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i
Object-Oriented
Design Knowledge:
Principles, Heuristics and
Best Practices
JavierGarzás
Oficina de Cooperación Universitaria (OCU)S.A., Spain
Mario Piattini
University of Castilla - La Mancha,Spain
Hershey • London • Melbourne • Singapore
IDEA GROUP PUBLISHING

ii
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LibraryofCongressCataloging-in-Publication Data
LibraryofCongressCataloging-in-PublicationData
Object-orienteddesignknowledge:principles,heuristics,andbestpractices/JavierGarzasandMarioPiattini,
editors.
p. cm.
Summary:"Thesoftwareengineeringcommunityhasadvancedgreatlyinrecentyearsandwecurrentlyhave
numerousdefineditemsofknowledge,suchasstandards,methodologies,methods,metrics,techniques,languages,
patterns, knowledge related to processes, concepts, etc.The main objective of this book is to give a unified and
globalvisionaboutMicro-ArchitecturalDesignKnowledge,analyzingthemaintechniques,experiencesand
methods"--Providedbypublisher.
ISBN 1-59140-896-2 (hardcover) -- ISBN 1-59140-897-0 (softcover) -- ISBN 1-59140-898-9 (ebook)
1. Object-oriented methods (Computer science) 2. Object-oriented programming (Computer science) I. Garzas,
Javier, 1975- II. Piattini, Mario, 1966-
QA76.9.O35.O244 2006
005.1'17--dc22
2006010089
British Cataloguing in Publication Data
A Cataloguing in Publication record for this book is available from the British Library.
All work contributed to this book is new, previously-unpublished material. The views expressed in this book are
those of the authors, but not necessarily of the publisher.

iii
Object-Oriented
Design Knowledge:
Principles, Heuristics
and Best Practices
Table of Contents
Preface .............................................................................................................vi
Chapter I
The Object-Oriented Design Knowledge................................................... 1
Javier Garzás, Oficina de Cooperación Universitaria (OCU) S.A.,
Spain
Mario Piattini, University of Castilla - La Mancha, Spain
Chapter II
The Object-Oriented Design Knowledge Ontology ................................. 8
Spain
Chapter III
Using Linguistic Patterns to Model Interactions ....................................23
Isabel Díaz, Central University of Venezuela, Venezuela
Oscar Pastor, Technical University of Valencia, Spain
Lidia Moreno, Technical University of Valencia, Spain
Alfredo Matteo, Central University of Venezuela, Venezuela

iv
Chapter IV
A Framework Based on Design Patterns: Implementing UML
Association, Aggregation and Composition Relationships in
the Context of Model-Driven Code Generation .....................................56
Manoli Albert, Universidad Politécnica de Valencia, Spain
Marta Ruiz, Universidad Politécnica de Valencia, Spain
Javier Muñoz, Universidad Politécnica de Valencia, Spain
Vincente Pelechano, Universidad Politécnica de Valencia,
Spain
Chapter V
Design Patterns as Laws of Quality ........................................................ 105
Yann-Gaël Guéhéneuc, University of Montreal, Canada
Jean-Yves Guyomarc’h, University of Montreal, Canada
Khashayar Khosravi, University of Montreal, Canada
Houari Sahraoui, University of Montreal, Canada
Chapter VI
Automatic Verification of OOD Pattern Applications .......................... 143
Andrés Flores, University of Comahue, Argentina
Alejandra Cechich, University of Comahue, Argentina
Rodrigo Ruiz, University of Comahue, Argentina
Chapter VII
From Bad Smells to Refactoring: Metrics Smoothing the Way ......... 193
Yania Crespo, Universidad de Valladolid, Spain
Carlos López, Universidad de Burgos, Spain
María Esperanza Manso Martínez, Universidad de Valladolid,
Spain
Raúl Marticorena, Universidad de Burgos, Spain
Chapter VIII
Heuristics and Metrics for OO Refactoring: A Consolidation and
Appraisal of Current Issues ..................................................................... 250
Steve Counsell, Brunel University, UK
Youssef Hassoun, University of London, UK
Deepak Advani, University of London, UK
Chapter IX
A Survey of Object-Oriented Design Quality Improvement .............. 282
Juan José Olmedilla, Almira Lab, Spain

v
Chapter X
A Catalog of Design Rules for OO Micro-Architecture ..................... 307
Spain
About the Authors ..................................................................................... 349
Index ............................................................................................................ 356

vi
Preface
In order to establish itself as a branch of engineering, a profession must under-
stand its accumulated knowledge. In addition, software engineering as a branch
of engineering must take several basic steps in order to become an established
profession, highlighting understanding of the nature of its knowledge.
Software engineering experts always have used proven ideas. Concretely, in
the object-oriented (OO) design knowledge field, the practical experience of it
has been crucial to software engineers, and it is in the last years when these
ideas, materialized in items such as patterns or refactorings have reached their
biggest popularity and diffusion. And in this regard, the software engineering
community has advanced greatly and we currently have numerous and defined
chunks of knowledge, including standards, methodologies, methods, metrics,
techniques, languages, patterns, knowledge related to processes, concepts, and
so forth. Although these different areas of knowledge relate to the construction
of an OO system, there is a lot of work still to be done in order to systematize
and offer this knowledge to designers in such a way that it can be easily used in
practical cases.
A software architecture is a description of the subsystems and components of
a software system and relationships between then.1
Usually, the software ar-
chitecture is subdivided into macro and micro architecture. Whereas macro
architecture describes the metamodel of design, this that provides the high-
level organization, the micro architecture describes details of a design at a lower
level.

vii
OO design is a software design technique, which is expressed in terms of ob-
jects and relationships between those; at the level of micro architecture it in-
cludes elements such as classes, its relationships, responsibilities, refactorings,
and so on.
OO micro architectural knowledge is built upon design experiences, such as
problem solving, or lessons learned. Therefore, the OO micro architectural de-
sign knowledge has grown with time and the increasing complexity of soft-
ware. This knowledge expands and accumulates when it is stored in books and
other media for the use of designers.
In addition, the major part of OO design knowledge is difficult to identify and
use. The experience has demonstrated that design often omits common prin-
ciples, heuristics, and so on, with a consequent major loss of experience. Con-
sequently, actually, serious difficulties are still encountered when we tackle the
construction of OO systems. Although designers have accumulated a body of
knowledge that they apply during these processes, this is very implicit. Fortu-
nately, it is now being specified and popularized in different forms: principles,
heuristics, patterns, and more recently, refactoring techniques. However, today,
the difference between these concepts is generally unclear and not all of them
have received the same amount of attention or have reached the same degree
of maturity. In addition, a strong knowledge does not exist on items such as
design principles, best practices, or heuristics. The problem confronting the
designer is how to articulate all this explicit knowledge and to apply it in an
orderly and efficient way in the OODA, in such a way that it is really of use to
him or her. In fact, in practice, even such advanced subjects like OO patterns
have this problem
Design knowledge and best practices are stored in individual expert minds, or
implicitly encoded and documented in local organisational processes. It has
always been true that a significant part of design knowledge resides in the
minds of the experts that make it up. However, communities and companies are
beginning to find that it is easy to lose a vital element of their intellectual prop-
erty: corporate design knowledge. Therefore, we can say that the major part of
the design knowledge today is tacit knowledge: it in the form of project experi-
ences, heuristics, or human competencies that are difficult to be captured and
externalised.
The effective management of this knowledge is today a significant challenge.
For knowledge management to be effective, this knowledge should be orga-
nized and classified. In addition, with this purpose, developing unified cata-
logues of knowledge, ontologies, empirical studies, and so on, books and studies
such as those we present here, are very important issues to improve the use of
OO design knowledge.
Therefore, in this context, we present this book whose main objective is to give
a global vision of micro-architectural design knowledge, exposing the main tech-
niques and methods, and analyzing several aspects related to it.

viii
The subject matter in this book is divided into ten chapters. The chapters seek
to provide a critical survey of the fundamental themes, problems, arguments,
theories, and methodologies in the field of OO micro architectural design knowl-
edge. Each chapter has been planned as a self-standing introduction to its sub-
ject.
Therefore, in Chapter I Javier Garzás and Mario Piattini present an introduc-
tion to “The Object-Oriented Design Knowledge,” where they show the main
issues and problems of the field. In OO micro-architectural design knowledge,
design patterns are the most popular example of accumulated knowledge, but
other elements of knowledge exist such as principles, heuristics, best practices,
bad smells, refactorings, and so forth, which are not clearly differentiated; in-
deed, many are synonymous and others are just vague concepts.
An essential issue to building an OO design knowledge discipline is organizing
this knowledge. In Chapter II, titled “The Object-Oriented Design Knowledge
Ontology,” Javier Garzás and Mario Piattini show an ontology that organize and
relation the OO knowledge. The authors propose an ontology in order to struc-
ture and unify such knowledge. The ontology includes rules (principles, heuris-
tic, bad smells, etc.), patterns, and refactorings. They divide the knowledge on
rules, patterns, and refactorings and they show the implications among these.
Moreover, they show an empirical validation of the proposed conclusions.
Chapter III, “Using Linguistic Patterns to Model Interactions,” by Isabel Díaz,
Oscar Pastor Lidia Moreno, and Alfredo Matteo, is a pivotal chapter that changes
the focus of the book to more technical information systems issues. This chap-
ter shows an elegant example of how highly relevant clinical questions can be
addressed in a scientific manner. In this chapter, heuristic-oriented techniques
and linguistics-oriented techniques proposed by several authors to model inter-
actions are analyzed. In addition, a framework to facilitate and to improve the
interaction modeling is described. This framework was conceived to be inte-
grated into automatic software production environments. It uses linguistic pat-
terns to recognize interactions from use case models. The validation process
used and the main results are also presented.
In Chapter IV, Manoli Albert, Marta Ruiz, Javier Muñoz and Vicente Pelechano
show “A Framework Based on Design Patterns: Implementing UML Associa-
tion,Aggregation and Composition Relationships in the Context of Model-Driven
Code Generation.” The chapter proposes a framework based on design pat-
terns to implement UML (Unified Modeling Language) association, aggrega-
tion, and composition relationships, and for it they propose a semantic interpre-
tation of these concepts that avoids the ambiguities introduced by UML.
Therefore, in “Design Patterns as Laws of Quality” Yann-Gaël Guéhéneuc,
Jean-Yves Guyomarc’h, Khashayar Khosravi, and Houari Sahraoui, Chapter
V, show how design patterns can be used as facts to devise a quality model and
they describe the processes of building and of applying such a quality model.

