most healthy drink. Every one must help himself as well as he
can, for the victuals are not handed about. Napkins you do not get,
and instead, you are obliged to make use of the table-cloth. With the
exception of the spoons, there is no silver on the table; the forks
have two steel prongs, and their handles, like those of the knives,
are of buck’s horn. It is an excellent rule, that no one on departing is
obliged to give money to the servants.
At Utica, seven of us for nine dollars hired a stage to visit the Falls of
Trenton, distant fourteen miles. Our passengers were partly from
New York, and partly from the state of North Carolina. We crossed
the Mohawk upon a covered wooden bridge, built in a bad and
awkward manner, on which I observed an advertisement, “that all
persons who pass this bridge on horseback or wagon faster than a
walk, shall be fined one dollar.” After this, our road gradually
ascended to a forest, which was, however, in part cleared for new
fields. The timber is so much neglected here, that they will very
probably feel the want of it in less than fifty years. At a short
distance from the falls of West Canada Creek is a new tavern, which
is situated in a lately cleared forest, and is built entirely of wood. At
this tavern we left the carriage, and went on foot through thick
woods, from which a pair of stairs conduct to the falls. A new pair of
wooden stairs of about eighty steps, built for the accommodation of
strangers, leads to the bed of the river. This consists entirely of
slate-rock, is about two hundred feet wide, and is enclosed between
high rocky banks, which are lined by beautiful and lofty firs, arbor
vitæ, the maple, the elm, and the cedar. This beautiful mass of
green, the azure sky, the large and variegated rocks, and the three
falls, produce a most happy effect. The rocks at these falls, which,
on account of the great heat, scarcely extended over half the river,
are so excavated by the water, that they have the form of a common
kettle. The upper falls, which are about ninety feet high, are the
grandest; and near them, under the shade of an arbor vitæ, an

adventurer has established a small tavern, which presents a very
picturesque appearance, and is said to yield considerable profit. The
rocks contain handsome petrifactions of shells, plants, and animals;
and we saw one specimen a foot and a half long, which resembled a
young alligator; of the smaller ones we took several specimens. At
the tavern where we had put up, we found a tolerably good dinner,
and towards evening returned to Utica. The day was fine and
pleasant. The thunder-storm of yesterday, had done some good.
I regretted that it was too late upon our return to Utica, to visit a
hydrostatic lock, designed to weigh the boats which pass on the
canal.
Having seen enough of the canal, and being anxious to see the
newly-settled country between this place and Niagara, we
determined to continue our journey on the next day in the stage-
coach. With this intention we left Utica at 4 o’clock in the morning of
the 17th of August, and the same day arrived at Auburn, distant
seventy-three miles. The stage-coaches in this country do not, as in
England, travel ten miles an hour, but usually six; as the country is
generally hilly, and the coach, when it carries the mail, stops at
every village where there is a post-office, on account of the great
number of newspapers; the letter-bag must be taken out, opened,
again locked, and then returned; the coachmen also are not very
punctual, so that travelling is not so rapid as it should be. The
villages between Utica and Auburn were New Hartford, four miles,
Manchester, five miles, Vernon, eight miles, Oneida, five miles,
Lenox, four miles, Sullivan, eight miles, Manlius, six miles,
Jamesville, five miles, Onandago Hollow, five miles, Onandago Hill,
two miles, Marcellus, eight miles, and Skeneatelass, six miles.
Between Manchester and Vernon day dawned, and we found
ourselves in a rather wild country, in the midst of a wilderness.
Oneida is an Indian settlement, and was built by the remnant of the
once mighty Oneida tribe, who, unlike their countrymen, unwilling to
fly before the white settlers to the west, are at present a wretched
people, despised and oppressed by their neighbours like a gang of
gypsies. They have been obliged to learn trades, and to labour on

