'S^^ :■■.■■■■■
L on mans'
Object Lessons
D, SALMON
I
BOUGHT WITH THE INCOME
.FROM THE
SAGE ENDOWMENT FUND
THE GIFT OF
Henrg W. Sage
1891
..A,3.311-Q- - - slU^Iis
Cornell University Library
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Longmans' object lessons
3 1924 031 295 938
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Library
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OBJECT LESSONS
WORKS BY DAVID SALMON.
LONGMANS' SCHOOL GRAMMAR. Written to meet
the requirements nf Pupil TcactKTS, of the Oxford aud Cam-
bridge Local Examinations, the Examinations of the College .1 •!.
of Preceptors, &c. Orown 8vo 2 6
Part I. Parts of Speech.
Part II. Classification and Inflection.
Part III. Analysis of Sentences.
Part IV. History and Derivation, and Notes for Teachers.
LONGMANS' JUNIOR SCHOOL GRAMMAR. Fcp.
8vo. 128 pp 10
Part I. Parts of Speech.
Part II. Parsing.
LONGMANS' JUNIOR SCHOOL COMPOSITION.
Fcp. 8vo 10
This Book contains :— Synthesis of Simple Sentences ; Practice
in the Synthesis of Simple Sentences ; Sentences combined ;
Pmictuation.
Easy Narratives : (a) Stories to be reproduced.
(b) Skeletons of Stories to be reproduced.
(c ) Stories in verse to be written in prose.
Easy Essays : Letters ; Gi-rammar (Typical Errors) ; Notes for
Teachers, &c.
LONGMANS' SCHOOL COMPOSITION. downSvo. 2
SIR ROGER DE COVERLEY : Essays from Ibe
'Spectator.' With Notes and Illnatratious. Crown 8vo. .. 1 G
London; LONGMANS, GREEN, & OO.
LONGMANS'
Object Lessons
HINTS ON PREPARING AND GIVING THEM
WITH FULL NOTES OF
COMPLETE COURSES OF LESSONS
ON
ELEMENTARY SCIENCE
BY
DAVID SALMON
AUTHOR OF
' LONGMANS' SCHOOL GRAMMAR ' AND 'SCHOOL COMPOSITION
LONDON
LONGMANS, GREEN, AND CO.
AND NEW YORK : 15 EAST 16* STREET
1891
[A// rights reservcd\
/ CORNELL N
lUNlVERSITYJ
W LIBRARY/
Dans les premieres operations de I'esprit que les
sens soient tons ses guides. Point d'autre livre que le
monde, point d'autre instruction que les fails. L'enfant
qui lit ne pense pas, il ne fait que lire ; il ne s'instruit
pas, il aj^prend des mots. — ROUSSEAU : Etftile
CONTENTS
PART I.
HINTS ON PREPARING AND GIVING LESSONS
PAGE
PAGE
Should Science be Taught?
I
Language
27
When should Science Teachin^
y
Questions
29
Begin? ....
6
Telling and Eliciting
34
Subjects of Lessons .
8
EiHpIiasis ....
36
Matter of Lessons
II
Suntinary
37
Notes of Lessons
15
Recapitulation .
38
Illustrations
17
PART II.
NOTES OF LESSONS
FIRST YEAR.
A. LESSONS ON COMMON PROPERTIES.
Solvents and Solutions .
41
Plastic Substances
• ■ 49
Crystals. SaU-?naking
43
Bricks . . . .
• 50
Suspension. Porosity .
44
Rlasticity .
■ • 51
Filters ....
46
Lndiarttbber
• • 53
Sugar ....
47
VI
Longviafis' Object Lessons
B. LESSONS ON COMMON ANIMALS.
TJie Cat
The Dog
The Horse
The CoiV
The Ass
55
56
5S
60
62
The Sheep .
The Pig
The J/oies£
The Hen
The Duck
63
64
65
66
6S
C. LESSONS ON PLANTS,
Com ..... 69
Rice 71
Maize 72
Some edible Roots . ■ ■ 73
Some edible Vci^etables . . 74
CoiOa
Coffee . . .
Oi-anges and Lemons
JMustard
Tlic Oak .
75
77
7S
79
So
SECOND YEAR.
A. LESSONS OX COMMON PROPERTIES.
Ha!\( and Soft Substances
Si
Copper ....
$9
Fiisio7i ....
82
Tin
90
Ductility, Tenacity, Malle
Zinc ....
91
ability ....
S3
Pins
92
Iron ....
S6
Pens ....
93
Lead .....
87
B. LESSONS
ON ANIMALS.
The Lion and the Ti^^er .
94
T/te Rabbit
lOS
Tlie Wolf and the Jackal .
96
The Beaver .
107
The Elephant
98
The Swallow
no
The Camel
100
The Ostrich .
IIS
The Beat
102
The Herring
• "5
Flax
Cotton
Cork
C. LESSONS ON PLANTS.
. 116 Leaves
. . 117 I Tea
. 119 Tobacco _ .
120
128
129
Contents
Vll
THIRD YEAR.
A. LESSONS ON ELEMENTARY CHEMISTRY AND PHYSICS.
Oxygen .
Nitrogen .
Carbonic Acid Gas.
Hydrogen .
A Burninc: Candle
■ 131
Matches
• 135
Coal Gas
• 136
Ventilation
. 1 38
Winds .
■ 139
Rain and Snow
PAGE
140
142
146
LESSONS ON REPTILES AND INVERTEBRATA.
T/ie Fj'og
149
The Housefly
TJie Ci-ocodile
151
The Ant
Snakes
154
The Spider
The Butterfly .
157
The Snail
The Bee ...
159
The Earthworm
C. LESS
ONS
ON FLOWERS.
Tlie Wallflower ' .
169
Tlie Daffodil
The Primrose .
171
The Garden Pea
The Buttercup
172
The Daisy
The Dead Nettle
174
Tlie Dandelion
The Tttlip . . . .
175
Comparison
161
162
163
165
167
175
176
177
178
178
FOURTH YEAR.
A. LESSONS ON ELEMENTARY PHYSICS.
Solids, Liquids, and Gases . 181
Effects of Heat . . . . 182
Pressure of Liquids . .186
Pressure of the Air . . . 189
The Pump
Equilibrittm of Liq^iids
Capillary Attraction
Magnets .
B. GENERAL LESSONS ON NATURAL HISTORY,
Mammals
The Whale
The Bat
Birds
205
206
208
211
Reptiles
Insects .
Teeth
Coverings
■ 194
. 198
. 202
• 203
215
216
219
222
Fishes 214
viii Longmans' Object Lessons
C. LESSONS ON ELEMENTARY BOTANY.
PAGE PAGE
Cotyledons .... 223
Roots 225
Stems 228
Leaves . . . . . 232
Flowers and Fertilisation . 233
Fruit and Seed . . . . 237
Flowerless Plants . . . 240
APPENDIX
SCHEMES OF OBJECT AND SCIENCE LESSONS
A. The School Board for London.
Instructions to Teachers on Object Lessons and Elejnentary
Science .......... 242
A Scheme of Object Lessons and Science Teaching for Standards
I. to VII. 248
B. Report of the Committee of the American Society of
Naturalists on Science in the Schools . . . 258
C. Middletown, Connecticut.
Course of Science Teaching in the Pnblic Schools . . . . 261
D. English Education Department.
Elementary Science Courses ....... 267
NOTES OF A LESSON ON THE CAT 275
INDEX. . . . ■ 277
LONGMANS'
OBJECT LESSONS
PART I
HINTS ON PREPARING AND GIVING
LESSONS
SHOULD SCIENCE BE TAUGHT?
Students of education who are engaged in the actual work
of instruction are frequently forced to think how, but rarely
„ . , ^ why, any given subject should be taught. Every
tions which teacher must himself answer the first question ; the
should in-
fluence the second is generally answered for him. Authority or
subjects of custom decides that certain subjects shall be taught
instruction. ^^^ ^^izx certain other subjects shall not be taught :
hence there is no room for choice except among that class
of subjects concerning which authority is silent and custom
speaks with varying voice. That class at present often in-
cludes science, and before we can decide whether science
should be taught, we must examine the principles that ought
to determine the admission of any subject into a well-con-
sidered course of studies.
The first principle is practical value. School life is a pre-
B
2 Longmans^ Object Lessons
paration for the wider life to follow, and it is the duty of a
teacher to provide his pupils, as far as possible, with the know-
ledge which they will require after they have passed from
under his care. If, for instance, they were all going
' "^' to be physicians, it would be his duty to give them
as much instruction in anatomy, physiology, chemistry, and
materia medica as they had time and capacity to receive. The
same remark applies to every other calling. But, as a rule, the
teacher does not know what are the occupations before his
pupils, while he does know that these occupations are many
and diverse, and that he has no time to teach even the rudi-
ments of any of them. It, therefore, is his duty to prepare
children, not for one trade or profession, but for all ; it is his
duty not to make them doctors or lawyers, shopkeepers or
artisans, but to make them men and women with faculties
well developed and minds well stored with information that
cannot fail to be of service in any walk of life. His aim must
be the greatest usefulness to the greatest number. Conse-
quently those subjects ought most frequently to appear in
courses of study, a knowledge of which is most frequently
required in practical affairs. Reading, writing, and arithmetic
are taught to every pupil in every school, because every pupil
after leaving school finds a knowledge of them essential.