ix
The chapter highlights the need for principles in software engineering, where
these can be laws or theories formalizing and explaining observations realized
on software.
For the sake of completeness in this book, automatic verification of design
knowledge is addressed in Chapter VI. Andres Flores, Alejandra Cechich, and
Rodrigo Ruiz present “Automatic Verification of OOD Pattern Applications.”
Chapter VII, “From Bad Smells to Refactoring: Metrics Smoothing the Way”,
is authored by Yania Crespo, Carlos López, María Esperanza Manso Martínez,
and Raúl Marticorena. This chapter discusses one of the current trends in
refactorings: when and where we must refactor. From the bad smell concept, it
is possible to discover their existence from an objective viewpoint, using metrics.
The chapter presents a study on the relation of refactorings, bad smells and
metrics, including a case study on the use of metrics in bad smells detection.
The chapter leads to the determination where refactoring is the basis of heuris-
tics and metrics, which is likely to be the single most important factor at the
moment of use refactorings in the maintenance phase.
Therefore, in Chapter VIII, “Heuristics and Metrics for OO Refactoring: A
Consolidation and Appraisal of Current Issues,” Steve Counsell, Youssef
Hassoun, and Deepak Advani cover this topic in great depth. They look at
some of the issues which determine when to refactor (i.e., the heuristics of
refactoring) and, from a metrics perspective, open issues with measuring the
refactoring process. They thus point to emerging trends in the refactoring arena,
some of the problems, controversies, and future challenges the refactoring com-
munity faces.
A key point to building a OO design knowledge field is to understand the sev-
eral contributions to it. Since several OO metrics suites have been proposed to
measure OO properties, such as encapsulation, cohesion, coupling, and abstrac-
tion, both in designs and in code, in Chapter IX, titled “A Survey of Object-
Oriented Design Quality Improvement,” Juan José Olmedilla reviews the lit-
erature to find out to which high level quality properties are mapped and if an
OO design evaluation model has been formally proposed or even is possible.
The chapter is an excellent example of how performing a systematic review of
the estate of art.
At last, in Chapter X, “A Catalog of OOD Knowledge Rules for OO Micro-
Architecture,” by Javier Garzás and Mario Piattini, several types of knowledge
such as principles, heuristics, bad smells, and so on, are unified in a rules cata-
log.
In summary, these chapters constitute an evidence of the importance of micro-
architectural design knowledge, representing important ideas in different soft-
ware design areas. These are intended to be useful to a wide audience, includ-
ing software engineers, designers, project managers, software architects, IS/IT
managers, CIOs, CTOs, consultants, and software students.

x
We hope that the practical vision, scientific evidence and experience presented
in this book will enable the reader to use the design knowledge within the field
of software engineering and to help the field of software engineering answer
how software engineers might acquire its rich and essential accumulated knowl-
edge.
Javier Garzás and Mario Piattini, Editors
Ciudad Real, Spain
January 2006
Endnote
1
Buschmann, F., Meunier, R., Rohnert, H., Sommerlad, P., & Stal, M. (1996).
A system of patterns: Pattern-oriented software architecture. Addison-
Wesley.

xi
Acknowledgments
We would like to thank all the authors, because without their
contribution this book would not have been possible. We would
also like to thank Kristin Roth, our development editor, for her
help and encouragement.

The Object-Oriented Design Knowledge 1
Copyright © 2007, Idea Group Inc. Copying or distributing in print or electronic forms without written
permission of Idea Group Inc. is prohibited.
Chapter I
TheObject-Oriented
DesignKnowledge
Javier Garzás, Oficina de Cooperación Universitaria (OCU) S.A., Spain
Abstract
In order to establish itself as a branch of engineering, a profession must understand
its accumulated knowledge. In this regard, software engineering has advanced
greatly in recent years, but it still suffers from the lack of a structured classification
of its knowledge. In this sense, in the field of object-oriented micro-architectural
design designers have accumulated a large body of knowledge and it is still have
not organized or unified. Therefore, items such as design patterns are the most
popular example of accumulated knowledge, but other elements of knowledge exist
such as principles, heuristics, best practices, bad smells, refactorings, and so on,
which are not clearly differentiated; indeed, many are synonymous and others are
just vague concepts.

2 Garzás & Piattini
Introduction
“Chaos is order waiting to be deciphered”
~ José Saramago
Twenty years ago, Redwine (1984) commented that “an expert in a field must
know about 50,000 chunks of information, where a chunk is any cluster of
knowledge sufficiently familiar that it can be remembered rather than derived,”
adding that in mature areas it usually takes about 10 years to acquire this
knowledge. Since then, many authors (Shaw, 1990) have commented on the need
for defined chunks of knowledge in the software engineering field. In this regard,
the software engineering community has advanced greatly in recent years, and
we currently have numerous and defined chunks of knowledge, including
standards, methodologies, methods, metrics, techniques, languages, patterns,
knowledge related to processes, concepts, and so on.
Nevertheless, the field of software engineering is still beset by a lack of
structured and classified chunks of knowledge (McConnell, 2003) and not all
knowledge is transmitted, accessible or studied in the same way. For example,
what and where is the enormous amount of practical knowledge regarding
object-oriented micro-architectural design? We mean knowledge that has been
accumulated from the experience of working with the inherent properties of
software, knowledge which normally comes under what is generally accepted or
“practices which are applicable to most projects, about which there is a
widespread consensus regarding value and usefulness” (Bourque & Dupuis,
2004, p. A-10). Such knowledge may take the form of a source code, compo-
nents, frameworks, and so on, but these are no mechanisms for obtaining designs
throughout the software life cycle.
At this point, many will have already identified one of the essential items of
knowledge based on experience with object-oriented micro-architectural design:
design patterns. These are just the tip of the iceberg. Let us simplify matters and
suppose that we want to specialize as software engineers in object-oriented
design. By means of projects like SWEBOK, we can now ascertain what
“design” is, how it is subdivided, find the main bibliographical references, and so
on, and quite easily acquire a sound theoretical knowledge. If indeed we
concentrate part of our professional activity on design, we find that we need to
study the practical experience of other experts in the area, and at that moment,
the concept of pattern occurs to us. Yet, after examining the main pattern
references in object-oriented design, we still feel that something is missing.
Missing elements for the formulation of a good micro-architectural design
include principles, heuristics, best practices, bad smells, refactorings, and so on.
Table 1 gives an example of each of these.

Considerable progress has been made in the accumulation of experience-based
knowledge of OO micro-architectural design, but we have advanced consider-
ably less in its exploitation and classification. This could be seen as a case of the
“Feigenbaum Bottleneck”: “as domain complexity grows, it becomes very
difficult for human experts to formulate their knowledge as practical strategies”
(Pescio, 1997).
First, in the following section, we will analyze the maintenance and design
patterns and relationship with analyzability and changeability in more detail.
Later, we will show a measurement of the impact of the patterns used. In the last
sections, we present acknowledgments, our conclusions and future projects, and
references.
The Object-Oriented Design Knowledge
Serious difficulties are still encountered when we tackle the construction of OO
systems, especially in the transition between the analysis processes and the OO
design, an aspect which is very vague in this type of paradigm (Henderson, Seller
& Eduards, 1990). In practice, designers have accumulated a body of knowledge
Table 1. Examples of OO design knowledge
PRINCIPLES
The Dependency Inversion Principle (DIP)
“Depend upon Abstractions. Do not depend upon concretions” (Martin, 1996).
HEURISTICS
“If two or more classes only share common interface (i.e., messages, not methods), then they
should inherit from a common base class only if they will be used polymorphically” (Riel, 1996).
BEST PRACTICES
“See objects as bundles of behavior, not bundles of data” (Venners, 2004).
BAD SMELLS
Refused bequest
Subclasses that do not use what they inherit (Fowler, Beck, Brant, Opdyke, & Roberts, 2000).
REFACTORINGS
Extract Interface
“Several clients use the same subset of a class's interface, or two classes have part of their
interfaces in common. Extract the subset into an interface. [ ]” (Fowler et al., 2000).
PATTERNS
Observer
“Intent: Define a one-to-many dependency between objects so that when one object changes
state, all its dependents are notified and updated automatically” (Gamma, Helm, Johnson, &
Vlissides, 1995).

that they apply during these processes. Up until a few years ago, this knowledge
was very implicit but fortunately, it is now being specified and popularized in
different forms: principles, heuristics, patterns and more recently, refactoring,
and so on. The difference between these concepts is generally unclear and not
all of them have received the same amount of attention or have reached the same
degree of maturity.
In fact, OO design principles are often confused and few formalized. In this
regard, there are few works about it, with the exception of the contributions of
a few (Gamma et al., 1995; Liskov & Zilles, 1974; Martin, 1995, 1996; Meyer,
1997).
Regarding OO design heuristics the main works to which we can refer are those
of Riel (1996) and Booch (1996).
Patterns, however, are without doubt one of the elements that have undergone
the greatest evolution and proof of this is the existence of numerous publications
on the theme. The application of patterns in OO began at the beginning of this
decade (Coad, 1992) and was consolidated by the work of Gamma et al. (1995),
Buschmann, Meunier, Rohnert, Sommerlad, and Stal (1996), Fowler (1996), and
Rising (1998). Amongst the different types of patterns, we can distinguish,
mainly, although other categories exist (antipatterns, specific domains, etc.):
• Architectural: These focus on the structure of the system, the definition
of subsystems, their responsibilities and rules.
• Object-oriented analysis/design (OOAD): To support the refining of
the subsystems and components as well as the relationships between them.
• Idioms: They help us to implement particular aspects of the design in a
specific programming language.
As we already know, the use of patterns means that we can avoid constant
reinvention, thus reducing costs and saving time. Gamma et al., 1995 point out
that one thing that expert designers do not do is resolve each problem from the
beginning. When they find a good solution, they use it repeatedly. This experi-
ence is what makes them experts. However, at the present time, when patterns
are used, several types of problems can occur (Schmidt, 1995; Wendorff, 2001):
difficult application, difficult learning, temptation to recast everything as a
pattern, pattern overload, ignorance, deficiencies in catalogs, and so forth.
Refactoring techniques are characterized by their immaturity, although it is true
to say that this topic is rapidly gaining acceptance, the main works in this area
are Kent Beck and Fowler’s (2000), Tokuda and Batory (2001), and Opdyke
(1992).