farms; they have also been converted to Christianity by means of
missionaries, and of whom the principal one is a Mr. Williams,
a converted Indian, educated by the Quakers. On entering the
village we observed on a little eminence to the left, a small, neat,
frame church, where the Indians hold their service, and close by, an
open plain, surrounded by butternut trees, called “Council Grove”
where the elders of the tribe assemble to deliberate on their most
important affairs. The houses of the Indians are scattered through
the fields, are generally small, and built of logs. In the centre of the
village are white settlers, mechanics and tavern-keepers; the latter
of whom in particular make out well, as the Indians are fond of
strong drink. The land belongs to the whole tribe, and each
individual labours for the common good. We observed several
Indians along the road. They had a tawny complexion, and black
hair; the men appeared to be well built, and the women were stout,
and resemble the pictures of Esquimaux women in Parry’s Travels.
Some of them wore their hair down, which, if possible, increased
their ugliness. Both the men and women wear trowsers, generally of
blue, and ornamented with white lace; sometimes also of two
colours, like the prisoners at Boston. The men wear shirts over their
trowsers, and great-coats of cloth. The women dress in white or blue
woollen mantles. At first, I thought myself in civilized Europe, for a
great number of children came along the carriage to beg,
a circumstance which had not occurred since my arrival in the United
States. It was soon ascertained, however, that they were Indian
children, dressed somewhat like their parents, and of the same
complexion. The girls had brass buckles on their cloaks, which
fastened in front, and most of them wore large bead necklaces.
Behind this village the road led along a considerable hill, from which
we had a beautiful view of Oneida Lake, which presented the
appearance of a large stream. Here you have a number of extensive
prospects, which, however, as you see but little cultivated land and
few houses, is rather uniform. Farther on we saw a small lake called
Salt Lake, which is in the midst of a forest, and has on its banks
three picturesquely situated towns, Liverpool, Salina, and Syracuse.

At Salina are rich salt springs, the water of which is collected in
reservoirs, and it is evaporated by the heat of the sun to procure the
salt. Beyond Sullivan we passed through the village of Chitteningo. It
contains several mills, a cotton factory, and a branch of the Erie
Canal, which forms a kind of harbour, and serves as a landing place
for articles manufactured here, and for the plaster and lime which
are procured in the neighbourhood. This lime becomes hard under
water, so that it is excellently adapted to waterworks. We dined at
Manlius, a new village, containing two churches. Besides the usual
stage-coach there were two others to-day, all full of passengers. In
our own we had for a short distance a farmer, a descendant of a
German emigrant, who spoke the language that was used in
Germany about a hundred years ago. He thought my German was
too high, and that I spoke it like a parson. From the canal which
forms an angle here, we drove in a southerly direction, in order to
keep on the plains, as the main road, which is nearer, leads over a
hill. The two Onondago villages appear to be flourishing
manufacturing places, and are pleasantly situated. Marcellus is also
a new village and has two churches. Most of the small villages have
two churches, an Episcopal and a Presbyterian. In each of them, and
even at the Indian village, there is a school. In several of the villages
also I had the pleasure of seeing bookstores. Beyond Marcellus the
night unfortunately closed in, which prevented me from seeing
Skeneatelass Lake, as well as the town of the same name, which is
said to be extremely pleasantly situated on one of its banks. About
nine o’clock in the evening we arrived at Auburn, and found good
accommodations at one of the public houses. This town contains
upwards of one hundred and fifty houses, a court-house and
penitentiary, which is said to be managed in a very excellent manner.
To my regret I saw none of them; for at four o’clock the next
morning, 18th of August, we set out in the stage-coach for
Rochester, distant sixty-nine miles. The villages which we passed on
our route were, Cayuga, nine miles, Seneca Falls, three miles,
Waterloo, five miles, Geneva, six miles, Canandaigua, sixteen miles,
Mendon, fifteen miles, Pittsford, seven miles, from which latter it
was yet eight miles to Rochester.