The second principle that ought to regulate the admission
of any subject into a course of study is educative value. The
2. Educa- muscles grow and are strengthened by use, and as
tive value, work and the ordinary activities of life are hkely to
produce a disproportioned and partial development of the
body by unduly exercising some of the muscles while leaving
others unexercised, gymnastics have been invented. Now, the
fact that most men go through life without being called upon
to exhibit acrobatic skill is no argument against gymnastics.
We practise them not because we think that some day we may
Should Science be Taught? 3
be called upon to swing on a trapeze, vault over parallel bars,
or handle dumb-bells and Indian clubs, but because we know
that they make the body fitter for the performance of what-
ever operations it may be required to undertake. What is true
of the body is also true of the mind. The mental faculties
grow and are strengthened by exercise, and we pursue certain
studies not because we think we shall be called upon to apply
them, but because we know that they make the mind fitter for
the performance of whatever operation it may be required to
undertake. Algebra and Euclid are cases in point. No one
who knows these subjects would deny that they have immense
practical value, but we do not teach them solely, or indeed
mainly, because of that. Though we might be quite sure that
none of our pupils would ever apply his knowledge of algebra
or of Euclid, we should continue to teach both for the sake
of the mental development that the study of them brings.
Algebra trains the mind to deal with abstractions and generali-
sations, and Euclid to make correct deductions from stated
premises, and though skill in mathematics may to many per-
sons be of little practical value, skill in abstract and deductive
reasoning must be of great importance to everyone.
The third principle that ought to regulate the admission of
a subject into a course of study is aesthetic enjoyment. Litera-
ture and art are taught not so much because of their
3. Pleasure. . ,
practical or educative value, as because they tend to
refine and elevate the mind and add largely to the innocent
pleasures of life.
Applying to a particular case the three general principles
thus laid down, what are the claims of science to a place in
^. , ■ every school curriculum ? If based on only one of
of science, f^g three, its claim deserves consideration ; if based
" ^' on two, it is very strong ; and if on the three, it is
irresistible. The utility of science is now universally admitted.
B 2
4 Longmans' Object Lessons
Science helps to satisfy the first and strongest demand of
nature — the demand for self-preservation. Increased knowledge
of the laws of sanitation, with increased obedience to them, has
in the last half-century added ten years to the average length
of human life, and has, at the same time, made life more
enjoyable and more useful because more healthy. And the
limit of improvement is far from being reached yet. Thousands
of babies still die annually from their mothers' ignorance of
infant digestion and the constituents of food, and thousands
of men and women contract avoidable diseases from ignorance
of hygienic laws. Besides preserving health and prolonging life
science adds to our comforts and conveniences. Steam and
electricity are only two of the forces that it has enlisted in our
service, and yet, deprived of these two, existence to the modern
man would hardly seem worth having. Science is, moreover,
the foundation of every art and manufacture carried on among
civilised people. If, therefore, any subject can claim to be
taught in schools because of its utility, surely science can.
The claim of science to be taught for the purpose of
developing the faculties is also incontrovertible. Every physical
2. Educa- science begins with the careful and intelligent ob-
tive value, servation of facts and then proceeds to classify and
generalise ; hence the pursuit of it gives a keenness to the
senses and a vigour to the reasoning powers which must be of
immense value in any department of human activity. Each
faculty trained by the study of science may perhaps be trained
by the study of some other subject, but no other subject trains
at once all the faculties trained by science.
The study of science also adds to the plea.sures of life.
Where another person might see only a dull flat country and
3. Plea- ^ soil as void of interest as of crops, one who knows
'"■■<=■ something of botany and zoology sees open before
him a fascinating page in the great book of nature. Every
Should Science be Taught? 5
blade of grass, every tuft of moss, the butterfly that crosses
his path, the lark that mounts aloft, is for him instinct with
meaning and delight. A starry sky is to everyone a beautiful
picture. To the astronomer it is that and much more. Every
brilliant point is to him as the face of an old friend ; he knows
its name and its history, and looks for its return at the appointed
time. And so with every other science. We cannot study
one which shall not add interest to every country walk, to
every excursion on river, lake, or sea, even to every journey by
rail. It was the loss of innocent pleasure, not of useful
information, that Carlyle deplored when he said : ' For many
years it has been one of my most constant regrets that no
schoolmaster of mine had a knowledge of natural history, so
far at least as to have taught me the grasses that grow by the
wayside, and the little winged and wingless neighbours that are
continually meeting me with a salutation which I cannot answer
as things are. Why did not somebody teach me the constel-
lations, too, and make me at home in the starry heavens which
are always overhead, and which I don't half know to this day ? '
In our time the most powerful and the most uncompromising
advocate of the study of science is Mr. Herbert Spencer, but
he has somewhat weakened his own case by over-
Mr, ^
Herbert Stating it. He argues or takes for granted that the
greater part of school time should be devoted to
science ; that every pupil should master every science which
is applied to practical purposes ; and that the chief end of
education is the acquisition of useful information. Most of
those who have examined the principles of pedagogy will agree
v?ith Mr. Spencer that science should have a place — should
have a large place — in every curriculum, but this does not
commit them to accepting all his contentions or assumptions.
Except when it is the business of our lives to apply some
science practically, we study it in order that our faculties may
6 Longmans^ Object Lessons
be developed, and that we may be able to take an intelligent
interest in the world around us. Utility is only one, and not
necessarily the first consideration ; hence it would not be wise,
even were it possible, to master every -ologyK Surely Mr.
Spencer is wrong in thinking that science, long the Cinderella
of the schools, should henceforth queen it over her elder
sisters, literature and art ; and those are equally wrong who
think that she should be driven back to her old station in the
kitchen.
WHEN SHOULD SCIENCE TEACHING
BEGIN?
As.suMiNG that science is to be taught to all, when should the
teaching begin ? What has already been said about the edu-
y^m cative value of the subject points to the answer. The
chUdren study promotes the growth and vigour of the facul-
capabie of ties employed in observation, classification, gene-
the formal
study of ralisation, and inductive reasonmg ; but of these
only the faculties employed in observation are active
in young children, the others being either dormant or altogether
absent. It is therefore obvious that a complete and rigid study
of science is beyond the capacity of young children, and that
such study should begin only when the powers of abstract
thought are sufficiently developed. This they are believed to
be in ordinary cases at the age of twelve to fourteen, and to
attempt the teaching of severe science before that age has been
reached is to don the armour of Saul on the body of David.
But it does not necessarily follow that no scientific teaching
should be given before. It is true that all the requisite facul-
ties are not present in young children ; but those that are
present should be trained from the first, and the training of the
When should Science Tcachiuir besrin ?
<5
rest should begin as soon as they manifest themselves. The
very baby in arms begins to observe. As soon as he has attained
to speech, he is full of questions about the objects
ceptive around him and the phenomena of daily life. If
are mani- his natural curiosity is wisely satisfied and directed,
smd^diou/d ^ broad and deep foundation is already laid for
be trained future scientific teaching ; but, should his curiosity
early.
be suppressed or left without guidance, the absence
of a body of sound observation to form a basis for scientific
teaching is only one, and that not the greatest, of the resulting
evils. A greater evil is the undeveloped state of the perceptive
faculties themselves. A professor of geology in one of the
American Universities says : ' I feel daily that the efficiency of
my work as a student and teacher of science is marred by the
vice of early education, which repressed rather than developed
whatever powers of observation nature had given. My profes-
sional life has been a perpetual struggle to rid myself of some
of the mental habitudes induced by an unnatural education.
. . . And what I have felt in myself I have seen in my students.
It is worse than making bricks without straw to teach natural
science to college juniors and seniors in whom disuse has
wrought so complete an atrophy of the powers of observation
that they hardly know that there is an external universe.'
This, then, is the answer to the question, 'At what age
should the teaching of science begin?' The complete and
formal teaching of any science can begin only when
When
should the powers of abstract thought have begun to manife.st
teaching themselves — that is, only when the child has reached
beg'n? jj^g g^gg of twelve to fourteen ; but teaching calcu-
lated to develop the faculties required for the study of science
must begin even in the infant school. If there were no other
argument in favour of beginning thus early, there is an incon-
trovertible argument in the fact that the school education of
8 Longmans' Object Lessons
the majority of our children ends before the time for the
definite study of science has arrived, and that if they are not
trained in the infant school and the lower classes of the primary
school to perceive physical truths, and, in a measure, to reason
from what they perceive, they will be forced to go through life
without the help of intellectual implements and tools that
might have been theirs.
Courses of Object Lessons, arranged with some regard to
the laws of psychology, prepared with care and given with skill,
Object by directing the attention of children towards tan-
Lessons a gii-,ie things, by encouraging them first to observe,
substitute ° & ! J b &
and pre- then to compare, and finally to classify and general-
paration , . . , _ .
for science ise, fumish, not indeed an equivalent for definite
mg. g|,jence teaching, but the best substitute possible in
the case of those who leave school at an early age. Such Ob-
ject Lessons are, moreover, the best preparation for it, because
they place the pupil in the right road and lead him some way
along it. AVhen he begins the study of science he has simply
to go further and faster in the same direction — he has simply
to make more minute observations, more comprehensive com-
parisons, more distinct classifications, and more sweeping
generalisations.
SUBJECTS OF LESSONS
In the planning of courses and in the preparation ot the
Principles lessons themselves two principles must be kept
underlying t, •
courses. Steadily in view : —
I. The end to be aimed at must be clearly understood,
and the courses so arranged that they shall lead up to that
end.