The problem confronting the designer is how to articulate all this explicit
knowledge and to apply it in an orderly and efficient fashion in the OODA, in such
a way that it is really of use to him or her. In fact, in practice, even such advanced
subjects like patterns have this problem. Ralph Johnson comments in this sense
that “for one thing, the large number of patterns that have been discovered so far
need to be organized. Many of them are competitors; we need to experiment and
find which are best to use. …Analyzing existing patterns, or making tools that use
patterns, or determining the effectiveness of patterns, could all be good topics”
(Johnson, 2000, personal communication). These problems could give rise to
incorrect applications of the patterns (Wendorff, 2001).
The differences between these elements are not clear. Many concern a single
concept with different names, while others on occasions do not contain knowl-
edge gained from experience, and still others are simply vague concepts. This
confusion leads to a less efficient use of knowledge, so concepts such as
principles or heuristics are still unknown to some software engineers, few of
whom understand completely their goals or relationships. This problem has been
brought up at several major congresses, for example the OOPSLA 2001
Workshop: “Beyond Design: Patterns (mis)used,” where such authors as
Schwanninger (2001) say “We got more and more aware that a good description
of the proposed solution is necessary, but useless for the reader if the problem
and the forces that drive the relationship between problem and solution are not
covered properly.”
Conclusion
Expert designers have always used proven ideas. It is in recent years when these
ideas, materialized mainly into the pattern concept, have reached their greatest
popularity and diffusion. However, more knowledge exists apart from that
related to patterns, although it would be true to say that this other knowledge is
frequently “hidden.” We should consider that OO micro architectural design
knowledge is associated with the pattern concept, but other elements exist, such
as principles, heuristics, best practices, bad smells, and so forth. These other
elements show a confused description, unification, definition, and so on.
Therefore, few studies systematize and offer the OO design knowledge to
designers in such a way that it can be easily used in practical cases. In addition,
the different studies published show the elements related to design knowledge in
a disconnected way. There has not been much effort made on empirical studies
about OO design knowledge, and the few works we have found are mainly
focused on design patterns.

As Shaw (1990) states, a branch of engineering must take several basic steps in
order to become an established profession, highlighting understanding of the
nature of knowledge. We as a discipline must ask how software engineers might
acquire this knowledge.
References
Abran, A., Moore, J. W., Bourque, P., & Dupuis, R. (Eds.). (2004). Guide to the
software engineering body of knowledge: SWEBOK. Los Alamos, CA: IEEE
CS Press.
Booch, G. (1996). Object solutions. Managing the object-oriented project. Red-
wood City, CA: Addison-Wesley.
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ed.). Upper Saddle
River, NJ: Prentice Hall.

Opdyke, W. (1992). Refactoring Object Oriented Frameworks. Illinois, Urbana-
Champain.
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Wesley Professional.
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applications. Cambridge: Cambridge University Press.
Schmidt, D. C. (1995). Experience using design patterns to develop reusable
object-oriented communication software. Communications of the ACM,
38(10), 65-74.
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Paper presented at the Proceedings of the 5th
European Conference on
Software Maintenance and Reeingineering (CSMR).

Chapter II
TheObject-Oriented
DesignKnowledge
Ontology
Javier Garzás, Oficina de Cooperación Universitaria (OCU) S.A., Spain
Abstract
It has been a long time since the object-oriented (OO) paradigm appeared.
From that moment, designers have accumulated much knowledge in design
and construction of OO systems. Patterns are the most refined OO design
knowledge. However, there are many others kinds of knowledge than are
not yet classified and formalized. Therefore, we feel it necessary to define
ontology in order to structure and unify such knowledge; a good
understanding of practical experience is crucial to software engineers.
Therefore, this chapter proposes an ontology for object-oriented design
knowledge.

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different content

him to you, and on taking it away recompense him with some kernels
of corn. He will soon learn that it pays better to bring you the ear
over and over again, and be rewarded each time, than keep it
himself. Then a cob without corn may be substituted. By-and-by cobs
may be arranged in a row some foot or two apart, and the pig
required to bring some one of them you have in mind. This is the
difficult part; the pig will be inclined to pick up whichever comes
handiest. This must be prevented by gently hitting his snout, and
ordering him to “go on.” Always start him at the left of the line; you
will be able thus to guide him better than when he goes hap-hazard.
Keep on his left side, moving your foot toward him to keep him
moving in the direction of the desired article. Avoid coming between
him and the article. When he comes to it make no movement. If he
picks it up, call him to you, take it from his mouth, reward him with
corn, apple, or some other dainty, and replace the article in the row.
If, however, he passes by it, change your position to his right side,
and move your foot to urge him back.
These movements of the foot, during tuition, are, of course, more
vigorous than those used at public exhibitions. At first they merely
threaten him and drive him in the required direction, but by-and-by
he learns to observe them and to understand and profit by them. It is
possible sometimes during the lessons to help the pig’s selection by
pointing out the card or article, but this is not desirable, as it is of
course unavailable in public, and the trainer must compel the animal
to do his duty so soon as he is out of the “rudiments,” with no more
help than can be used in public.
Pigs are very fond of having their backs scratched, and this will
often attach them to their instructor, make them more docile, and
consequently more easily instructed. They are not very apt pupils,
and though they may be taught several tricks performed by dogs, it is
very seldom their education extends beyond what we have described.
We have known an exhibitor advertise a hog who would “go through
the multiplication table,” but this proved to be a catch; a hoop being
covered with paper on which the multiplication table was printed,
the hog was made to jump through it. The humor of the “sell” saved
the exhibitor from the indignation his deception might otherwise
have aroused.

In Holland, quite a number of years ago, a hog ran a race against a
fast trotting horse. The training adopted to prepare the hog for this
novel contest was a good illustration of “educating through the
stomach,” and the performance sufficiently curious, we think, to
warrant insertion here. Somewhat condensed the story is
substantially this:
A member of a sporting club at the Hague was bragging of the
speed of a certain horse possessed by him. Another member asserted
that he had a hog which he should not fear to match against him, and
this proposal, though at first laughed at as a jest, ended in a match of
six English miles, for one thousand guilders; fourteen days being
allowed the owner of Nero, the hog, for training; and the horse to
carry two persons. The course selected was the avenue leading from
the Hague to the sea shore at Scheveningen; the hour, eleven o’clock.
The first day’s training consisted in giving Nero nothing to eat. On
the second day, at eleven o’clock, his master appeared, and fastening
a rope securely to one of Nero’s hind trotters, drove him, with many
a kick and forcible persuasion all the way over the course of
Scheveningen. Here Nero received two herrings, which he ravenously
devoured. It is said that hogs—or at least Dutch hogs—prefer fish to
any other food. On this scanty meal Nero had to tramp home.
The third day the hog was ravenous, but had to bide his time till, at
eleven o’clock, his master presented himself for another trip to the
course. After a liberal and energetic application to the booted foot,
and a little loud and angry discussion between the two parties, they
arrived at their journey’s end, where Nero was regaled with three
herrings, being one extra, which he dispatched voraciously in double
quick time, looking for more, but in vain. He was then, with much
coaxing and kicking, persuaded to resume the return trip homeward,
and which was safely accomplished, although not without
considerable opposition, accompanied by vigorous squealing and
determined grunting on the part of Nero.
On the fourth day, when his master presented himself, Nero
seemed to understand somewhat the object of his calling; he walked
off, not only without compulsion, but with considerable alacrity, at a
good round pace to get to his journey’s end, where his master regaled
him not alone with his coveted dinner of three herrings, but, as a
reward, yet another herring extra. On the fifth day Nero was fully up

to the game, and his master experienced considerable difficulty to
keep up with him. At Scheveningen the usual allowance—now of four
herrings—was placed at his disposal, and disposed of by him in short
meter.
On the days following, and up to the time of the race, his master
had no farther difficulty with Nero, but to keep up with him, Nero
invariably taking the lead, although on the return trips the same
difficulties always recurred. A vigorous application of boots was in
such cases the only convincing argument with Nero, who never could
see the point nor comprehend the necessity, of this back-track
movement, and ever obstreperously squealed or grunted his
objections. On the ninth day Nero had become perfectly trained, and
having grown extremely thin upon his scanty meals, he now ran like
a race-horse, invariably distancing his master, who followed with a
fast trotting horse in harness. Both exercise and spare diet were,
however, strictly adhered to up to the day preceding the one on
which the race was to come off. On that, the thirteenth day, as on the
first day, poor Nero was again starved. At the usual hour of eleven his
master appeared, but Nero was doomed to disappointment—no trot,
no herrings on that day. With eager eye and impatient grunt he
signified his desire to be released from his pen; but, alas, it was not
to be.
On the fourteenth day both horse and hog appeared at the starting
post, eager for the race. It was a beautiful day, and the road was lined
the entire distance, on both sides, with anxious and delighted
spectators eager to see the sport. Punctually at eleven o’clock, at tap
of drum off they started, amidst the shouts and hurrahs of the
multitude. The first two miles were closely contested—it was
emphatically a neck and neck race; but Nero, light as feather, and
having in his mind’s eye, probably, his delectable meal, now fairly
flew over the course, gradually leaving the horse behind, keeping the
lead the entire distance. Amidst shouts and hurrahs, the waving of
handkerchiefs, and the wildest excitement, he reached the winning
post, beating the horse by half a mile, and winning the race
triumphantly.
For this extraordinary performance, Nero was rewarded with a
pailful of herrings, which, having feasted upon to his heart’s content,
he waddled back to the Hague, in the care of his master, “the

admired of all admirers.” His master, pocketing the purse of one
thousand guilders, generously spent one hundred guilders for Nero’s
portrait, which is now preserved at the sportsman’s club at the
Hague.
It is said that hogs may be taught to destroy thistles. The tuition
consists only in trampling them down, mashing the buds, and
sprinkling salt thereon. The hogs eat these at first on account of the
salt, but in so doing they acquire a relish for the thistles themselves,
and this taste once acquired the thistles are eagerly sought for and
devoured. It is claimed that one hog that has been taught in this way
will teach all others in the drove. Possibly seeing him eat they
imagine they are losing a treat and so eat too. If this statement
proves true, the hint may be useful to farmers.