It was just daylight as we arrived in the vicinity of Cayuga, on the
lake of the same name, which is about twenty miles long, and from
one to three wide. This lake empties into the Seneca river, which
afterwards unites with the Mohawk. We crossed the lake not far
from its mouth, on a wooden bridge, one mile in length, eighteen
yards wide, and built in a very rough and careless manner: the
planks are loose and the chevaux-de-frise is in a bad condition. On
the opposite side of the lake is a large toll-house. At a short distance
from this we arrived at Seneca Falls, so called in consequence of the
little falls of the Seneca river, which are close by, and are chiefly
formed by a mill-dam. At the tavern we met an Indian and his wife,
of the Oneida tribe, who were going on a visit to the Senecas. We
conversed with the man, who had been at school, and understood
English. He told us that he had been raised by a Quaker missionary,
and that he was a farmer, and concluded by asking for a little
money, which he probably spent with his ugly wife at the next grog-
shop.
All the villages through which we passed are quite new, and in many
places we passed through primitive forests, which, in some places,
they are just beginning to clear. At Waterloo the first house was
erected in 1816, and at present it has two churches and about three
thousand inhabitants. Several of the houses are built of brick, and
contain well furnished stores. At the tavern we saw a large, beautiful
young eagle, which had been caught in his nest and tamed. The
country beyond Waterloo was boggy, and the road in some places
made of large logs, so that we were very disagreeably jolted.
Geneva is situated at the north point of Seneca Lake, which is
between fifty and sixty miles long and about five wide. The town
derives its name from its similarity of situation to Geneva in
Switzerland. It is also quite new, and contains about four thousand
inhabitants. It has two churches and several large stone and brick
houses, of which the Franklin Hotel, situated on the bank of the
lake, is the most spacious and beautiful. I went into a bookstore to
ascertain what kind of books were most sold in this part of the
country, and was told that the ancient classics and religious books

found the most ready sale; sometimes also novels, law and medical
works. The college is said to have several hundred students. In front
of the town along the lake, there are beautiful country seats and
gardens. On the other side of the town the woods are but a short
distance from the houses, and are as yet not much cleared. We saw,
however, several tracts of timber on fire; the trees are burnt in order
to clear the land.
Canandaigua, which lies on the north point of the lake of the same
name, which is about twenty miles long, is an extremely beautiful
and pleasant town, that has been but lately settled. The Duke de la
Rochefoucault says, that during his travels in America, in 1790, there
was but a single house on this lake, in which he spent the night, in a
garret used as a store-room. Now it is a beautiful commercial town,
having one bank, a court-house, and a very superior tavern. The
court was sitting, and there was a large collection of people, so that
the town exhibited a very lively appearance. At this place the road
separates, the left goes through Batavia and several small villages to
Buffalo on Lake Erie; the right, to Rochester, and thence to Lake
Ontario and the Falls of Niagara: and as this road again approaches
the Erie canal, it is said to be the most interesting. On this account
we gave it the preference, although the longest route.
We left Canandaigua in the afternoon, and rode through Victor,
Mendon, and Pittsford, to Rochester. On this route we observed
nothing particularly interesting, excepting several new settlements;
the inhabitants of which resided in log-houses, which had a peculiar,
but by no means an unpleasant aspect. I was particularly pleased
with the neat and decent appearance of the inhabitants.
We arrived at Rochester at half past eight o’clock in the evening, and
took lodgings at the Eagle Tavern. We crossed the Genesee river,
which divides Rochester into two parts, on a wooden bridge, the first
that we had hitherto met in the United States that was built firmly
and properly. It rests upon stone piers, and is made of solid beams,
with thick and well fastened planks. The next morning we walked
through the town, and were pleased with its rapid increase. In 1812,

there was not a single house here; nothing but a wilderness; and the
land could be purchased at one dollar and twenty-five cents per
acre. At present, Rochester is one of the most flourishing towns in
the state of New York. It contains four churches, one bank, a court-
house, and about four thousand inhabitants. Many of the houses are
built of blue limestone, and of brick. The town contains several mills
and manufactories; and amongst others, a nail factory, in which the
nails are made with a machine, as in Birmingham. They also
manufacture rifle-guns, which are very long and heavy. On the right
bank of the Genesee river, the houses are not so numerous as on
the left, and there are yet many frame, and even some log-houses:
in the place where, probably in a short time, handsome wharves will
be built, there may yet be seen stumps of trees—a truly interesting
sight to those who observe the progress of this country. The
basements of the houses are generally built of rough sand-stone;
their corners, doors, and windows, of a kind of white marble-like
sand-stone, and the rest of brick. The white sand-stone is procured
in the neighbourhood, and is cut into slabs at a saw-mill on the
Genesee river. I saw three of these blocks sawed; and in one frame I
observed no less than five saws. Several hundred yards below the
bridge the Genesee river is about two hundred yards wide, and has
a fall of ninety-five feet, which at present, however, did not appear
to much advantage. Above the falls is a race which conducts the
water to several mills, and it again flows into the river below the
falls, where it forms three beautiful cascades, which reminded me of
the Villa di Mäcen, at Tivoli.
At Rochester the Erie canal is carried over the Genesee river by a
stone aqueduct bridge, and resembles that of the Bridgewater canal
at Manchester, in England. This aqueduct, which is about one
thousand yards above the falls, rests upon a base of slate rock, and
is seven hundred and eighty feet long. A work which has been lately
published, called the “Northern Tour,” gives the following description
of it: “The aqueduct consists of eleven broad arches, built in the
form of circular segments, the tops of which are raised eleven feet
above the level of the arches, and fifteen feet above that of the