Subjects of Lessons
2. The lessons must be adapted to the successive stages
of mental growth through which the children pass.
airaed'at'''' The ends to be aimed at are three :—
1. The cultivation of the perceptive powers.
2. The communication of useful knowledge.
3. The cultivation of the powers of generalisation and of
inductive reasoning.
With the youngest children the first must be the end chiefly
aimed at, with the eldest the third. The second should be
kept in view in all the lessons, but should not be allowed to
dominate any.
The earliest lessons should be on the common objects and
the common animals to be seen in the home, the school, the
Subjects streets, and the fields. The children should be made
siiouid be '^y ^^ "^^ '^'^ \hiiyc own senses, aided by judicious
chosen. questions from the teacher, to perceive the forms
and chief properties of the objects and the most striking cha-
racteristics of the animals. A little later there should be
lessons on common natural phenomena, such as clouds, mist,
rain, snow, and thunder. Gradually the range of observation
should be extended till it includes typical selections from the
animal, the vegetable, and the mineral worlds, and the simplest
elements of physics and biology. Finally, Object Lessons
should give way to definite lessons on those sciences towards
which all the courses have been gradually tending.
Having regard to the fact that the powers of children are
constantly developing, it is obvious that several lessons may be
given on the same subject at successive stages. Three lessons
may, for example, be given on coal, the first dealing with its
more obvious properties, the second with the mining, and the
third with the origin of it.
In looking over actual courses of Object Lessons one is often
lo Longmans' Object Lessons
struck by the fact that they include lessons which must be
given without any appeal to the senses, and which, therefore,
Subjects cannot, properly speaking, be Object Lessons at
should not ^'1- I have seen ' included lessons on Miltiades,
be chosen. Alexander the Great, Hannibal, and Julius Csssar ;
on Martin Luther, Mohammed, Frederick the Great, and
Napoleon ; on Scott's Novels and Shakespeare's Plays ; on
Drake, Cook, Franklin, and Livingstone ; on Arctic and jn
African Exploration ; on Honesty, Truthfulness, Temperance,
and Kindness ; on Thrift, Wages, Strikes, Supply and Demand,
Money, Rent, Taxes, Trial by Jury, and the Making of
Laws. No one will deny the extreme desirability of giving
lessons on most of these subjects ; all that I contend for
is that they should not be included in a course of Object
Lessons.
Granted that every subject chosen may rightly be
mem"or included, the arrangement of the subjects into series
lessons in remains. The three chief points to be considered
courses. ^
here are : —
I. That each lesson shall be placed in that part of the
series where it shall be most suited to the stage of mental
development reached by the class. An observation lesson on
the properties of chalk, for example, would be too simple for
children of eleven or twelve, while one on the composition and
origin of chalk would be too difficult for children of seven or
eight. The first would convey no information because most
of the facts would be familiar, and the second would convey
little because most of them would be unintelligible. The first
would make no demands, and the second would make impos-
sible demands upon the powers of the children ; neither,
1 I hope that the fact of its having been my duty to hear and criticise the
lessons of hundreds of teachers will be allowed to excuse occasional reference
to what has come under my own notice.
Subjects of Lessons 1 1
therefore, would interest or instruct ; neither would possess
any value, practical or educative.
2. That the lessons shall follow one another in logical
order and coherence. All the information that is necessary to
a complete understanding of the second should be given in the
first ; of the third in the first and second. A lesson on the
composition of air, for example, should follow, not precede,
lessons on the constituent gases.
3. That the lessons shall lead directly to the end proposed.
It has already been shown that Object Lessons form the best
preparation for definite science teaching, and both in the choice
and the arrangement of the subjects the particular science or
sciences to be taught ought always to be kept in view.
MATTER OF LESSONS
The subject of the lesson being decided upon, the teacher
Matter of has next to decide what he shall say about it. It
should var would be as impossible to teach as it would be
with unwise to try to teach all the facts available, and a
selection has to be made varying with —
(i) The age of children,
(2) What they already know of the subject,
(3) The time allotted to the lesson.
I. If the children are young, the teacher will dwell chiefly
upon the simple facts which they can find out by the exercise
I Ao-e of of their senses and the simple inferences which they
children, ^^^^ i^g igd to make, while he will avoid technical
terms, difficult generalisations, and complicated explanations.
If, for instance, a lesson were to be given to children of seven
or eight on the parts of a flower, the teacher would show the
parts in different specimens till the children could recognise
12 Longmans' Object Lessons
them under their varying forms, but he would say nothing of
the functions of the parts or of their botanical names. On the
other hand, if a lesson on the same subject were given to chil-
dren of eleven or twelve, great stress would be laid on the
functions, and the botanical names would be introduced.
Similarly, if the lesson were on a manufacture, the teacher
would with the younger children demonstrate the essential
qualities of the raw material, and give only the broadest outline
of the successive processes ; whereas with the elder children he
would almost assume an acquaintance with the qualities, and
give pretty full details of the processes.
2. If what the children have already learned is not taken
^, . into account in the choice of matter, their time may
2. Their -'
previous be wasted in an attempt to teach them what they
know, or the foundations laid in previous lessons
may be ignored, and the old instruction may not be made to
serve as a basis for the new.
3. When the teacher in preparing a lesson does not bear in
mind the number of minutes at his disposal he may provide
3 Lensjth ^'^^ Y\Vi\e. matter or too much. If there is too little,
of lesson. ]^g jg likely to use vain repetitions in order to occupy
the allotted period. If, on the other hand, there is too much,
he is likely to hurry through it, teaching nothing effectively, or
to teach the first part effectively and to omit the last part alto-
gether. In the first case the lesson is vague, in the second
unsymmetrical ; in either case no foundations are laid for the
next lesson in the series.
With regard to the choice of matter a word of caution may,
perhaps, be necessary. An Object Lesson is a lesson on objects,
Things, not ^ot on language. Incidentally and indirectly it may
words. teach new words or give clearer notions of the
meanings of old ones, but when it is deliberately made the
medium of instruction in language its purpose is entirely mis-
Matter of Lessons 13
understood. Perhaps the greatest and most common mistake
in this respect is unintentional. I have heard a teacher who
had to give a lesson on Leather, and who fully believed that he
was doing all that could be expected of him, spend more than
half his time, not in trying to show that the substance is
odorous, flexible, opaque, cScc, but in trying to explain the
terms odoroi^s, flexible, opaque, &c. A satisfactory lesson might
be given on the Properties of Leather by first demonstrating how
many of them are found in the original hide and how many are
imparted in the manufacture, and then by explaining how the
various uses of leather depend upon the possession of them ;
but that would be a lesson on the properties, not on the
meaning of certain hard words employed to denote them.
The next step after the selection of the matter is the
arrangement of it ; but here no very definite directions can be
given, because an arrangement which is bad in one
Arrange-
ment of set of circumstances may be defensible in another.
To begin a first lesson on the Cat, for example, by
saying that the animal belongs to the sub-kingdom vertebrata,
to the class mammalia, the order carnivora, and the family
felidffi would betray gross lack of judgment and gross ignorance
or disregard of psychology, whereas to begin thus might be
justifiable after a large number of lessons had been given on
typical animals and on the principles of classification.
I. The first general direction with regard to arrangement
is that the facts should be presented in a natural order. The
I Should teacher should consider what are the processes by
be natural, ^yhjch children, if left to themselves, acquire know-
ledge, and he should imitate those processes as far as may be
consistent with obtaining more definite results in a briefer
period. If, for instance, a lesson had to be given on Lakes,
Rivers, and Canals, the teacher should remember that children
at first note only the presence of water. Then they note the
14 Longmans Object Lessons
differences between the three bodies — the water of a river
moves, while that of a canal and of a lake is (practically) at
rest ; a lake is broad in proportion to its length, while a river
and a canal are long in proportion to their breadth ; a river
winds, while a canal is almost straight ; a lake and a river are
natural, while a canal is artificial. Finally, they learn, by wider
observation, or the information of their seniors, that the lake,
river, and canal familiar to them are typical, and they are
then ready for classifications and definitions. To begin, there-
fore, with classifications and definitions, as young teachers,
copying the method adopted in text-books (perhaps for con-
venience of reference) often begin, is to reverse the order of
nature.
2. That part of the subject which most readily connects
itself with the previous knowledge of the children should be
^ placed first. New ideas, when not arising from the
knowledge presentation of new objects, must be formed by the
should be
joined to modification of ideas already possessed. The idea,
for example, which a child who has not seen a lake
forms of it is a modification of his idea of a pond. If a new
topic introduced is not brought into relation with what has
gone before it must fall for want of support. Furthermore,
association is the most valuable principle in mnemonics, and
the connecting of the new idea with the old is a great help to
the remembering of both.
3. A mental survey of all the information to be conveyed
will sometimes show that if certain facts were presented first all
3. Elicit- 'he rest would follow naturally in a train of inductive
'"S- reasoning. If a lesson on the Swallow, for instance,
began with the food, the teacher could make the children infer
that the bird can be with us in summer only, that it must live
chiefly on the wing, and that its structure must, therefore, be
what it is.
Matter of Lessons 1 5
4. Whatever may be the starting-point, the lesson should
progress from it without break or turning. If a teacher, for
4. Direct- example, giving a lesson on the Chemistry of a
"'=^'*- Candle began with the products of combustion, he
would have to go back in order to show whence they are
derived.
5. There should be no attempt at a uniform arrangement
of the matter. Young teachers have a tendency to stereotype.