I
CHAPTER XVII.
PERFORMING MONKEYS—MONKEY
EQUESTRIANS—THE “WONDERFUL
CYNOCEPHALUS”—MONKEY ACTORS, ETC.
n training performing monkeys the instructor is greatly aided by
that imitative faculty which is a characteristic of the whole
monkey family. The intense passion a monkey has for mimicking the
actions of persons is well known, and to such an excessive degree is
this passion sometimes possessed that several instances are on
record of their cutting their own throats while attempting to shave
themselves, having observed some man performing that operation. It
is this imitative instinct which is taken advantage of in preparing
monkeys for public exhibition. Indeed, their instruction consists
mainly in the teacher performing the act himself, for the monkey to
copy. This is the case with such tricks as taking off the hat, fencing
with a little tin sword, sweeping with a little broom, and the like.
During his instruction the pupil has a small leather belt around his
body, to which is attached a cord several yards in length, which the
trainer holds. The first thing taught is usually standing on the hind
legs; this is done by holding the cord taut and the gentle application
of a switch under the chin. This is not a natural position, still the
animal can maintain it with comparative ease. Walking the tight rope
is also easily accomplished, and furnished with a light balancing
pole, he will go back and forth under the guidance of the “leading
string” before mentioned. Jumping barriers or leaping through
hoops held in the trainer’s hand, is taught by jerking the string and
giving the monkey a slight cut with the whip. Hoops covered with
tissue paper, or balloons, as they are technically called, may be

substituted for the open ones after a few lessons, and add to the
attractiveness of the performance.
Dressed in male or female apparel, the monkey’s naturally comical
appearance is greatly hightened. Thus, one may be dressed to
represent a lady of fashion, while another personates her footman,
who, dressed in gorgeous livery, supports her train. This is
elaborated into quite a little scene at some exhibitions. A little
barouche, drawn by a team of dogs, is driven on the stage, a monkey
driving while a monkey footman sits solemn and erect upon his
perch behind. A monkey lady and gentleman are seated inside, she
with a fan and parasol, and he with a stovepipe hat. Around the stage
several times the equipage is driven, until by-and-by one of the
wheels comes off and a sudden stop results. Down the footman
comes, opens the carriage door, assists gentleman to hand out lady—
who has fainted in gentleman’s arms just as she ought under these
trying circumstances, and in a style that would do credit to any belle
in a similar accident at Central Park—gets chair from side of stage for
her to sit in, while gentleman fans her till she gradually recovers.
Coachman meantime gets down and goes after the lost wheel, which
he rolls to the vehicle and places therein; then mounting his box,
drives off, for repairs it is presumed. By this time the lady has
recovered, takes the arm of her escort and follows after the carriage,
while the footman brings up the rear, carrying the chair.
MONKEY “MUSICIANS.”

This is apparently quite a complicated performance, but is not
particularly difficult. Each performer is taught what he is to do, the
most intelligent monkey being generally assigned the footman’s
character. The dogs are taught to run around until the wheel comes
off; this is their signal to stop. In teaching the monkeys their parts a
portion only of the scene is taught at first; thus some days may be
consumed in merely making the actors occupy their appointed
positions properly—such slight improprieties as the footman
jumping down upon the heads of the lady and gentleman, or the
gentleman pulling the driver off his seat by the tail, or the lady
banging her cavalier over the head with her parasol, and like
exhibitions of playfulness, being checked by applications of the whip.
Gradually the “business” of the scene is built up—each lesson
including all performed up to that time and a little in advance; nuts,
bread and an occasional bit of candy, being the rewards for success,
and whip for failure therein. Each monkey knowing his name, and
being called upon by name when his turn comes, he by-and-by learns
the proper time to perform his assigned work without any
prompting.
The equestrian performances on pony or dog-back, styled “steeple
chases,” and like tricks usually exhibited, scarcely require notice
here. However amusing they may be it can hardly be said that the
monkey’s part of the exhibition requires much of either intelligence
or training, as he is usually strapped upon his steed and cannot very
well help staying there. Sometimes, however, instead of tying the
monkey in the saddle, a perch is erected on the fore part of the
saddle, to which he clings frantically as the dog or pony rushes
around the ring. This is no great improvement upon the strap, and
the only training the monkey gets is a cut from the whip whenever he
permits himself to be dislodged. For a trainer to break a monkey so
as to ride a horse, carry a miniature flag, and hold on by the reins, is
commonly considered a remarkable achievement. Occasionally
though a monkey rider has been exhibited who has really performed
in a manner not merely absurd. The most notable example of this
kind was a huge ape of the cynocephalus or dog face family, exhibited
in the winter of 1867–8 at Lent’s New York Circus, under the title of
the “Wonderful Cynocephalus.”

Monsieur Olivier, a French circus manager, had taken a troupe to
India on speculation a short time previous to the Sepoy mutiny, on
the breaking out of which his company disbanded, many joining the
English troops. The manager then wandered in search of an opening
for professional speculation, and while so doing attempted the
training of several varieties of the monkey tribe. His success was by
no means encouraging until, after years of failure, he came across the
individual who is the subject of this sketch. The Cynocephalus was
captured in Zanzibar, on the east cost of Africa, and from the first
exhibited unusual intelligence, and after many months of patient
training he was prepared to shine among equestrian stars. His débût
was made at the Cirque Napoleon, where he immediately achieved
celebrity. His performances afterward repeated in New York were
equally successful, and a brilliant career was anticipated for him.
Preparations had been made for his exhibition throughout the
country, with the circus to which he was attached, but a week or two
previous to starting on the summer tour the Cynocephalus was
attacked with inflammation of the bowels, and though he rallied, and
hopes were entertained of his recovery, he died some days before the
time appointed for the start.
THE “WONDERFUL
CYNOCEPHALUS.”

Of his achievements in the ring it is only necessary to say that he
went through all the feats usually displayed by a circus-rider,
jumping upon the horse, standing on one leg, then holding the other
in his hand, then standing on his head, following this by somersaults,
and finishing off with the customary vaulting through balloons and
over banners. There was all the while a gravity of demeanor and
seriousness of countenance contrasting favorably with the self-
satisfied smirks and meaningless grins of his human compeers.
As regards his tuition, each act had been taught separately, the ape
with a cord attached to a collar around his neck and the other end
held by his master, being placed in the required position, the horse
was then started, and in each instance where the ape quitted his
position before the horse was stopped, a cut from the whip was
administered; every time the ape retained the position till the horse
had gone a certain number of times around the circle, he was
rewarded with a sweetmeat. Each time a change of position was to be
made, which was always after a particular number of “rounds,” the
horse was stopped and the ape made to take the new posture. These
attitudes followed one another in regular sequence, and soon a mere
change in the music was substituted for the stoppage each time the
horse had been around the customary number of times. A hint from
the whip was sufficient to remind the ape that he was to make a
change. The banner and balloon tricks were readily taught by making
him first leap them, when offered, while the horse was standing still,
and afterward when in motion. The system of reward or punishment
for success or failure was always kept up, and in his public
performances a close observer would have noticed at any failure a
frightened look from the ape and a sly cut of the whip, while after
each successful feat a little sweetmeat was received from the pocket
of the ring-master.
A very popular scene at exhibitions of performing animals is that
in which a number of monkeys are seated around a table, spread for
a feast. Two or three monkeys personate waiters and bring in, first
candles, and then in succession the various courses, really consisting
of things suited to monkey stomachs, but considered by theatrical
license to be the customary viands of a grand feast. Bottles of water-
wine conclude the repast. This is actually one of the simplest things
for the trainer to accomplish. The guests being tied in their high

chairs, their little bibs pinned around their necks, the only farther
trouble with them is to keep them from fighting or stealing each
other’s rations. The waiters bringing in the things, especially the
lighted candles, look very pretty and very intelligent. This part is
taught by having two strings attached to the monkey. The end of one
of these strings is held by the trainer, the end of the other by an
assistant off the stage. The assistant places an article in the monkey’s
paw and slacks up his line, while the trainer hauls in on his, and by
this very simple arrangement, first one and then the other hauling,
the monkey learns to make the passage to and from the stage. Should
he drop his load before reaching the person to whom he is traveling,
a long whip-lash reminds him of his mistake, and the article is
replaced in his hand, or he kept by it until he picks it up. It doesn’t
take long to teach him that when he is given an article by one of his
“workers” he is to take it to the other, and then the strings may be
dispensed with, though a fine but strong twine is sometimes used
even in public exhibitions, and we recall one occasion at a New York
theater where the waiter got the twine entangled in some
impediment and was held midway till released by the exhibitor.
Though the twine could not be seen by the audience, the cause of the
difficulty was too obvious to be mistaken, and some rather sarcastic
applause was bestowed. On another occasion, in a neighboring city,
we witnessed a squabble among the monkey guests, a general
clawing and biting, ending with the upsetting of the chairs and the
scampering off of the monkeys with chairs “hitched on behind.”
The “drill exercise,” performed with a little musket, which the
monkey fires off at the close, is a common but always popular
exhibition. Any one who has seen a green recruit “put through” by
the drill-sergeant can form a pretty correct idea of the method of
training pursued in the case of the monkey. The instructor takes the
required positions himself, using his whip in lieu of a musket, giving
the word of command as he does so. Until the monkey understands
these orders the trainer places his musket in the right position for
him whenever he fails to do it himself. In case of willful disobedience
or obstinacy, the whip is restored to its primary use, while good
conduct is rewarded with equal promptness.
Sham fights are sometimes arranged for a number of monkeys. In
this performance each monkey is taught his particular part, and