water in the river. The two exterior arches have an extent of forty
feet each, and beneath them are the streams which turn the mills;
the other nine each fifty feet wide, &c.” Upon one of its sides is a
tow-path secured by iron railings. The whole is a solid work, and
does much credit to its architect, Benjamin Wright.
We left Rochester at nine o’clock, on board the canal packet-boat
Ohio, Captain Storch. The canal, between Lockport and Rochester,
runs a distance of sixty-three miles, through a tolerably level
country, and north of the Rochester ridge. This ridge consists of a
series of rocks, which form the chain of the mountains which
commences north of Lake Erie, stretches eastward to the Niagara
river, confines it, and forms its falls, then continues its course, and
forms the different falls which are north of Lake Ontario, and is at
length lost in the neighbourhood of the Hudson. It has only been
within the last year that this part of the canal has been passable; its
course is through dense sombre forests, in which are but few
settlements, such as Spencer’s Basin, Bates, and Brickport. The
bridges are better and higher than those we have mentioned in the
preceding pages. Amongst our passengers, was a Mr. Bosch, a Dutch
clergyman from Curaçao, and the Rev. Messrs. Sluiter and Wykoff,
from New York. These gentlemen, being of Dutch descent, the
conversation was generally carried on in their native tongue. Captain
Storch also, who is a native of Amsterdam, and a Jew by birth, who
has travelled extensively, made the time pass very pleasantly, by his
lively disposition, and his agreeable conversation. Both before and
after dinner, as well as at tea, the two clergymen from New York,
asked a blessing; and before we retired to bed, one of them read
several chapters in the Bible, and then made a long prayer.
We reached Lockport on the 20th of August, about 7 o’clock in the
morning. At this place the canal is carried over the ridge by five
large locks, through which the water is raised to the height of
seventy-six feet. The locks are ten in number, being arranged in two
parallel rows, so that while the boats ascend in one row, they may
descend at the same time in the other. Through this arrangement
the navigation is greatly facilitated, and the whole work, hewn

through and surrounded by large rocks, presents an imposing
aspect.
Lockport, to which we repaired, while the boat was left in the basin
at the foot of the locks, is an extremely interesting place, and is
situated just above the locks. In May, 1821, it consisted of two log-
houses; at present it contains not less than six hundred, some of
which are stone houses: it contains a post-office, one printing-office,
which issues a weekly paper, and two churches. Though at present
Lockport appears perfectly wild, yet this appearance will no doubt
vanish in the course of four or five years, so that it will present as
splendid an appearance as Canandaigua and Rochester. On our
arrival, the canal was still unfinished for about five miles; but it was
supposed that the whole would be completed before the close of the
year. They were obliged to cut it through solid rock, generally about
thirty feet deep, for a distance of more than three miles. This was
mostly effected by blasting. Several hundred Irishmen were at work.
They reside in log huts, built along the canal. They make much
money; but they suffer also severely in consequence of the
unhealthy climate, especially from fevers, which not unfrequently
prove fatal. The stone, which is quarried, is employed in building
houses, and in making turnpikes. In breaking the rocks they often
find beautiful petrifactions, and other remarkable minerals; for
example, strontian, and beautiful transparent gypsum. I saw a large
petrified tree, and a handsome petrified sea-coral.
At Lockport we took a dearborn for Buffalo, where we were anxious
to go, in order to see the union of the canal with Lake Erie. Though
a good stage runs between Lockport and the Falls of Niagara, we
went in this bad vehicle five miles, to the navigable part of the canal.
The road led through the forest, the trees of which had been felled
along the canal, and passed over the stumps, so that it was
uncommonly rough, especially as it had rained the day before.
Arrived at length at the navigable part of the canal, we took passage
on board a rather bad boat, where nothing was to be had but the
common cordial, whiskey. The village where we went on board, is
called Cottensburgh, and is quite a new settlement. At this place also