Arranc'e "'" ^^^^ ^^^" ^ score of lessons on the same subject
ment arranged exactly alike. They all began with an
should not , ^ , . , , , , „
be stereo- Introduction, proceeded to ' Properties,' and (after
'^P'^ ■ intervening heads) ended with ' Uses.' A formal
introduction is sometimes useful and sometimes necessary. It
is useful when the teacher is skilful enough by means of it to
awaken interest in what is coming. It is necessary when a
reference to preceding lessons forms the basis of the teaching
about to be given. In all other cases it may be omitted with
advantage. ' Properties,' too, may be omitted when they are
obvious, when the children are familiar with them already, or
when they have no bearing on what is to follow. The same
remarks apply to ' Uses,' and, as a general rule, it is bad to
separate ' Properties ' and ' Uses,' for the second depend upon
the first.
NOTES OF LESSONS
In school work, as in all other work, forethought and labour
are the price of success, and a teacher who tries to give a
The need lesson without adequate preparation courts failure,
for notes, jj jg ^^^ enough for him to have a general or even a
minute knowledge of his subject. He must consider what are
the facts to which he will draw attention, which of these he
must tell and which he can elicit, what is the best order for
l6* Longmans' Object Lessons
presenting them, what illustrations will throw most light upon
them, and what exercises will most deeply impress them upon
the minds of his pupils ; and experience has shown the advan-
tage of noting down these points.
The fulness of a teacher's notes of a lesson will depend
largely upon whether they are meant for his own use alone or
Full or for the inspection of another. If for his own use
brief notes, alone, they will, so long as he is dealing with a
familiar subject, give only the heads of the matter, and brief
hints of the methods and illustrations. When the subject is
unfamiliar the matter will be given much more fully.
Pupil teachers in elementary schools, students in training
colleges, and all who submit to the examinations of the English
Education Department, have very often to write notes.
Full notes. .
not for their own use, but to show a master, inspector,
or other critic how they would give a set lesson. In these
cases the notes must be self-explanatory, and indicate clearly
both what would be taught and how it is proposed to teach it.
Granting that the execution of the lesson is equal to its con-
ception, these full notes would give a reader almost as good an
opportunity as a hearer would have had of estimating the skill
of the teacher, but this implies that they should, in addition to
presenting a clear outline of the matter, show the method with
considerable fulness. Such meagre directions as ' Elicit,'
' Deduce,' 'Draw from children,' 'Get this from class by ques-
tioning,' are useless, because exactly how the teacher is going
to elicit, deduce, draw from the children, or get from the class
by questioning is just what one wants to know. A minute
description of the process might be tedious, but an outhne of it
should be given sufficiently full to convey clear notions to any-
one who has the technical knowledge necessary to the under-
standing of it.
Notes intended for inspection by others than the writer are
Notes of Lessons if
in England generally set forth in one or two forms. Either the
hints on method are intermingled with the matter, as in
Form of t^e lessons given in this book, or the matter and
the notes, niethod are kept distinct, as in the lesson on the Cat
given in the Appendix (p. 276). Each form has some advantages
to recommend it, though it matters little which is adopted.
However carefully notes may be prepared, they are not
necessarily to be followed rigidly in the giving of the lesson.
Deviations Notes are made for the teacher, not the teacher for
from notes, jj^g i^iotcs, and if, in front of his class, he discovers
that the children have a greater or a smaller knowledge of the
subject than he gave them credit for, or that he has misjudged
the difficulty of teaching any part, he should, as the lesson pro-
ceeds, adapt himself to the une.xpected conditions. To do
otherwise would be to pay tithe of mint and anise and cummin,
but to neglect the weightier matters of the law.
ILLUSTRATIONS
A teacher's character maj', to a great extent, be inferred
from the way in which he illustrates his lessons. If he lacks
liiustra- industry, he will either not illustrate them at all, or
index To ^^ ^^'^^' illustrate them with whatever chances to be
character, available at the moment. If he lacks foresight, he
will fail to provide some illustration that is absolutely necessary,
or the illustrations that he provides will prove ineffective
because some essential detail has been overlooked. If he
lacks originaUty and ingenuity, his illustrations will be far-
fetched, or they will be spiritless copies of something that he has
seen or heard of. On the other hand, the teacher who is dih-
gent, prescient, and ingenious foresees and provides all the
c
l8 Longmans' Object Lessons
illustrations needful, adapts to his needs whatever may be
within reach, and ensures success by a careful attention to
details.
It is hardly possible to lay too much stress on the import-
ance of fully illustrating Object Lessons ; for an Object Lesson
Import- that is not fully illustrated is a contradiction in
mustra- terms and a foredoomed failure. The primary
tions. purpose of an Object Lesson is the cultivation of
the perceptive powers, and this purpose is entirely defeated
if the teacher does not offer materials for the exercise of the
children's senses. An Object Lesson without illustrations is
like a swimming lesson without water or a singing lesson with-
out sound. The illustrations are not an ornamental fringe ;
they are the ver)- warp and woof Their function is not, like
the pictures in our novels, to add to the interest and clearness
of the story ; rather, like the pictures of the ancient Mexicans,
they are the story itself
Where available, the best possible illustrations for an Object
Lesson are actual objects. Pictures are worth having when
Kinds of nothing belter can be had, but the illustrative value
illustra- Qf {]-,g ygj-y jjgjt- pictures is small compared with that
I. Actual of the things themselves. This is especially so in
objects. those very cases in which inexperienced teachers
most frequently use pictures — that is, when the lessons are
about animals. A picture of a cat, for instance, will not show
the roughness of the tongue or its spoon-like action when
lapping ; it will not show the pads beneath the feet, or the
projection and retraction of the claws ; it will not show the
sheaths that protect the claws, the arrangement of the fur, or
the effect of light upon the pupils ; all of which can be abun-
dantly and easily demonstrated from a living specimen. Simi-
larly, a picture of a fish would show the shape and position of
gills and fins ; but a gold-fish in a bowl, or even a sticklebat in
Illustrations 1 9
a jam-bottle, would show these even better, and would, in
addition, show gills and fins at work.
In order to illustrate lessons on animals in the way sug-
gested, there is no need for the teacher to turn his school or
his home into a menagerie. Many children keep
pets, and would be pleased if the teacher were to
borrow them for the purposes of a lesson. I have seen lessons
on the Dog, the Cat, the Hen, the Rabbit, the Pigeon, and the
Lizard illustrated with animals thus borrowed, and the most
delighted member of a delighted class was the proud owner,
who was allowed to stand in front and look after his own pet.
Many animals not usually kept as pets may also be obtained
with a little forethought. I have seen lessons on Rats and
Mice, Snails and Slugs, the Frog, the Swallow, the Sparrow,
and the Bat illustrated with living specimens caught by the
teacher or his friends. And animals that may be difficult to
obtain alive may often be easy to obtain dead. I have seen
dead Herrings, Mackerel, Crabs, Lobsters, and Oysters used
with admirable effect ; indeed, they were in some respects more
useful dead than alive, for, as they were dead, the teacher was
able to dissect them, and thus show their internal as well as
their external structure. I have also seen lessons on animals
illustrated with specimens stuffed or otherwise preserved. I
remember, in particular, a most interesting lesson on the Croco-
dile illustrated with a small stuffed specimen which the teacher
had borrowed from a friend who had brought it home from
Egypt. I also remember effective lessons on Butterflies,
Beetles, Humming-birds, and Serpents illustrated with pre-
served specimens.
It is obvious that there are many natural history lessons
which cannot be illustrated with living or dead specimens.
Some animals are too big, some are dangerous or
Parts of o ^
animals. disagreeable to handle, and many are impossible to
c 2
20 Longmans' Object Lessons
procure ; and in these cases the teacher is compelled to fall
back upon the best available substitutes. Where a whole
animal cannot be used or cannot be procured, parts are useful,
and with a little luck and some thought the school museum
may be well stocked with these. The teacher's own dinners
will furnish the shoulder-blade of a sheep, the head and limbs
of a rabbit or hare, the heads, feet, and typical feathers of hens,
ducks, geese, and turkeys, while, if he keeps his eyes open and
has ordinary good fortune, he can pick up or procure the skulls
or parts of the skulls of many common animals, and the heads
of many common birds. Aided by these specimens, the teacher
can give many valuable lessons on structure. Thus he can
give lessons on bones, teeth, and feet generally ; he can show
the relation between the teeth and food of various mammals ;
and he can connect the beaks and feet of birds with their food
and habits.
Lessons on indigenous plants, too, should be illustrated
with the actual things, and here, happily, there is no difficulty
about obtaining specimens, as the build of roots.
Plants. 1 , ri , , ,- ■
stems, bark, fibre, leaves, wood, seeds, and fruit can
be abundantly demonstrated from material growing in profusion
everywhere. Even in the case of foreign plants, the teacher is
not entirely dependent upon pictures. Tea-leaves, for example,
can be taken from the pot and pasted on white card ; tobacco-
leaves, cocoa and coffee berries, maize heads, cork bark, and
many other vegetable substances can be obtained at the
shops.
Lessons on manufactures may often be illustrated with
actual things. If the teacher himself lives, or if he has a friend
Manufac- ^^^''^S' "'' '^^ district where any manufacture is carried
tures. on, he will be able to get specimens showing every
stage from the raw material up to the manufactured article. If
the school museum does not show the processes through which
Ilhtsirations 2 1
wool, cotton, flax, iron, pens, pins, cork, and sundry other
products pass, the teacher must be wanting in energy or luck.