rehearses it with the trainer till thoroughly familiar with it; then each
monkey rehearses with the one with whom he is to act, until, as all
become perfect in their parts, the whole act together. In rehearsing
the monkeys perform each action at the word of command, being
called by name. The mimicry natural in monkeys has here to be
checked, otherwise the performance would be thrown into confusion
by each copying the other’s acts. The monkeys are, therefore,
punished for any movement without orders, or for responding when
another’s name is called.
To be trained successfully, monkeys must be taken when young,
and the degree of docility and intelligence varies greatly with
different species. The entellus monkey, a slender and graceful native
of the Indian Archipelago, whose light fur makes a strong contrast
with its black face and extremities, exhibits great gentleness and
playfulness when young, but these traits change, as it becomes older,
to distrust and listless apathy, and, finally, it becomes as mischievous
as others who have never displayed any particular indications of
good temper.
Some varieties seem to possess the ability to actually plan and
carry out quite complicated operations, which, in a state of nature,
are as remarkable as any of their performances in captivity. The
mottled baboons display this in their robberies of the orchards of
their native country. A part enter the enclosure, while one is set to
watch, and the remainder of the party form a line outside the fence,
reaching from their companions within to their rendezvous in the
neighboring woods. The plunderers in the orchard throw the fruit to
the first member of this line, who throws it to the next, and so it is
passed along until it reaches headquarters, where it is safely
concealed. All the time this is being done the utmost silence is
maintained, and their sentinel keeps a sharp lookout. Should any one
approach he gives a loud cry, at which signal the whole company
scamper off, though always taking a load of fruit in their retreat, if
possible, in their mouths, under their arms, and in their hands. If
hotly pursued this is dropped piecemeal, but only when absolutely
necessary to enable them to escape.
As the disposition varies with different species, so also must the
system of training. While one will require considerable severity,
another can be made to perform only by being well treated and

liberally rewarded. Once at the old Broadway theater, in New York, a
very celebrated monkey stopped in the middle of a tight-rope
performance and refused to continue. His master threatened,
scolded, and finally flogged him very thoroughly, but he only
jabbered and howled, and could not be made to finish his
performance; his master ending by taking him in his arms and
carrying him off the stage.
Many monkeys have a great liking for strong drink, and this
weakness is frequently taken advantage of by other trainers to induce
them to perform; a bribe of a little liquor often proving a more
powerful incentive than anything else. A mandril, who, at one time,
created considerable excitement in London, where he was exhibited
under the title of “Happy Jerry,” was a remarkable example of
monkey devotedness to the rosy god. Gin and water was his besetting
weakness, and to obtain it he would make any sacrifice or perform
anything within the bounds of possibility. In some instances sugar
brandy-drops are used in public exhibitions as rewards, though this
is done sparingly.
Besides these weaknesses of appetite, to which their trainers
appeal, monkeys have a fondness for petting. Jardine mentions one
of the shooloch species who was particularly pleased with caresses.
He would lie down and allow his head to be combed and the long
hair of his arms to be brushed, and seemed delighted with the
tickling sensation produced by the brush on his belly and legs.
Turning from side to side, he would first hold out one limb and then
the other.

BABOON FINDING
WATER ROOTS.
It is rare that any of the monkey tribe have been made available for
any really useful purpose. Occasionally, we believe, they have been
made to turn spits, and one case is recorded of a monkey on
shipboard who was taught to wash dishes and perform several other
of the minor duties of the culinary department, under the
supervision of the cook. Among the Kaffirs of Africa a particular
species of baboon, the chacma, is trained for a somewhat novel
purpose. These chacmas will eat anything a man will, and torment
the natives grievously by pillaging their gardens. The tables are,
however, in some cases turned, and the chacmas made to provide
food for the Kaffirs instead of deriving it from them.
The ordinary food of the chacma is a plant called babiana, from the
use which the baboons make of it. It is a subterranean root, which
has the property of being always full of watery juice in the driest
weather, so that it is of incalculable value to travelers who have not a
large supply of water with them, or who find that the regular
fountains are dried up. Many Kaffirs have tame chacmas which they
have captured when very young, and which have scarcely seen any of
their own kind. These animals are very useful to the Kaffirs, for if
they come upon a plant or a fruit which they do not know they offer it
to the baboon, and if he eats it they know that it is suitable for
human consumption.
On their journeys the same animal is very useful in discovering
water, or, at all events, the babiana roots, which supply a modicum of
moisture to the system, and serve to support life until water is

reached. Under these circumstances, the baboon takes the lead of the
party, being attached to a long rope, and allowed to run about as he
likes. When he comes to a root of babiana he is held back until the
precious vegetable can be taken entire out of the ground, but, in
order to stimulate the animal to farther exertions, he is allowed to eat
a root now and then.
The search for water is conducted in a similar manner. The
wretched baboon is intentionally kept without drink until he is half
mad with thirst, and he is then led by a cord as before mentioned. He
proceeds with great caution, standing occasionally on his hind legs to
sniff the breeze, and looking at and smelling every tuft of grass. By
what signs the animal is guided no one can even conjecture; but if
water is in the neighborhood the baboon is sure to find it. So,
although this animal is an inveterate foe of the field and garden, he is
not without his uses to man when his energies are rightly directed.

R
CHAPTER XVIII.
RATS—MICE—FROGS—TOADS—FLEAS, ETC.
ats generally are not favorites. There seems to be born in the
human race a natural antipathy to these animals, and the
preference with most persons would be rather to exterminate them
than to attempt to tame them. Still rats may be tamed, though it
must be confessed they are rather unattractive subjects, their odor
being disgusting and their bite poisonous, probably from particles of
putrid flesh adhering to their teeth—in many recorded cases fatally
so.
Probably most readers have heard the story of the Frenchman, we
forget his name, who was doomed to expiate some political offense in
a dungeon cell; and how, to relieve the dreary loneliness and
torturing monotony of his solitary existence, he strove to win the
confidence of a rat which stole timidly forth from some crevice to
pick up the crumbs dropped by the prisoner from his frugal meals.
By slow degrees he labored to achieve his purpose, dropping a few
crumbs on the floor and waiting motionless till the animal had come
from his retreat and taken them; then, as the rat’s timidity gave way
under the influence of this kindness, the man enticed him to eat from
his hand, to climb up his leg into his lap, and by-and-by to permit
himself to be handled, until at last the rat would nestle in the man’s
bosom, come at his call, and in many ways display his affections for
his master.
Mice are less ferocious than rats, more easily managed, and also
make better performers, if it is desired to teach them tricks. The
process of training is the same with both. In securing your captive, a
trap which does it no injury should be used. To say nothing of the
cruelty, an animal that is partially disabled or suffering pain, is not in
a condition to learn well. The best traps are those in which wires are

so arranged as to permit an easy entrance while they present an
array of sharp points to prevent an exit.
The first thing after the capture is to tie a piece of fine but strong
twine to the captive’s tail. This may be done without removing from
the trap, or a wire or tin cage; he should be kept until so far tamed
that he will not attempt to gnaw the string and escape when taken
from his prison. During this time he should be well treated, supplied
with food and water, and in no way irritated or alarmed. At the end
of a day or so he may be allowed to come out upon a table, while the
string which retains him is held securely. He will, probably, run
around to examine the locality and then make an attempt to escape.
At this point he must be gently but firmly drawn back, and we would
advise that the first lesson consist merely in teaching him the
uselessness of these attempts. At the next lesson a light wand, of
willow or other wood, about twenty inches long, should be provided.
Shortening the confining string so as to have your animal “well in
hand,” you make him travel back and forth across the table in a
straight line several times, guiding him by placing your wand in his
way whenever he swerves from the correct course. Then make him go
in a circle, then along a piece of board, or books laid on an edge, and
any other convenient exercises to habituate him to follow your
guidance. Remember, in doing this, that your object is to teach him—
not to torment him. This wand is the real key to the performances of
rats and mice. Though, these animals, doubtless, possess
considerable sagacity, nearly all the tricks we have ever seen them
perform have been mere obedience to the guidance of the exhibitor;
so that when your pupil will go in the desired direction at the
slightest hint with your wand, the main part of his training is
accomplished, and you have only to arrange various little tricks in
which the obedience will come in play.
By placing an obstacle in his way of such a shape as he cannot
readily climb over, and urging him forward, he may be taught to
leap; soon little hoops of wire or wood may be held for him to jump
through, and these may be raised gradually with successive lessons
until he will spring a considerable distance into the air to go through
them. During all the time of training it should be your object to tame
your pupil and inspire him with confidence in you; this will enable
you eventually to remove the string which secures him, and so add to

the credit of your exhibition. He should also be accustomed to take
food from your hand or from the point of a bit of stick. This will serve
as the foundation of many amusing tricks. Thus a small piece of
cheese may be placed on the end of a string or wire so arranged that
the removal of the cheese will cause a little bell to ring or produce
some other pleasing effect. After the first few lessons with this
arrangement, in which the mouse will have become accustomed to
securing his food in this way, the cheese may be simply rubbed on
sufficiently to induce him to bite at it. He should at first be guided up
to it with the wand and tapped gently under his chin to induce him to
rise and seize it. A variation of this is the trick of carrying articles in
his mouth. First give him some article thoroughly smeared with
cheese; the desire to secure the cheese will make him take it; then by
urging and guiding him with your wand you can make him carry it
about; being loth to relinquish the cheese, he will retain the whole.
The amount of this bait used may be gradually diminished. By-and-
by he may be made to convey little articles to and fro between two
persons seated at opposite sides of the table. To do this, as well as for
general convenience, it is well to accustom your pupil to come to you
at some particular sound. This may be either the snapping of the
finger nails or some slight noise of the mouth. It is easily done by
making the noise, and, at the same time, pulling him toward you by
the string attached to his tail. When he reaches you reward him with
a morsel of cheese or bread, and repeat from day to day until he will
come upon hearing the call.
Rats or mice may be used as motive powers to operate little models
of machinery. This requires no training, as they are merely placed in
a tread-mill contrivance, and being kept there their weight causes the
works to move and compels the animal to keep up the motion.