the canal is cut through rocks to the depth of about thirty feet.
About two or three miles farther on, it terminates in the Tonnawanta
Creek, which serves as a canal for twelve miles. This creek has
scarcely any outlet, so that when it rises much, they are obliged to
protect the canal by means of safety-locks near its union with the
creek. At the outlet of the creek into the Niagara is a sluice for the
purpose of keeping the water always at a certain height. The creek
itself is about fifty yards wide, and runs through a dense and
beautiful forest, which has never been touched by the axe, except
along the canal, where they have been obliged to make a tow-path.
I sat in the bow of the boat during the whole passage. Nothing
interrupted the solemn silence, except the chattering of the
boatmen’s teeth, who are often severely affected in this unhealthy
part of the country, with the intermittent fever. Another small river,
called Eleven-mile Creek, unites with the main river, and not far from
this junction was the site for the new town of Tonnawanta. A few
small houses and a saw-mill were already erected; the inhabitants
appeared also to suffer much from the intermittent fever. Here the
Tonnawanta Creek, unites with the Niagara, where the sluice which
we have just mentioned leads off. At this place also we had the first
view of the Niagara river, which conveys the waters of Lake Erie into
Lake Ontario, from the other extremity of which flows the St.
Lawrence. In the river we observed Grand Island, which contains
about one thousand one hundred acres, is overgrown with timber,
and belongs to a New York editor, Moses Mordecai Noah, a Jew, who
purchased it for the purpose of establishing a Jewish colony. The soil
is very good; during the late war between England and the United
States, the Niagara, it is well known, formed the boundary line
between them and the British provinces of Upper Canada, and this
island bore testimony of the bloody conflict. From this place, the
canal runs along the bank of the Niagara, from which it is separated
only by a small bank, built rather carelessly, and several feet above
the level of the river, which is already somewhat rapid on account of
its vicinity to the falls. On the Tonnawanta Creek we saw several
canoes which were made by excavating the trunks of trees. From
Tonnawanta to Buffalo it is eight miles, five of which we travelled on

the canal as far as Black Rock. A basin is formed here by means of a
dam situated near Squaw Island, on which is a lock communicating
with the Niagara. The whole of this work is of wood, and cannot
therefore be expected to be very durable. In the basin lay the new
steam-boat Henry Clay, of three hundred tons, intended for running
on Lake Erie. We had here the first view of the lake, whose shore
appeared to be overgrown with wood. The other shore of course we
could not see, and it seemed therefore as though we were looking
into an expanded sea. The canal to Buffalo not being completed, we
again took stage at Black Rock, and rode three miles to the former
town, where we arrived at about 5 o’clock at evening, and took
lodgings at the Mansion House, pleasantly situated on a little
eminence in the lake.
Buffalo was burnt during the late war, by the British, but it has arisen
from its ashes with increased beauty. The town contains about five
thousand inhabitants, and will, in consequence of its situation near
the mouth of the canal and its harbour, at which they are hard at
work, soon become an important place. At the entrance of the
harbour is a light-house, and on the lake we observed several
schooners of about three hundred tons. A steam-boat, called the
Superior, was ready to start with fifty passengers to Erie, and thence
to Detroit. In the streets, we saw some tolerably well-dressed
Indians of the Seneca tribe, who have their wigwam three miles
distant. Amongst them were several women, who indeed, but for
their complexion, might have been considered handsome. We also
had an amusing military spectacle. It consisted of a militia parade,
consisting of thirty men, including seven officers and two cornets.
They were formed, like a battalion, into six divisions, and performed
a number of manœuvres. The members were not all provided with
muskets, but had ramrods instead. Only the officers and the rifle-
company, four men strong, were in uniform. The band consisted of
sixteen men, and was commanded by an officer with a colonel’s
epaulets and drawn sword!
On the following day, 21st of August, we left Buffalo for the small
village of Manchester, twenty-three miles distant, and situated on