It greatly adds to the value of a lesson on a manufacture
for the teacher to be able to imitate, no matter how roughly,
the actions that he is describing. His descriptions
Processes. .,, . , ■ • , • , , ■,,
will gam much in interest and in clearness, and will
be far better remembered than if he trusted to words alone. I
have seen the making of soap, paper, bricks, and pottery illus-
trated in this way. I have seen a hat pulled to pieces and
re-made ; a lock, a knife, and a clock put together, and a book
bound in the presence of a class.
AVhatever may be the subject of the lesson, and whatever
may be the specimens used to illustrate it, the children must
see them, and, where the nature of the specimens
tions must permits, handle them also. An object held before
the class appeals to only one sense, and, if small,
appeals imperfectly to that. Even a crown-piece is not of
much use to illustrate a lesson on coins ; but if a penny were
given out to every child the various stages in the minting would
become quite clear. Lessons on leaves, flowers, the parts of
a flower, seeds, and many other subjects should be similarly
illustrated by letting every child have specimens — indeed,
could not be properly illustrated in any other way.
In speaking of illustrating by objects, I have assumed that
the school has a museum. This need cost very Httle, because
^ , , when a good dust-tight case with a glass front has
School ° ° • °
museum. been provided, the expense is practically over. Many
useful things the teacher can furnish from his home stores ;
many animal and vegetable products can be obtained for the
trouble of picking up or asking for ; children and friends will
become large contributors when once they are made to under-
stand that illustrative objects and not curiosities are wanted ;
and most of the leading manufacturers, with a courtesy which
22 Longmans' Object Lessons
cannot be too gratefully acknowledged, are ready to furnish
samples of their wares in every stage of production. In ar-
ranging his series of lessons the teacher will have the museum
in mind, and now and then set a subject, not because it is
essential that it should have a place in the series so much as
because he has at hand abundant means of illustration.
The most effective illustration of a lesson is the actual thing
spoken of ; the least effective is a picture of it. Between the
two come models, which, being only imitations, are
2. Models. ...
not so effective as real objects ; but which, being
capable of examination from all sides, are more effective than
pictures. In every good Kindergarten and infant school toys
and other models are much used, but they are rarely seen in
the senior departments. This is a pity, because even a rough
model will add wonderfully to the clearness and interest of a
lesson. A lesson on the Mountains and Rivers of a country,
for instance, almost gives itself when the contours are shown
in clay or plaster. No picture and no description can make
the children understand the working of the common pump
half so well or half so quickly as a model which can be con-
structed in half an hour out of glass tubing, and I have seen
the working and internal structure of a steam-engine illustrated
with a sectional model in cardboard, which did not take many
minutes to prepare. In the best Continental schools lessons
in natural history are always illustrated with life-like models,
though I have never seen any used in England.
Though pictures are the least effective illustrations, they
are by no means to be despised, and, where nothing better
can be had, they are indispensable. The pictures
3. Pictures . , ,
in the market are often excellently adapted for their
purpose, but the supply is not yet adequate.
The characteristics of a good picture are three : —
I. It should be large enough to be seen by a whole class at
Illustrations 23
once. If a small picture is placed in front, only a few of
Should be ''^^ children can see it properly, and if it is carried
large ; through the class little good is done, because a clear
conception cannot be formed from a brief glance.
2. A picture should be artistic, though artistic excellence
should not be its chief or only recommendation. Its primary
Should be purpose is to illustrate lessons, and if it is not suitable
artistic ; Jq^ jj^jg^ artistic merit will be an insufficient com-
pensation. Some publishers, overlooking this elementary fact,
have issued beautiful pictures which are poor illustrations.
There is, for example, a series of heads of animals admirably
drawn and printed, and well adapted for copies, but almost
useless as illustrations ; for how can a teacher give a com-
plete lesson on an animal when all that he can show is a
representation of its head ?
3. Pictures of native subjects should be of native origin.
It matters little to the English teacher, as teacher, whether his
Sh Id b picture of a Uon was produced in London, Paris,
of native Berlin, or Vienna, but it matters very much where
origin,
his picture of a cow is produced. He cannot and
does not want to show every kind of cow ; his purpose is best
served by showing a typical English cow, but if he has a
foreign picture he will be able to show only a typical French
or German cow. The same remark appUes to all domestic
animals and to all familiar scenes, and yet one often sees,
especially in infant schools, pictures of horses, cows, sheep,
and dogs which are not exactly like anything that has ever
come under the observation of the children — farmers with caps
and curved pipes, carpenters with blouses and wooden shoes,
and washerwomen with battoirs. The pictures, as pictures,
may be excellent (though in many cases they are very much
the reverse) ; but let their artistic merit be what it will, they
are not of much use out of the countries in which they were
24 Longmans' Object Lessons
produced, because elsewhere they offer few points of contact
with the daily life of the children.
g, , A drawing on the blackboard may often be used
board instead of or with printed pictures. Such a drawing
drawings.
has several advantages.
1. It awakens interest by being produced before the class.
2. It assists the attention and the memory by presenting
only those details that the teacher wishes to emphasise.
3. It is always available.
4. It can be more easily copied by the children than an
elaborate printed picture, and the act of copying will help to fix
the lesson in the mind.
The blackboard drawing can be made to supplement the
printed picture —
1. By showing the inside and the ' other side.'
2. By showing on a large scale parts of the picture too small
to be seen by the whole class.
3. By showing successive stages in the growth or develop-
ment of the object portrayed.
The use of coloured crayons will make blackboard pictures
much more effective and much more interesting.
Every lesson that deals with even the elements of physical
science should be amply illustrated with experiments. Children
5. Experi- niust receive scientific facts, not on the authority of
ments jj^gj^ teacher, but on the authority of their own
senses, and if a direct appeal is not made to the senses, the
lesson had better not be given. As has already been said, the
object of science teaching is to foster the habit of observation
and to store the mind with useful knowledge ; and how can
observation be fostered when there is nothing but a teacher and
a blackboard for it to be exercised on, and how can the mind
be stored with useful knowledge when words are made to take
> Illustrations 25
the place of things ? I have seen a lesson on the Composition
of Air given without a single experiment ; for any real good it
did it might as well have been given in Greek. If the teacher
had prepared jars of oxygen, nitrogen, and carbonic acid he
could have made the children see the properties of each gas ;
he could have demonstrated that substances burn very rapidly
in oxygen, and will not burn at all in nitrogen ; he could have
elicited the necessity for ' diluting ' oxygen with nitrogen ; he
could have shown the proportion of the two gases in the air, and
made clear that carbonic acid is a product of combustion (and
of respiration).
All experiments should be carefully prepared, and delicate
or difficult experiments rehearsed. Failure is often due to the
Should be neglect of some apparently trivial detail. I have seen
prepared ^ lesson on Oxygen entirely miss its mark because
the teacher had forgotten to provide matches to light the sub-
stances that he had intended to burn in the gas. Similarly, I
have seen a teacher who had to give a lesson on Magnets spend
five minutes making in the presence of the class preparations
which he should have made beforehand, and, after all, break
down because he had no magnet. Teachers should consider
that the failure of an experiment is a serious matter, because it
may mean the failure of the lesson, and it must mean waste of
time and loss of esteem.
To prepare and to perform experiments is not all. I have
known teachers prepare experiments carefully and perform
And ex- them skilfully and yet do little good with them, for
plained. ^^^ experiment is not necessarily an illustration.
Every experiment exemplifies some principle, but it does not
illustrate the lesson unless the teacher makes perfectly clear
what the principle is, and hozti the experiment exemplifies it. It -
is not enough, for instance, if a teacher wants to show the
relative proportions of oxygen and nitrogen in the air, for him
26 Longmans' Object Lessons
to say, ' A fifth of the atmosphere is oxygen and the re-
mainder chiefly nitrogen,' and then perform the usual experi-
ment of burning phosphorus under a bell-jar placed in water.
He should, first of all, make clear, by a series of questions, that
the jar, at the beginning, contains only air — that is, contains
only oxygen and nitrogen. Then he should similarly make
clear that the burning of the phosphorus exhausts the oxygen ;
that the phosphorus goes out before the whole of it is consumed
because there is no more oxygen ; that the water rises to take
the place of the gas used up, and that therefore the height of
the water is the measure of the oxygen and the space above is
filled with nitrogen. So treated, the experiment would be an
illustration as well as an experiment.
Young teachers sometimes seem to think that experiments
are introduced merely to interest and amuse. I saw one
„ teacher who had to give a lesson on the Pressure of
Experi-
merits are the Air lecture for half an hour, and then spend ten
not for . . . , ,
amuse- mmutes over a few poor expenments ; and another,
'"'^"'' who had to give a lesson on Fusible Substances,
perform all his experiments together at the end — apparently
as an after-thought. Experiments do interest and amuse, and
if they did nothing else they would be worth having ; but,
properly used, they do far more. They do even more than
make the children understand — they make them discover.
They should, therefore, be the foundation of the teaching, not
an ornamental addition. The same remark applies to other
illustrations.