RAT AS A MOTIVE POWER.
A little performance, a la Blondin, may be arranged for your mouse
by stretching a piece of wire sufficiently stout to afford him a firm
foothold, from two posts, about a foot in hight, fastened into a board.
The ends of the wire may be at an angle, and also be secured to the
board. Being guided by your wand up the slanting wire upon the
main one, the dexterity with which he will run about upon it is quite
surprising. If he has been already taught to hold things in his mouth
he may be given a piece of wood, about the thickness of an ordinary
friction match and twice its length, to represent a balancing pole, and
this may be adorned at each end by a balancing flag or bit of ribbon.
The real “balancer,” however, is the animal’s tail, which he will
wriggle from side to side to preserve his equilibrium.
In the summer of 1867 one of the most attractive of the outdoor
shows exhibited in Paris was that of “the man of rats,” well known to
the inhabitants of the Quartier Mont Parnasse, where he has held his
headquarters for the last thirty years. The name of this Rarey of the
rat race is Antoine Leonard. If the former succeeded in breaking in
the worst tempered brute ever created, Leonard in three weeks
certainly accomplished the difficult task of cultivating habits of
obedience in the biggest rats that ever ran. His favorite scenes of
action are some cross alleys in the 14th and 15th Arondissement. His
sole theater is a sort of perch which he sticks into the ground, and
then he takes his corps de ballet out of his pocket. At his word of
command the rats run up and down the perch, hang on three legs,
then on two, stand on their heads, and in fact go through a series of

gymnastic exercises that would put Blondin himself to the blush. His
crack actor is a gray rat that he has had in his troupe for eleven years.
This old fellow not only obeys Leonard, but is personally attached to
him. It is a most curious sight to see Leonard put him on the ground,
and then walk away. The creature runs after him, and invariably
catches him however many turns he may make to avoid him. An
Englishman offered fifty francs for him about two years ago, but
Leonard would not separate from his old and attached friend.
Some time ago, in passing through Beekman street, in this city, our
attention was attracted by quite a large crowd gazing intensely at the
telegraph wires which pass through the street. Following the example
of the rest, we at last discerned, high up on the topmost wire, a
mouse, that was running along evidently in search of some safe
descent from his novel position. It seems that some boy had caught
him, and the fact that the wires in that vicinity pass close to the
windows of the buildings, had, doubtless, suggested the idea of
placing him thereon. Whether the mouse would have persevered and
traveled on to Albany, thus furnishing an example of sending articles
by telegraph, it is impossible to say, for some person at a window
within reach of the wire, by vigorous shaking, succeeded in
dislodging him, and he fell to the ground among a crowd of boys who
were eagerly waiting to receive him. In the scramble that followed he
was captured, and borne off in triumph by a newsboy.
A shrewd dodge is related by a New York paper of a certain saloon
keeper, who has been greatly annoyed by persons who sit about in
chairs to sleep off the effects of bad whiskey. He has caught and
tamed several rats, and trained them to run across the floor. A sitter
wakes up and sees the rats running, and calls attention to the fact,
when he is told there are no rats there. This frightens the man, who
thinks he has got the tremens, and he quickly disappears from the
saloon.
Frogs are made pets of in some countries. In Vienna may be seen
gilt cages containing small frogs of a pretty green color, which are
kept in drawing rooms, and amuse by their gambols. Curious stories
are told of the domestication of the tree-frog, which is a native of
warm countries. It is said of Dr. Townson, that he had two pet frogs
of this variety. He kept them in a window, and appropriated to their
use a bowl of water, in which they lived. They grew quite tame; and

to two which he had in his possession for a considerable time, and
were particular favorites, the doctor gave the names of Damon and
Musidora. In the evening they seldom failed to go into the water,
unless the weather was cold and damp; in which case they would
sometimes abstain from entering it for a couple of days. When they
came out of the water, if a few drops were thrown upon the board,
they always applied their bodies as close to it as they could; and from
this absorption through the skin, though they were flaccid before,
they soon again appeared plump. A tree-frog, that had not been in
the water during the night, was weighed and then immersed; after it
had remained half an hour in the bowl, it came out, and was found to
have absorbed nearly half its own weight of water. From other
experiments, it was discovered that these animals frequently
absorbed nearly their whole weight of water, and that, as was clearly
proved, by the under surface only of the body. They will even absorb
water from wetted blotting-paper. Sometimes they will eject water
with considerable force from their bodies, to the quantity of a fourth
part or more of their weight. Before the flies had disappeared in the
autumn, the doctor collected for his favorite tree-frog, Musidora, a
great quantity as winter provision. When he laid any of them before
her she took no notice of them, but the moment he moved them with
his breath she sprang upon and ate them. Once, when flies were
scarce, the doctor cut some flesh of a tortoise into small pieces, and
moved them by the same means; she seized them, but the instant
afterward rejected them from her tongue. After he had obtained her
confidence she ate from his fingers dead as well as living flies. Frogs
will leap at the moving of any small object; and, like toads, they will
also become sufficiently familiar to sit on the hand, and submit to be
carried from one side of a room to the other, to catch flies as they
settle on the wall. This gentleman, accordingly, made them his
guards for keeping the flies from his dessert of fruit, and they
performed their task highly to his satisfaction.
Another, yet more remarkable frog, is told of by a Virginia
gentleman: “Concerning this frog,” says he, “it has lived many years
with us and is a great favorite, and the greatest curiosity is its
becoming so remarkably tame. It had frequented our door steps
before our hall door some years before my acquaintance commenced
with it. My father had admitted it for years on account of its size and
color, and he visited it every evening, when it would come forth at his

summons, and by constant feeding he brought it to be so tame that it
would come to him and look up as if expecting to be taken up and
brought to the table and fed on insects of all sorts. On presenting
living insects it fixes its eyes intently and remains motionless for a
while as if preparing for a strike, which is an instantaneous throwing
of its tongue to a great distance, upon which the insect sticks fast to
the tip by a glutinous matter. I can’t say how long my father had been
acquainted with it; from my earliest recollection he spoke of it as ‘Old
Tom,’ ‘the old frog.’ I have known it for a great number of years—I
can answer for fifty-seven years. It makes its appearance (always a
welcome visitor) with warm weather and remains with us till fall,
appearing morning and evening to our great amusement, having
been trained to do many things, such as leaping, turning somersaults
holding alternately by its feet and hands to a small rope, swinging
and whirling, after the manner of a slack rope performer, marching
erect oh its hind legs, and at the word of command going through the
manual exercise. It seems perfectly good natured, and never shows
temper, but is dreadfully afraid of a cat, on whose approach it will
often leap four feet from the floor, with the utmost precision, plump
into the mouth of a large stone water pitcher, and thus secure a safe
retreat. Yet it is in no wise alarmed or disturbed by the presence of
dogs, of which we have many about the premises. They all seem to
regard it as one of the household and a ‘privileged character.’”
Were not this story apparently well attested we might doubt some
of the details, as our own experience has shown that, while frogs are
easily tamed, and may be taught quite readily to perform such simple
feats as leaping, clinging to a string while swinging, and the like, they
yet seem to possess no aptitude for learning any more elaborate
feats. Some of our readers may, perhaps, be as successful as this
gentleman was, and in that case we should be pleased to have them
let us know of it.
It may easily be imagined that the capture and training of fleas
would require a patience almost rivaling Job’s, and a skill which, in
its particular way, might almost be called a triumph of genius. Yet
that has been done, and some years ago a man gave exhibitions of
what he termed “educated fleas,” which were quite popular and
successful. This man was a German, who, at the time we speak of,
was somewhat more than sixty years of age, and had been, with true