the right bank of the Niagara, near the falls. As far as the village of
Tonnawanta the road passed along the canal. It was in a very bad
condition, cut through the forest, and no pains have been taken to
remove the trees, which are thrown on the road side, and the most
beautiful trunks are permitted to spoil in a pitiable manner. On the
left we had a view of the river and of Grand-Island, thickly studded
with timber. The river is more than one mile wide below the island.
On the Canada side is the village of Chippewa. From this place,
a distance of three miles, we could already see the rising vapours of
the falls. The water, however, indicated no signs of the approach to
the precipice. It is only a short distance from Manchester, where you
perceive the lofty trees on Goat-Island with its heights, situated in
the midst of the falls, that the river becomes rocky, and the rapids
commence; these form a number of small falls, which are nearly a
mile long and the same in breadth, running as far as where the two
great falls are separated by Goat-Island.
At Manchester, we took lodgings at the Eagle Tavern, and hastened
immediately to the Falls: our steps were guided by their mighty
roaring. In a few moments we stood near the precipice, and saw
before us the immense mass of water which rushes with a
tremendous noise into the frightful abyss below. It is impossible to
describe the scene, and the pen is too feeble to delineate the
simultaneous feelings of insignificance and grandeur which agitate
the human breast at the sight of this stupendous work of nature! We
can only gaze, admire, and adore. The rocks on both sides are
perpendicular, but there is a wooden staircase which leads to the
bed of the river. We descended, but in consequence of the drizzly
rain which is produced by the foam of the water, we had by no
means so fine a prospect from below as we anticipated. On this
account, therefore, we soon ascended and satisfied ourselves by
looking from above upon this sublime and majestic sight. As we
returned, full of these mighty impressions, to the Eagle Tavern we
found to our great joy a fine opportunity of speaking of the grandeur
and magnificence we had just beheld. Lieutenants De Goer and Van

Vloten, of the Pallas, had just arrived to render homage to this great
natural curiosity.
In company with these gentlemen we took a walk to Goat-Island, by
a convenient wooden bridge, thrown over the rapids about seven
years since. The first bridge leads to a small island called Bath-
Island, which contains a bath-house and billiard-room: the second to
Goat-Island, which is about one mile in circumference, and
overgrown with old and beautiful trees. The Indians who formerly
resided in this part of the country, considered the island as sacred.
They used to say that the Great Manito or Great Spirit inhabited it.
And in fact, how could the Great Spirit manifest himself more
irresistibly than in the destructive might of the tremendous Falls?
On Bath-Island a person may approach so near to the American falls
as to look into the abyss below. The animals in the neighbourhood
are so careless of this, that the cows and horses go into the river to
drink within five yards of the brink of the precipice. From the foot of
the falls you can see nothing of the abyss, inasmuch as every thing
is concealed by the foam and vapour. On Goat-Island a person may
in the same manner approach the Canadian falls, in the centre of
which is a semicircular hollow, called the Horse-shoe, and here the
noise is still more tremendous than on the other side. The vapour
which rises from the Horse-shoe forms a thick mist, which may be
seen at a great distance. To look into the Horse-shoe is awful and
horrible. Nor can this be done but at the instant when the vapour is
somewhat dissipated. You stand like a petrified being. The level of
Lake Erie is said to be five hundred and sixty-four feet above that of
the sea, and three hundred and thirty-four feet above the waters of
Lake Ontario. Lake Ontario is consequently two hundred and thirty
feet above the level of the sea. From Lake Erie to the rapids the
water has a fall of fifteen feet, in the rapids fifty-seven feet, and
according to a recent measurement, the falls on the American side
are one hundred and sixty-two feet high. From this place to
Lewistown the river has a fall of one hundred and four feet, and
thence to Lake Ontario, of two feet.