27
LANGUAGE
In treating of the selection of matter, I referred to the abuse
of technical terms. Inexperienced teachers seem to think that
Technical ^vords of learned length and thundering sound are a
terms. necessary part of every Object Lesson. They intro-
duce such words freely, strive hard to explain them, and de-
lude themselves into a belief that they are teaching science
when they are not even teaching the terminology of science,
for the only way in which we can make children really under-
stand words is to make them familiar with the things to which
the words apply. I do not say that technical terms should
never be employed, but I do say that they should be employed
sparingly in Object Lessons. The proper time for them is
when the definite study of science is undertaken ; before that
they should be employed only when their use obviates long
circumlocutions, or when there are no short and simple names
for the things denoted. To speak, as I heard a teacher speak
in a lesson to young children on the Spider, of palpi and a
cephalo-thorax is worse than useless — it is giving a stone for
bread.
A teacher's language may be entirely free from technical
terms, and yet be almost unintelligible from its ' bookishness.'
■ Bookish- Only a long experience of children enables one to
ness.' realise how narrow are the limits of their vocabulary.
The hmits vary, of course, with the character of the homes; but,
even when the parents are educated, young children have not a
large stock of words, whereas when the parents are uneducated
the stock is very small indeed, and simplicity becomes doubly
a duty. It has been stated that an illiterate hind can express
the whole of what are called his ideas with 400 words. This
28 Longmans' Object Lessons
number is probably under-estimated,' but there can be no
doubt that uneducated people know the meanings of com-
paratively few words, and that their children know the meanings
of still fewer. A teacher is, therefore, not likely to be under-
stood when he speaks to such children of ' subjecting butter to
the influence of heat,' of ' bringing a flame to bear on a fusible
metal,' or of a reptile's tongue having 'an adhesive substance
at its extremity,' and it should never be forgotten that if our
pupils have to think about our words they cannot be thinking
about our thoughts. A teacher's language should be trans-
parent — not like a stained-glass window, which may in itself be
worth study, but which obscures or e.xcludes the surrounding
world.
A teacher should aim at speaking so as to be understood by
all his pupils — if he does not want to be understood, why
should he speak ? — but to make his meaning clear
he should never resort to mean colloquialisms, to
slang, or to provincialisms. His language should be a model
of purity as well as of simplicity, though it would be pedantry
to set up as high a standard of style for speaking as for
writing.
1 An American writer, after a careful inquiry into the number of words
used by various classes, comes to the following conclusions : —
' Every well-read man of fair ability will be able to define or understand
20,000 or 25,000 primitives and principal derivative words.
' The same man, in his conversation and writing, will use not less than
6,000 or 7,000 words. If he be a hterary man he will command 2,000 or 3,000
more,
' Common people use from 2,000 to 4,000 words, according to their general
intelligence and conversational power.
'An " illiterate man " (one who cannot read) will use from 1,500 to 2,500
words.
'A person who has not at command at least 1,000 words is an ignorannis,
and will find difficulty in expressing his thoughts, if, indeed, he have any to
express,'
QUESTIONS
A lecture differs from a lesson. Both the lecturer and the
teacher strive to secure attention by the presentation of inte-
resting facts or the interesting presentation of facts ;
Lecturing '
and teach- but the lecturer looks upon his audience as a whole,
°' while the teacher looks upon his as units. The
lecturer does not hold himself responsible for all his hearers
understanding or for any of them remembering what he says,
but the teacher considers it his duty to make each hearer
understand and remember. The lecturer makes statements,
while the teacher mixes questions with statements ; and what is
meant for a lesson often is only a lecture, because few questions
are asked.
Purposes of ^ '^^^her asks questions-
question- I. To find out what the children know, so that he
ing : —
1. To may avoid waste of time in trying to teach what has
vious '^ been already learned, and may ascertain what is the
knowledge, foundation on which he can build.
2. To convince children of their ignorance, and thus awaken
in them a desire for knowledge. In nearly every class there
are a few children who have too high an opinion of
2. To con-
vince of their own attainments, and who, believing that the
g orancc. ^^^^^Yi^^ [^^^3 nothing new to tell them, are little
disposed to listen. A few searching questions will, without
destroying necessary self-respect, and self-confidence, show
these that they have yet much to learn.
3. A teacher sometimes asks questions to secure attention.
When children allow their minds to wander, nothing
3. To
secure at- SO promptly and thoroughly recalls them to the
business in hand as a well-aimed question.
30 Longmans' Object Lessons
4. A teacher also asks questions to direct and encourage
thought. It is important that children should be made to
remember, still more important that they should be
4. To
direct made to understand, and most important of all that
°"^ ■ they should be made to think. The second includes
the first, because the better we understand a thing the easier
we shall remember it ; and the third includes the first and
second, because if, with or without guidance, we think a thing
out for ourselves, we shall both understand and remember it.
It may be useful to remember such simple formulae as s =z\ft'^
or sin.^A + cos.^A= I ; we are the more likely to remember
them the better we understand what they mean and how they
are applied ; we are certain to remember and understand them
if we can go through the processes by which they are arrived
at. The opportunities which different subjects of study afford
for the cultivation of the thinking powers vary greatly ; the
degree to which different teachers avail themselves of those
opportunities also vary greatly ; and it may be safely asserted
that that subject possesses the highest educative value which
affords most opportunities for quickening thought, and that
that teacher is the best educator who most fully avails himself
of the opportunities afforded.
'Whatever may be the purpose for which questions are asked,
certain general rules apply to them.
I. They should be clearly and concisely worded. Before
beginning to speak, the teacher should form a perfectly definite
^ , , idea of what he wants to ask, and then ask it in such
Rules for
i questions : a way that the pupils shall also form perfectly definite
be clearly ideas. How could children be expected to follow
^°' "^ ■ the following question with which I heard a teacher
introduce a lesson on Frogs : ' If any of you boys were to go
into the country in the spring-time in the commencement of
the year, and you go near a stream in the country, in some
Qicestions 3 1
parts you will almost be sure to see a lot of them (little things)
jumping about and in the grass. What would they be ? ' What
has been said generally about the language of lessons of course
applies to the language of questions. 'What does a plant
derive its life from ? ' is a concise question, perfectly clear — to
those who understand it — but asked, as it was, to children of
eight, it was unintelligible.
2. Questions should be definite enough to call forth the
answer desired. ' AVhy is this lamp burning ? ' ' What do we
2. Should always find in the school-room in the day-time ? '
be definite, i 'What are we always doing ? ' are types of questions
likely to lead to much waste of time, because the teacher may
get twenty correct answers before he gets that which he
wants.
3. It follows that questions should admit of only one correct
answer. Such a question as ' What do you notice about this ? '
3. Should (some object presented to the class) may appear
onw'one justifiable, nay commendable, because it requires an
answer. exercise of the children's own powers of observation,
but there is a danger of its bringing answers which are irrele-
vant, or which cannot be used at that stage of the lesson.
' VVhat do you notice about its weight, shape, colour, head,
eyes, teeth, fur, &c. ? ' would have all the merits of the vaguer
question and be free from its defect.
4. Questions which admit of only two correct answers
should not be asked. If I ask, ' Is this metal hard or soft ? '
4. Should ' Uid Richard follow the advice of his father ? ' one
not admit |- jj^ ^ possible answers is, as a matter of chances,
of only two " r > i
answers. ^g likely to be Correct as the other, and there is little
incentive for children to think when the probability is so small
of their being wrong if they do not think. Besides, when the
wrong answer has been rejected, the right one can be given
without any thought whatever.
32 Longmans^ Object Lessons
5. It follows that no question which would encourage guess-
ing should be asked. Guessing is encouraged directly by such
5. Should questions as, ' What do you suppose the size of a
co'irag'e cotton plant is ? ' ' Who thinks that it is six feet
guessing, high ? ' ' Hands up boys who think cork will burn ? '
and it is encouraged indirectly by asking questions which the
children cannot reasonably be expected to answer, such as,
' What is put on the land to make it rich again after the
tobacco crop ? '
6. A question should not, as a rule, be asked on the
substance of a statement immediately after the statement has
6. Should been made. If children are told, ' Bricks are made
asked'^im- '^^ clay,' and at once asked, ' What are bricks made
mediately ^fpi j^gy q^^ gjyg {^g right reply without thought,
ment. A question immediately after a statement may be
necessary when a child has to be convicted of inattention, or
when the subject is so very difficult that the teacher must make
sure at every step that the children are following him.
7. Questions should be well distributed. Some teachers
confine their questions to the children immediately
7. Should ^ ^
be well dis- in front of them, some to the bright, and some to
ti'ibuted. . J ,,
the dull.
8. Questions should not be repeated, as repeti-
not be tion on the part of the teacher invites inattention on
epca c . ^^ p^^^ ^^ ^^ scholar.
A statement ending with an ellipsis to be filled up is a form
of question requiring the least possible exertion from the pupils,
and is, therefore, a form which should be employed
Ellipses.
only when there are sufficient reasons for making the
work specially easy. The ellipsis, moreover, requires careful
treatment. There ought to be but one way of filling up the
blank correctly, and to find that way ought to require thought.
'Wheat grows in . . . ,' 'The motion of the earth on its axis
Questions 33
causes day and . . . ,' and ' The molecules are kept together
by the force of co- . . . ,' are all examples of bad ellipsis ; the
first because the most thoughtful pupil might feel some doubt
about the word desired, the second and third because the most
thoughtless could feel no doubt whatever.
Some attention should be paid to the wording of the
answers as well as of the questions. Answers that are too brief
Wordincof should HCver be accepted, even though correct in all
answers. ]^^^ form. In the best Continental schools complete
sentences are required in replies. This is a most valuable
preparation for written composition, and though it may be
pedantic to insist upon complete sentences always, there is no
pedantry in objecting to such highly elliptical answers as the
following : ' What happened to the wax when I held it above
the flame ? ' [Liquid.] ' What is the meaning of evergreen ? '
[Always.]