Teutonic steadfastness, about twenty years engaged in his strange
vocation. Fortunately he was endowed with a sharp pair of eyes,
which not only enabled him to keep track of his little performers,
over three score in number, but also to make the minute “properties”
used in the exhibition.
This “artist in fleas” took considerable pains to secure choice
specimens for his collection, and had arrangements whereby they
were forwarded to him by mail, carefully packed in cotton, from
localities noted for their superior breeds. When not in use the fleas
are packed away in pill-boxes between layers of cotton. They are fed
twice each day; the manner of feeding being to allow each to suck
one drop of blood from the trainer’s bare arm. This would be an
ordeal few of our readers would probably care to submit to, but the
hero of the sixty fleas had become so accustomed to it that he didn’t
mind it in the least, and, for aught we know, rather enjoyed it.
The intelligence of fleas is not of a very high order, and their
“education” is really very limited; the seeming marvels they perform
being mainly clever management on the part of their exhibitor.
When first received they are secured with a halter of the finest
imaginable silk to prevent escape. The first thing they are taught is
not to jump. For this purpose the end of the halter is secured to a pin
in the table, and each jump naturally results in the prisoner being
upset with a sudden jerk, with, no doubt, a rather unpleasant
sensation about the neck. Sometimes a sharp pressure upon certain
muscles is resorted to for checking this jumping propensity. Being
well fed and well treated, when it behaves itself, even a flea will
become tame. Punishment, too, for rebellious conduct is also
practiced. As fleas are not well adapted for being flogged a new
device is resorted to, a piece of burning charcoal, or heated wire, is
held over them until they are subdued.
The usual performances consist in little coaches being drawn
about by fleas harnessed up, while others of the troupe personate
riders, coachmen and footmen. Then there is the ball-room scene,
where fleas waltz around to the imaginary music of an orchestra of
fleas, furnished with minute imitations of various instruments. There
are also quite a variety of other tricks, but they are all pretty much
the same in principle. The main secret in these performances is a
piece of very thin wire, some ten or so inches in length, which the

exhibitor holds in his hand during the entertainment. The end of this
wire is greased with butter, which appears to possess a strong
influence upon the fleas, for they will eagerly follow the wire in
whatever direction it is moved. The audience, ignorant of this fact,
attach no importance to the exhibitor’s directing with it the
movement of his performers, and may even consider their following
it a proof of superior training. By this means the fleas may easily be
made to go through the desired movements.
Where the fleas occupy a stationary position a trick is resorted to
which if on a large scale would be clumsy, but which in this instance
defies the sharpest eyes to detect. The insects are fastened in their
positions. Aided by the costumes with which they are encumbered,
this is not difficult to accomplish. Natural movements are also made
to pass for seemingly wonderful effects. Thus the performance of the
musicians is nothing but the customary wriggling of the fleas. Any
insect in a confined position will seize hold of a light article whether
it be shaped like a fiddle or not, and twirl it about. With the fleas it is
impossible for the spectator to distinguish exactly what the motion is
—it is so rapid and everything is so small—and imagination makes up
for a good many deficiencies.
We have seen boys amusing themselves impaling a fly, belly
upward, upon the point of a pin, the head of which was inserted in a
cork standard, and giving him a little dumb-bell composed of pieces
of cork connected by a piece of hog’s bristle. The fly would grasp this
in his agony, and his convulsive movements would have a very exact
resemblance to a dumb-bell performance, and be irresistibly
ludicrous, however much one might sympathise with the victim’s
suffering. It almost rivaled the professor and his fleas.
Once upon a time this troupe of fleas were exhibited at Berlin
before the king and queen. The professor was suddenly seen to
exhibit signs of great consternation. “What is the matter, Herr
Professor?” inquired his majesty, on seeing that the performance had
come to a stand still. “Sire, I perceive that one of my very, best
performers, the great Napoleon, has got loose and disappeared.” “Let
search be made at once for the great Napoleon,” replied the king,
good humoredly. “Ladies and gentlemen, let the Herr Professor have
your best help in recapturing the great Napoleon. In what direction,
Herr Professor, do you imagine the runaway to have gone?” “If I may

venture, sire, to reply frankly,” returned that personage, “I suspect
the great Napoleon to have secreted himself about the person of her
serene highness, the Princess F——.” The “highness” thus named,
feeling anything but “serene” at the thought of affording quarters to
such an intruder, made a hasty retirement to her own apartments,
whence, after a brief retirement with her cameriste, she smilingly
returned to the royal presence, bringing some object held delicately
between her thumb and finger, which she cautiously made over to
the professor. “Alas! sire,” exclaimed the latter, after a moment’s
glance at what he thought was his discovered treasure, “this is a wild
flea and not the great Napoleon!” And the exhibition was brought to
an ignominious conclusion.
We once heard of a performance somewhat akin to our professor’s.
At a certain boarding school that we attended years ago, we noticed
our room-mate one morning examining the bed in a manner to
indicate beyond doubt that he was in search of an insect which is not
usually a subject of conversation in polite society. Fortunately for the
credit of the school he found none. In answer to our expression of
surprise at his evident disappointment at there being none, he
explained that he wanted to show us a splendid trick he had invented
at home; and he went on to describe how he had often amused
himself by gluing one end of a string to the back of an unfortunate
bug, while to the other end was hitched a miniature model of a cart,
made of paper. This, he said, was capital sport, especially when he
made two of these teams race, and pricked the steeds with a needle
to make them lively. This is the only example of bed-bug training we
are able to record.
A very useful thing for farmers is the power of handling bees
without liability to be stung. Many persons imagine this to be some
gift or mysterious influence possessed by the successful operator,
while others suppose it to be derived from some wonderful secret
possessed by him. Though this “secret” is really quite a simple
matter, the fact that a speculator has been selling it to bee keepers at
the modest price of ten dollars, shows that it is an interesting subject,
and we propose to give it to the reader without exacting any fee.
Let us suppose you have a particularly irritable colony in one of the
modern hives, from which you desire to obtain the honey. The
treatment must vary a trifle according to the particular design and

arrangement of the hive, but the following directions, with very slight
modifications, will answer for all. First confine the bees in the hive,
and rap on the side of it with the palms of your hands or a small
stick. The first efforts of the bees will be to escape from the hive;
finding this impossible they will rush to their stores and fill
themselves with honey. Should the rapping prove insufficient to
frighten them and cause them to fill themselves with honey, smoke
from rotten wood, which is the best, cotton rags, or tobacco, may be
made to enter the hive which will have the desired effect. Bees will
never sting of their own accord when gorged with food, and in this
condition may be handled with impunity.
When swarming, or out of the hive for any reason, they may be
“tamed” by placing water well sweetened with sugar within their
reach. Bees can never resist the temptation and after they have
gorged themselves with this preparation they are as harmless as
when their sacks are filled with honey.

O
CHAPTER XIX.
“HAPPY FAMILIES”—ENEMIES BY NATURE
MADE FRIENDS BY ART.
ne of the most entertaining and popular features of Barnum’s
Museum, during the many years of its existence, was that
miscellaneous collection of minor birds, beasts, and reptiles,
denominated the Happy Family. Here in a huge cage are mingled
many varieties of the animal kingdom which are, in a state of nature,
deadly enemies to one another. Exhibitions of this kind are very rare
in this country, though more common in Europe. Probably the first
one ever seen here was that imported by Barnum in 1847, and which
was the foundation of the present collection; though, like the boy’s
jack-knife which first had a new blade and then a new handle, and
then a new blade again, it would be difficult to find any of the
original importation in the collection of the present day. It seems
that Barnum, at about the date we have mentioned, was in Scotland
“working” Tom Thumb, who was then on a grand exhibition tour. In
the neighborhood of Edinburgh he accidentally stumbled across the
Happy Family, which was then, though an excellent collection of
animals, a rather one-horse affair as an exhibition by itself. The
shrewd showman, ever on the lookout for novelties or curiosities,
genuine or otherwise, fancied he saw a good speculation and bought
the whole concern for $2,500, and brought it in triumph to his
museum in New York.

THE “HAPPY FAMILY”
AT BARNUM’S OLD
MUSEUM.
Curious and wonderful as this peaceable living together of animals
of such diverse natures appears, there is really very little mystery in
it. Many persons, noticing the sleepy and listless appearance of most
of the animals, have quite naturally come to the conclusion that they
were under the influence of some drug, which stupified them and
rendered them harmless. We believe that in no case is this the fact,
because it is not necessary. The main secret is to feed the animals to
satiety; never allowing them to feel the pangs of hunger, the great
incentive for preying upon other animals is taken away. Animals,
unlike men, will never eat unless they are really hungry. We have
frequently observed boa constrictors at public exhibitions, in whose
cages rabbits or pigeons had been placed to gratify the public with
the sight of the huge snake swallowing his food alive. Unless the
snake is hungry the miserable little victims remain for days cooped
up with the hideous monsters without the latter taking the slightest
notice of them. It is a well known fact that cats which are fed
plentifully cease to be good mousers, however excellent in that
respect they have previously been, and will permit a house to be
overrun with these pests without molesting them. Besides the
plentiful feeding there is one other thing requisite to make the
animals live together peaceably. Many animals have an instinctive
desire to worry or kill others which are smaller or weaker than
themselves. Between many particular animals a kind of natural
antipathy exists. So natural does it seem that a dog should torment a
cat that “a cat and dog life” has become typical of a very
uncomfortable state of existence. There is on the part of all animals a

feeling of suspicion and antagonism toward strange animals, even if
they are of their own species. We are almost every day witnesses of
exhibitions on a smaller scale almost as wonderful as the Happy
Family, were it not that their frequency renders them common place.
In thousands of households cats and dogs live together, not only
without quarreling but on really friendly terms. Frequently have we
seen cats and dogs feeding from the same dish, and recollect one
instance where a diminutive kitten, in the innocence of feline
infancy, seized upon one end of a bone which a monstrous watch dog
was busily gnawing, without being molested by the dog. It is just as
natural for cats to devour birds as for any beast or bird of prey to
devour its victims, and yet we have been familiar with more than one
instance of canary birds being allowed to fly around a room in which
was the household cat, without the cat showing the least disposition
to attack them. Had a strange bird came within her reach we doubt
not that same cat would have indulged in a feast at his expense
without hesitation. City dogs would make sad havoc among the
inhabitants of any poultry yard if allowed admission therein, but let
any one of those same dogs become a resident on a farm, let him
understand that chickens and turkeys are sacred from his touch and
he will soon walk among them as unconsciously as though there were
no such things in existence. An instance is on record of a cat who had
been deprived of her kittens, capturing a brood of young rats and
suckling them with all the tenderness of a mother. In this case,
however, it would appear that affection for the baby rats was not the
motive for this strange act, for as soon as the cat was eased of the
inconvenience of her milk, she disposed of her adopted family in a
pleasant and effective manner—she ate them up.
In preparing animals for Happy Families it is usual to keep them
in small cages, in the vicinity of each other. Occasionally two animals
of different dispositions are placed together, the keeper preventing
any fighting and punishing any symptoms of it. When the keeper
thinks they may be safely left together he retires to a short distance
to wait results. On the least sign of a quarrel he is down upon them,
poking and punching and stirring them up generally. If they show no
disposition to quarrel they are treated kindly, fed plentifully and
permitted to enjoy themselves as much as their restricted quarters
will permit. When an animal has thus learned to keep within the
bounds of politeness and good breeding he is introduced into the