The next morning, 22d of August, we made another visit to Goat-
Island. We afterwards descended the stairs to the river, which we
crossed in a small boat, at a short distance from both falls. The bed
of the river is said to be here two hundred and forty-six feet deep.
The current passes beneath the surface of the water, and does not
again become visible till after a distance of three miles. On the
Canada side you have a much better view of the falls than on the
American, for you see both falls at the same time. There is on the
Canada side a covered wooden staircase, which we ascended, and
approached the falls, amidst a constant drizzling caused by the
falling water. The sun threw his rays upon the thick mist and formed
a beautiful rainbow. Another winding staircase leads down the rocks
near the falls, under which you may walk to the distance of one
hundred and twenty feet; several of the gentlemen present went in,
but according to their report they could not see any thing. I was
contented therefore to behold the falls from Table rock, which almost
overhangs them. A part of this rock gave way several years ago and
fell down the precipice, and the remaining part is so much
undermined by the water that it will probably soon follow. The whole
distance from the American to the British shore is fourteen hundred
yards, of which three hundred and eighty belong to the American
falls, three hundred and thirty to Goat-Island, and seven hundred
yards to the Canada or Horse-shoe falls. On the British side, opposite
to the falls are two taverns, in the larger of which, Forsyth’s Hotel,
we took lodgings until the next day, when we intended to pay a visit
to the governor of Upper Canada, Sir Peregrine Maitland, who
resides at his country seat within a few miles of the falls. During the
late war a bridge was thrown over the river about one mile above
this tavern, which, together with a mill, was burnt by the Americans
on their retreat from the battle of Lundy’s Lane. A few years ago a
burning spring was discovered here, several of which are said to
occur in different parts of the United States. It is surrounded by a
cask, and contains a cold water of a blackish, slimy appearance, and
of a sulphurous taste. Within this cask is a small vessel which is
open at the bottom, and has a pipe at its upper end. If a lighted
candle be held within a foot of the mouth of this pipe, it will instantly

produce a strong flame, similar to a gas-light. If the vessel be taken
out, and the candle be held over the surface of the water, it will
produce the same effect, but the flame will soon disappear. In the
neighbourhood of Forsyth’s Hotel is the only point from which you
have a full view of both falls at the same time, which, however, is
often interrupted by the ascending vapour.
On our return to the American shore, we examined a camera
obscura which is situated at the head of the American staircase, and
was built by a Swiss. This gives a tolerably good view of the falls.
Afterwards we took a ride to the Whirlpool, which is three miles
down the Niagara, and is formed by a kind of rocky basin where the
river runs between narrow rocky banks. It is singular to see this
confusion of the water, whose appearance cannot be better
described than by comparing it with the flowing of melted lead. The
lofty rocks which form the banks of this river, are beautifully covered
with wood and present a stately, majestic appearance. In the
evening I again went to Goat-Island in order to view the falls by
bright moonlight: in this light they produce a very peculiarly
beautiful effect, which is greatly heightened by a moon-rainbow.
The following day, 23d August, all our company departed; my friend
Tromp and myself alone remained. We went to the other side of the
river, and took lodgings at Forsyth’s Hotel, where we found Sir
Michael and Lady Clare, from Jamaica, where Sir Michael is a
member of parliament: he was making a tour of pleasure, with his
lady, through the United States. I also became acquainted with a Mr.
Grymes, of Virginia, who was formerly attorney general of the state
of Louisiana, and is married to the widow of the late Governor
Claiborne, a beautiful and wealthy creole. As this family were also
going on a tour to Canada, I hoped to travel with them. Mrs. Grymes
spoke French, a circumstance which was exceedingly agreeable on
account of the facility with which I could converse with her. I also
found the son and adjutant of the governor, Sir Peregrine Maitland,
who had been sent by his father, to await my arrival. In a short time
after, this worthy general came himself to pay me a visit, and offer
me a room in his cottage, four miles off. This I refused, but on the

evening of the following day, I rode to Sir Peregrine’s in company
with Sir Michael and Lady Clare. The road went over the battle-
ground at Lundy’s Lane, (25th July, 1814,) which is situated upon a
gentle eminence, and through the beautiful village of Stamford. The
fields here are much better cultivated than in the United States, and
there is not so much waste of timber. The clearing is done with
much more order and regularity. Sir Peregrine resides at his cottage,
in summer, which was built by his father-in-law, the Duke of
Richmond, and surrounded by a park. His winter residence is at
York, on the northern shore of Lake Ontario, the seat of the
parliament of Upper Canada.
CHAPTER VII.
Journey from the Falls of Niagara to Montreal.—The Battle-
ground at Queenstown.—Newark.—Kingston.—Montreal.
ON Thursday, the 25th of August, we took our final leave of the falls,
in the forenoon, in company with the Grymes and Clare families, for
the town of Newark, which is situated at the junction of the Niagara
with Lake Ontario, on the Canada shore, about fourteen miles
distant. At first our road passed over small hills, until we reached the
battle-ground at Queenstown, a steep hill, which is situated behind
Queenstown, and commands a view of the whole surrounding
country. From this, the country as far as Lake Ontario, is more level.
Opposite to Queenstown, on the American shore, is Lewistown.
The battle of Queenstown took place on the 13th of October, 1812.
The English, under the command of General Brock, occupied the
heights, whose right wing borders on the Niagara, having a deep