An ungramniatical answer should never be accepted. Cor-
rectness of speech is much more a matter of habit than of
rules. The children of educated parents speak cor-
Ungram-
maticai rectly before ever hearmg of grammar, whereas it
answers. .^ ^^^ ^^^^ ^^ j^^^^ children who have been taught
to parse and analyse very well speaking incorrectly. Every
opportunity for assisting the formation of a good habit should
therefore be seized, and an ungrammatical answer is perhaps
the opportunity which occurs oftenest. Suppose such an answer
as ' They was too old ' to be correct in substance. The teacher
should explain that it was right in fact, but wrong in form.
The child who gave it might then detect the error ; if not, the
teacher might proceed, ' You said, " They was too old ; " what
ought you to have said ? ' There would have been no men-
tion of grammar, and yet a valuable little lesson in grammar
would have been given, for 'a child shall take more profit
of two faults gently warned of than of four things rightly
34 Longmans' Object Lessons
hit." The elder pupils could be made to see why the
wording of an answer is wrong, but the teacher should not
be tempted into digressions. He might make a note of the
error, and use it as a text for the next grammar or composition
lesson.
TELLING AND ELICITING
Jacotot, who maintained that a teacher should tell his
pupils nothing, would be surprised and disappointed could he
see how many teachers of the present day act as if it
Jacotot.
were their duty to tell their pupils everything. I he
precept of Jacotot was not altogether reasonable, and the prac-
tice of the teachers to whom I have referred is not altogether
unreasonable. He forgot that we have to inform as well as
educate ; they forget that we have to educate as well as inform.
If children acquire only such knowledge as they can discover,
or be made to discover, for themselves, they must remain
ignorant of very many things that it is necessary and useful for
them to know ; and they cannot enter into possession of the
rich heritage of wisdom and experience bequeathed to them by
the past, because if it is wrong for them to learn from a teacher
it must also be wrong for them to learn from books. On the
other hand, telling children too much allows their faculties to
lie fallow, and their capability and god-like reason to fust in
them unused.
Jacotot's precept must be modified before it can command
universal acceptance : A teacher should tell his pupils nothing
Too much that he can make them find out for themselves in
telling. school without waste of time. Many things— all
historical and most geographical facts, for instance — they
must learn from books, which is only another form of telling ;
- ' Roger .'Ischam.
Telling and Eliciting 35
still there can be no doubt that children arc told much that
they ought not to be. Their memories are stored, instead of
their faculties being developed. They are exhorted to open
their mouths and shut their eyes and see what good things the
gods will send them, instead of being made to earn the good
things by their own exertions.
The innumerable illustrations that might be given of need-
less telling divide themselves into two classes. Teachers tell
liiustra- ^^h^' children could find out by the exercise either
tions. q£ their own senses or of their own reasoning powers.
A teacher giving a lesson on Tobacco will tell his pupils that
snuff is a fine brown powder, when, actually having some snuff,
he could make them describe its qualities, presuming that they
are worth dwelling upon ; or, giving a lesson on a Coin, he will
first tell them that it is composed of certain metals, and then
tell that these metals are melted and mixed, when he could
have made them infer the second fact from the first.
In dealing with the arrangement of the matter of a lesson, I
spoke of the possibility of starting with one fact and then
making children infer other facts from it. When, for
Eliciting. .
example, a teacher has shown the situation of the
British Isles he can elicit why the west coasts are indented ;
why the east wind is dry and cold and the south-west wind wet
and warm ; why more rain falls in Ireland than in England,
and in Westmoreland than in Norfolk ; why Liverpool is the
port for the American trade and Lancashire the seat of the
cotton manufacture ; and why we are a nation of shopkeepers.
In lessons on animals, again, the same process can be carried
on to a great extent. The food of cats and horses can be
deduced from their teeth ; the digestive organs of a hen from
its want of teeth ; the teeth of a mouse from the fact that it can
gnaw through boards ; the speed of a greyhound from the
animal's broad chest and long sinewy limbs ; the aquatic habits
D 2
36 Longmans' Object Lessons
of a duck from its webbed feet, and the short legs of a swallow
from its long wings ; and no injustice would be done to a
teacher if his skill and the educative value of his lessons were
measured by his success in making children reason out conclu-
sions from observed or stated facts.
One sometimes hears a kind of counterfeit eliciting, wherein
the questions are directed, not to making children think, but
Counterfeit '0 making them give a certain word. An infant-
eiicitmg. school teacher points to a letter and asks what it is.
There being no answer she proceeds, ' What makes honey ? '
The child replies, 'A bee.' 'Yes,' says the teacher, 'and this
letter is B.' Another teacher shows some tallow and asks
what it is. The children reply, 'Fat, lard, dripping.' Instead
of making them smell it he says, 'What are candles made of?'
and thus gets the word desired without any exercise of the
children's senses or intelligence.
EMPHASLS
The process of crystallisation is full of suggestion to the
teacher. A saturated solution of the substance to be crystal-
Crystallisa- I'sed is made and allowed to evaporate ; threads are
"'^"- suspended in it, and around them the crystals form.
In every lesson there should be threads. In a lesson on
Winds, for instance, unless the children can be made fully to
realise the fact that heated air rises they will gain nothing.
When the teacher has, by illustration, explanation, and recapitu-
lation, made the fact clear in all its bearings, till it has become
a part of the children's working knowledge, he can proceed to
show the application of it in the production of wind. Then,
whatever may be forgotten, the leading principle will be remem-
bered, and the children will be able to group the rest of the
Emphasis • 37
lesson around it. The principle will be the thread on which
the information crystallises.
One often finds in the lessons of inexperienced teachers an
entire absence of threads. The fundamental facts are not
i,;o emphasised, essentials and accidents are treated
emphabib. jdii^e^ with the result that children form no idea of
the lesson as a whole, and perhaps remember an illustration
but forget what principle it was intended to make clearer.
AVhere emphasis is not entirely absent one sometimes finds
it in the wrong place. The most important parts of the lesson
Wroiw '^'^£ allowed to take care of themselves, while great
emphasis, gfj-ess is laid on something incidental. In a lesson
on Coins, for example, the teacher was silent on the necessity
of alloying gold and silver, but he gave the exact proportions
of the metals in each kind of coin, wrote the numbers on the
board, and had them repeated till the figures were learned by
heart. He thus caused a great deal of time to be spent in
l^ibour which profited not, and the only comfort was that the
children would soon forget what he had been at such pains to
teach.
SUMMARY
A good blackboard summary of the lesson is a great aid to
proper emphasis, because it calls attention to the leading, and
^j(j (Q only to the leading facts, which are otherwise likely
emphasis, jq ]-|g jogf gjgj^j- gf behind a mass of details. A good
summary is also a great aid to the memory, because it appeals
to the eye as well as to the ear, and enables a clear and compre-
hensive view of the whole lesson to be taken in at a glance.
What a A summary
shouTd'be. (i) Should be methodically arranged and plainly
written.
38 Longmans' Object Lessons
(2) Should be written little by little as the lesson proceeds,
and not altogether at the end.
(3) Should, if the children are young, contain no hard
words.
RECAPLTULA TLON
A good summary is a valuable help to recapitulation,
because it shows the parts on which most stress ought to be
placed. Children cannot take in much at once —
y here
must be how much they can take in depends on the nature
of the subject — but, whatever the subject may be,
the teacher must, after proceeding a little way, pause to revise.
Recapitulation
(1) Should come immediately after the enunciation and
explanation of fundamental principles, because it is useless to
go on building before ascertaining that the foundations have
been well and truly laid.
(2) Should come at every natural break in the lesson.
(3) Should at the end of the lesson be twofold, first to
deepen the impressions that have been made, and then (without
the summary) to show whether the lesson has been effectively
learned.
(4) Should be chiefly in the form of questions. To re-tell is
almost useless, because the facts have lost the charm of novelty,
and little mental effort is required merely to listen to them a
second time.
Part II.
FULL TEACHING NOTES
OF
COURSES OF LESSONS
ON
ELEMENTARY SCIENCE
[If the following Lessons are given at the rate of one a week, and
thoroughly revised from time to time, they will provide work for four
years. They are intended for children from seven or eight to ten or
eleven. Hence the book offers to the first four Standards in the Public
Elementary Schools of Great Britain a course of Elementary Science lead-
ing up to the specific study of Mechanics, Physiology, Botany, Chemistry,
and Physics,]
NOTES OF LESSONS
FIRST YEAR
A : Lessons on Common Properties
SOLVE A^TS AND SOLUTIONS
[Two lessons, the division being left to the discretion of the teacher.]
Evaporation. — Pour a little water into a watch-glass or
evaporating-dish, and place over a Bunsen burner or spirit-
lamp. When vapour begins to rise ask, 'What is this?'
Children will answer 'Steam,' and there is
no need at present to bring in the terms
vapour and evaporation. ' JVhat zvas it be-
fore it 'was steam ? ' ' JI'7iat changed it into
steam ? ' Continue the evaporation till the
water has entirely disappeared. Show the
dry dish, and emphasise the fact that the
heat has made the whole of the water pass
away into stearn.
Solution. — Drop a lump of loaf sugar
into a tumbler or test-tube containing clear
° r !(.. I.
water. Let the children watch the sugar
dissolving. ' IF/iat has become of the sugar 1 ' The children
will answer that it is melted. Say that dissolved is the word
commonly used. ' JV/iere is the sugar ? ' ' ILoici do you knoiv
that it is ill the water ? ' Let the water be tasted. Explain
that the sugar has been divided into very little pieces which
are mixed with every part of the water.