large cage with the grand collection. In this large cage the principal
disturbing elements are the monkeys, who frequently obstinately
insist upon not being happy, and slinging the mice around by their
tails, pulling out the birds’ feathers and other little acts of
playfulness. The stout wire very soon reduces them to quietness, and
it very seldom happens that any serious disturbance occurs. Doves
and vultures roost calmly side by side, mice nestle confidingly in the
cat’s soft, warm fur, and so natural does it all seem, that, for a
moment one scarcely realizes of what incongruous elements the
whole is made up.
The origin of this novel idea of the Happy Family was probably
this: Francesco Michelo was the only son of a carpenter who resided
in Tempio, a town in the island of Sardinia. He had two sisters
younger than himself, and he had only attained his tenth year when a
fire reduced his father’s house to ruins, and at the same time caused
the death of the carpenter himself. The family were thus reduced to
beggary, and the boy in order to provide for the necessities of his
mother and sisters took up the occupation of catching birds for sale.
Constructing a cage of considerable dimensions from laths he
proceeded to the woods to secure the nests of young birds. Being
active and industrious he succeeded tolerably well, but the prices he
obtained were not adequate to the maintenance of the family. In this
dilemma the boy conceived a new and original method for increasing
his income; necessity is the mother of invention, and he meditated
no less a project than to train a young Angora cat to live harmlessly
in the midst of his favorite songsters. Such is the force of habit, such
the power of education, that by slow degrees he taught the martial
enemy of his winged pets to live, to eat, to drink, and to sleep in the
midst of his little charges without once attempting to devour or
injure them. The cat, whom he called Bianca, suffered the little birds
to play all manner of tricks with her; and never did she extend her
talons or harm them in any way.
He went even farther, and taught the cat and the birds to play a
kind of game, in which each had to learn its own part. Puss was
instructed to curl herself into a circle, with her head between her
paws, as though asleep. The cage was then opened and the birds
rushed out upon her and endeavored to awaken her with repeated
strokes of their beaks; then dividing into two parties they attacked

her head and her whiskers, without the gentle animal appearing to
take the least notice of their gambols. At other times she would seat
herself in the middle of the cage, and begin to smooth her fur; the
birds would then settle upon her back, or sit like a crown upon her
head, chirruping and singing as if in all the security of a shady wood.
The sight of a sleek and beautiful cat seated calmly in the midst of
a cage of birds was so new and unexpected that when Francesco
produced them at the fair of Sussari he was surrounded instantly by
a crowd of admiring spectators. Their astonishment scarcely knew
bounds when they heard him call each feathered favorite by its name,
and saw it fly toward him with alacrity, till all were perched on his
head, his arms, and his fingers. Delighted with his ingenuity the
spectators rewarded him liberally, and the boy returned joyfully to
his home with sufficient money to last the family many months.
Not only do animals sometimes lose many of their natural
characteristics by association with human beings or with other
animals, but they even in some cases have been known to acquire the
habits of animals of an entirely different species from themselves.
One of the most remarkable instances of this was observed by La
Malle. This gentleman had a kitten which had attained the age of six
months when his live stock was increased by the arrival of a terrier
pup, Fox, that was only two months old. The dog and the cat were
brought up together, and for two years Fox had no association with
other dogs, but received all his education from the three daughters of
the porter, and from the cat. The two animals were continually
together and acquired a great affection for one another; the cat,
however, as the senior taking the lead. Soon Fox began to bound like
a cat, and to roll a mouse or a ball with his fore paws after the feline
fashion. He also licked his paw and rubbed it over his ear as he saw
the cat do; nevertheless, owing to his native instinct, if a strange cat
came into the garden he chased it away. La Malle brought a strange
dog into the house, who manifested the utmost contempt and
indignation for all Fox’s habits. M. Andouin, too, had a dog which
acquired all the habits of a cat.
It has probably been remarked also, by most readers, that
domestic animals almost always imbibe something of the disposition
of their masters or mistresses. Thus, a plodding easygoing man will
have a horse of much the same characteristics if it has been long in

his service, whatever may have been the horse’s original disposition.
Many similar instances will no doubt suggest themselves to the
reader. It would seem that even mankind is not exempt from this
influence, and that when men have not the energy or mental force to
exert this molding power over the minds of their brute companions,
the animals will exert it over them. At the risk of wandering from our
subject it may interest some to have attention called to the testimony
to this assertion, afforded by all uncivilized countries. Dr. Virey, who
has given considerable attention to this rather queer subject,
remarks: “Behold those men who pass their lives among animals, as
cowherds, shepherds, swineherds, grooms, and poachers, they
always acquire something of the nature of the animals with which
they associate. It is thus that man becomes heavy and rude with the
ox, filthy and a glutton with the pig, simple with the sheep,
courageous and an adept hunter with the dog. In like manner the
Arab is sober with his camel, the Tartar rough and blunt as his
horses, the Laplander timid as his reindeer, the mountaineer active
as the goat, the Hindoo somber as his elephant, because it is man’s
fate to take the nature of his animals when he cannot form their
nature to his.” Without recommending the adoption of this writer’s
opinions entirely, for much that he has stated is no doubt due to
climate and local causes, his theory is worthy of consideration by
those who have a fancy for this kind of speculation.
A correspondent of the Agriculturist relates an amusing instance of
a sort of “happy family” originated by the animals themselves:
“About a month since two cats had a ‘family’ within a few days of
each other. All the kittens were drowned except two of each set,
which with their respective mammas were snugly settled in a couple
of boxes in the same room. On the following day both families entire
—or rather what remained of them—were found coiled up together in
the same box. They were not disturbed and thenceforward the two
mothers ceased to recognize any difference between the two pairs of
kittens. They would alternately nurse the whole lot, or both
affectionately entwined together divide this ‘labor of love’ just as the
kittens, lying snugly between them, would happen to turn to the one
or the other. But this is not all. Eddie brought a couple of young
squirrels from the woods, which soon became very gentle. In less
than two days both were found in the box among the cats and kittens,
drawing from either or both the maternal fonts, upon a like footing

of equality and community with that previously enjoyed by the
kittens. The old cats seemed to acquiesce fully in the arrangement,
and so it proceeded for a couple of weeks, until one of the squirrels
was accidentally killed. The other having the freedom of the house is
now a romping playmate of both cats and kittens, who continue
uniformly to treat him as ‘one of the family.’”

A
CHAPTER XX.
EDUCATED SEALS—TAME FISH, ETC.
t the Zoological Gardens in London, and at several places on the
continent, seals have been exhibited which had been taught to
perform a number of tricks. The first “learned seal” which appeared
in this country was one exhibited first at Barnum’s old Museum, on
the corner of Broadway and Ann street, and afterward in various
parts of the country. Ned, as he was called, was quite a philosopher
in his way, and submitted gracefully to the change from his secluded
haunts on the icy shores of Greenland, to the excitements of a public
life.
Seals are naturally docile and intelligent, but skill in grinding a
hand organ is scarcely a gift which comes by nature, and even in the
case of Ned it was necessary to stimulate his musical taste before he
became an adept on that instrument. This stimulus was the same as
that to which we owe the curb-stone performances of modern
Romans—hunger.
He had before this learned of his own accord to come up out of the
water on the appearance of his keeper. He was kept in a large tank,
or box, one half of which held the water, while the other half was
floored over forming a platform on which he was exhibited. From
this platform an inclined plane, formed of planks, led down into the
water. Around the edge of the tank and platform a wooden railing
extended, and in one corner of this enclosure was kept a tin box
containing the fish with which the seal was fed. When the seal was
first exhibited his keeper was in the habit of taking a fish from this
box at each half-hourly exhibition, and tossing it to the seal who
would come partly out of the water and open his mouth to catch it
when he saw it in the keeper’s hand. This box had a lid to prevent
Ned helping himself, and the seal soon learned that the noise of

opening the box was followed by his getting a fish; so before long it
was only necessary to tap on the lid to make him come up on the
platform.
There was one trick which Ned invented himself, and used to
perform to his own great satisfaction. He always liked to be able to
see his keeper, but visitors often crowded around the tank so much
as to obstruct his view. When this happened, Ned had a way of
beating vigorously about in the water and splashing the offending
spectators so that they were glad to withdraw to a more respectful
distance. This afforded considerable fun to the attachés of the
museum, who had discovered Ned’s little game, while, we believe,
visitors never suspected that their ducking was anything more than
mere accident.
The first feat he was taught was to sit up on his hind quarters. This
was easily accomplished by holding a fish in the air as an
encouragement for the seal to keep an erect position. More difficulty
was experienced in teaching him to play the organ. Day after day his
paw was placed on the handle, while the trainer industriously turned
the crank and held Ned’s paw in position at the same time. Ever and
anon the man would remove his hand to see if the seal continued the
motion, but down would flop Ned’s paw and he would gaze vacantly
at the instrument without the least apparent consciousness of what
was to be done. But by-and-by there was a little hesitation in the paw
and it did not drop quite so promptly on the trainer’s hand being
removed. Then Ned got a little fish. The next time the paw lingered
quite perceptibly on the handle, and there was just the faintest
movement toward turning the crank. Then Ned got a bigger fish,
which he undoubtedly relished exceedingly, for all this time he had
been on short allowance. So it went on, the seal grinding a few notes,
increasing their number each time and being rewarded with fish,
until he had learned to roll out the full supply of tunes the
instrument afforded, though his “time” would have puzzled a
musician, his efforts being to grind at the greatest possible speed,
and we feel safe in asserting that his “Old Hundred” was the fastest
thing on record. After every exhibition he was rewarded with fish.

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