ravine in front, and whose left wing gradually slopes towards other
no less considerable eminences, which they had slightly fortified.
General Solomon Van Rensselaer, the present post-master in Albany,
and cousin of General Van Rensselaer, the patroon, encamped with
the American troops, consisting of regulars and militia, on the
opposite shore, near Lewistown. General Van Rensselaer was
apprised that General Brock, with the greatest part of his corps, had
marched towards the west, and that there were but few troops left
on the heights. He determined therefore to cross the river, to make
himself master of so important a position. During the night he
conveyed his regulars, about one thousand four hundred men, over
the river, and gave orders that the militia should follow on the return
of the boats, and form a reserve in the rear. These troops gained the
heights, and nearly surprised the British, who, notwithstanding,
made a bold resistance. The Americans would, however, have
remained masters of the field, had not General Brock returned with
his detachment. Brock was a brave soldier, and hearing that the
troops whom he had left behind, were in a dangerous position, he
immediately attacked the Americans with but a single company. In
this attack he found a glorious and memorable death. The Americans
kept the heights as long as possible; their ammunition, however,
being nearly exhausted, General Van Rensselaer sent orders to the
militia to advance. The general himself hastened to the opposite
shore to accelerate their movements; he was answered that they
were ready to defend the borders of the United States, but it was
contrary to the laws of the country to take them out of it. The troops
of the line in the meanwhile, having exhausted their ammunition,
were obliged to retreat; they expected to embark, but not finding
any boats, they were compelled, after a heroic defence to surrender
as prisoners of war. On the place where General Brock fell, the
parliament of Canada has erected a monument to the memory of
that brave and intrepid soldier. It consists of a lofty column, which
may be observed from every part of the adjacent country. It was not
yet completed, and wanted the inscription.

We expected to meet the steam-boat Queenstown at Newark, in
order to proceed to Kingston, on the eastern extremity of Lake
Ontario. We missed it, however, and were afterwards informed that
it had been obliged to put in at another harbour on account of
repairs. We were compelled, therefore, to remain three days at
Newark. Newark is a regularly built town, with several handsome
houses; it is situated at the outlet of the Niagara into Lake Ontario,
between Fort George and Missagua. Fort Missagua is near the lake;
Fort George lies south of Newark, and is in ruins. During the last
war, both these forts were occupied by the Americans, and from Fort
George towards the town, they had raised a bulwark so as to form a
kind of intrenchment. After they had evacuated this position, and
were obliged to retreat to the right shore of the Niagara, the
commander, General M‘Clure, burnt the town of Newark, an act for
which he has been severely censured by his country. Since this
occurred, the village has never properly recovered, and its future
increase will also be slow, especially as government is digging a
canal to the west of Newark, which is to connect Lake Erie, and Lake
Ontario, which will probably hereafter withdraw all the transitory
commerce. Our time passed very agreeably in this town, particularly
through the attention of the worthy Sir Peregrine Maitland, who had
come hither; the politeness of Major Cob, and the gallant officers of
the seventy-sixth regiment, of which four companies were at
Newark, as well as the delightful singing of Mrs. Grymes, who
remained with her husband, while many others, with whom we had
expected to sail, went away.
We visited Fort Niagara, which is situated on the American shore,
and which, in consequence of its white houses, and its waving flag,
presents a very handsome appearance. The fort lies on a neck of
land; it was erected by the French in the middle of the last century,
and was shortly after taken by the British. After the peace of
Versailles in 1783, it fell into the possession of the United States,
was retaken during the late war by the British, and at the peace of
Ghent, was again obtained by the United States. We saw all that was
to be seen, and found every thing clean and comfortable. I will only

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