Recovery of solution. — ' JLow many things have I put into
this glass V "■ LIow can I separate the sugar from the water?'
42 Longmans' Object Lessons
[Probably no answer.] ' If tlu water were driven away, what
2vould be left in the glass V 'How did we drive away the
water just now ? ' Evaporate some of the solution, and let the
children see and taste the sugar recovered. [To save time,
and to obtain good results, the water should be saturated with
sugar, and only a little of the solution evaporated.]
A saturated solution. — Into a small glass containing cold
water drop finely powdered nitre (saltpetre), a little at a time,
and stir with a glass rod. IVIake the children observe that
the nitre is dissolved. Continue to add nitre till it begins
to fall to the bottom of the glass. Thence bring out the
general fact that water will dissolve only a certain quantity of
a thing.
Hot water Pour some of the saturated solution into a
beaker. Emphasise two facts ; (i) That the water is cold : (2)
That it will dissolve no more. Place the beaker above the
burner or lamp. When the water is hot, add more nitre and
stir. It is dissolved now. Thence bring out the general fact
that hot water will often dissolve more of a thing than cold
water.
Soluble and insoluble substances. — Provide a number of
substances, and let the children discover by experiment which
are soluble and which are insoluble in water. Make two lists
on the blackboard. The soluble substances should include
alum, sugar, and copper sulphate, and the insoluble sealing-
wax, camphor, indiarubber, and fat.
Oil. — Half fill a test-tube with water. Pour some oil on
the water. Shake, and show that the oil will not dissolve. To
increase the difference in appearance between the two fluids,
colour the water with red ink or an anihne dye.
Alcohol. — Sealing-wax was just now shown to be insoluble
in water. The wax will dissolve in alcohol (methylated spirit).
So with camphor. A pretty appearance will be obtained if a
httle water is dropped into the solution of camphor.
Benzine. — Fat (which would not dissolve in water) will
dissolve in benzine. This is the reason why benzine is used
to get grease spots off clothes. Illustrate with a greasy
rag.
Solvents mid Solutio
43
^^.^^
Naphtha. — Indiarubber (which would not dissolve
water) dissolves in naphtha. That is the way in which it
dissolved for mackintoshes and other water-
proof articles.
{Preparation for the next lesson. — In the
saturated solution of copper sulphate (blue
vitriol or bluestone) suspend in the presence
of the class a small object (such as a stone),
and say that you will let the solution stand
till the next lesson. In the saturated solu-
tions of alum, nitre, and sugar suspend
pieces of string. Ask the children to do
the same with a solution of alum, and to
bring for the next lesson the strings with all that will
found clinging to them.]
m
is
Fig.
be
CRYSTALS. SALT-MAKING
Crystals.— Ask how many children made solutions of alum
as requested at the end of the last lesson. Examine the strings
and say that the bright little things clinging
to them are called crystals.
Produce the solutions set aside from the
last lesson, and let the children observe the
crystals.
'In what things sold by the grocer do we
see crystals .? ' [Sugar-candy, ' crystallised '
sugar, and salt.] .Show each.
Salt. — In some parts of the country men find on digging
underground great rocks of salt. Show rock-salt. Also show
some table-salt, and question out the differences between the two.
Explain that the difference in colour is due to ' dirt ' mixed
with the salt.
' Who has seen a spring 1 ' ' Where did the water come from ? '
' Suppose the tvater had touched some rock-salt, what would it do
to the salt .? ' Illustrate by dissolving some rock-salt, and say
that salt springs are found in some parts of the country.
Fig. 3.— Crystals of
alum.
44 Longmans' Object Lessons
'How did we get the sugar out of the ivater last lesson V
' Hoiv can men get tjie salt out of the water from salt spr'mgs 2 '
Prepare a solution of salt. It need not be saturated. Evapo-
rate l>y a gentle heat. If the solution is allowed to boil we shall
have a shapeless mass instead of salt crystals.
To get clean salt out of rock-salt men dissolve the rock-
salt, and then let the water pass off in steam. [The other pro-
cesses can at present be ignored.]
SUSPENSION. POROSITY
Solution and suspension, — Drop a little copper sulphate
(blue vitriol or bluestone) into a beaker containing clear water.
When it has dissolved ask, ' What has become of the bluestone ? '
' Can we see any of it 2 ' ' Why not ? ' ' How can we see that
it is mixed ivith the water ? '
Drop a piece of chalk into another beaker containing clear
water. Make the children see that it is not dissolved. Takeout
the piece of chalk and drop in some powdered chalk. Mix
well. ' IJ'hei-e is the chalk now V ' Is it dissolved 2 '' Let the
water stand, and make the children note that the chalk sinks
to the bottom.
Go through the same process with some other insoluble
powder, as coal, charcoal, flour.
' What became of the copper sulphate 2 ' ' IVhat became of
the chalk 2 ' Bring in the term suspended now.
Pour the solution of copper sulphate into the beaker con-
taining the chalk. ' How many things are there now mixed
with this water 2 ' '■The bluestone is ?' '■And the chalk
is ?'
Filtration. — ' How did we separate the salt from the water
in our last lesson 2 ' We will separate the chalk from the water
in another way.
Inside a funnel (of glass, if possible) place a piece of filter-
paper. Blotting-paper will answer the purpose. Filtering-
paper is sold ready cut in circles. If blotting-paper is used
that must be cut into circles. Fold the paper to form a semi-
S?ispenswu — Porosity
4S
circle. Fold again to form a quadrant, then open out so as
to form a conical cup by taking three thicknesses of the paper
on one side and one thickness on the other. Place in the
funnel. [A little water may be necessary to make the paper
stick to the glass.] Pour
the mi.xture very gently to
avoid breaking the paper.
[It is a good plan to let the
mixture run slowly down a
glass rod, the end of which
nearly touches the paper.]
The chalk remains on the
paper, while clear water runs
through.
Pores. — Elicit that the
water could not have run
through if there had been
no holes in the paper.
These holes are called pores,
and the paper is said to be
porous. Elicit also that the
pores must be very small, or
the grains of chalk would
have passed through.
Produce a number of porous substances, such as sponge,
bread, a piece of cane cut diagonally, lumps of sugar and salt,
charcoal, sandstone, brick, blotting-paper, &c. Let the children
examine them, beginning with the substances that have the
largest pores. Ask the children to separate the substances that
have pores from those that liave none.
Fig. 5.
46 Longmans' Object Lessons
The sugar, salt, charcoal, sandstone, and brick will probably
be placed in the second division. Show that these are porous
also. Let the salt and the sugar stand in a saucer containing
coloured water. In a very short time they will be coloured
also. ' What has coloured these 1 ' ' JVAere did it come from ? '
' Ifow did it pass through the salt and the sugar ? '
Treat charcoal in the same way.
Show that the brick and the sandstone are porous by
dropping water on them.
Show that the blotting-paper is porous by making it absorb
some ink.
FILTERS
The essential property of a filtering medium. — Repeat the
filtering-paper experiment of the previous lesson, and elicit why
the water passed through the paper while the chalk remained
behind.
Take out the filtering-paper and put a piece of sponge (not
too fine) in its place. The liquid passed through discoloured.
' ILoiv did the chalk pass 1 ' ' JV/iy did it pass through the pores
of the sponge and not through the pores of the paper ? ' Mix
sawdust with water, and pour on the sponge. ' JVhy did not the
sawdust pass through V Emphasise the fact that if we want to
filter we must use something which has very small pores.
A flower-pot filter. — iVIake a rough filter by placing a
sponge above the hole of a flower-pot, with alternate layers of
powdered charcoal and sand above that. Show its action by
passing water discoloured with some powder (such as chalk,
flour, or charcoal) through it.
A table-filter. — A table-filter, being of glass, is excellent
for the teacher's purpose. Show its action. ' Where is the dirt
which was in the water at first ? ' Hence elicit that the ■
charcoal (or other filtering medium) must be frequently
cleaned.
Use of filters. — Bring this out by a few questions. Recall
the distinction between dissolved and suspended taught in a
Filters 47
previous lesson. Pass through filtering-paper water with
powdered chalk suspended and copper sulphate dissolved in it.
Emphasise the fact that the filter keeps back only the sus-
pended impurity.
Waterworks. — If there are any waterworks in the neigh-
bourhood of the school, the children will be interested to learn
that the filtering-beds do not differ in principle from the flower-
pot filter made in their presence. The water passes first through
a layer of sand two feet deep, then through four layers of gravel
each six inches deep, the gravel increasing in size downwards.
[This is for purposes of aeration, of which nothing need be said
now.]
SUGAR
[Before the lesson let a solution of sugar stand so that crystals
may be formed.]
Sugar-cane. — Sugar is made from the juice of the sugar-
cane. The ' cane ' is a kind of tall, thick, strong grass, which
grows in very hot countries. Show picture, or draw one on the
blackboard. The cane is full of pith inside. Illustrate pith
by showing a fresh-cut piece of elder-wood. The pith is full
of sweet juice (like the pulp of an orange).
Cutting'. — When the canes are ripe they are cut down close
to the ground, and taken to a mill.
Crushing. — There they are passed between large iron
rollers. Compare to a mangle, or illustrate by two reels.
Boiling. — The juice is run into tanks and boiled. When
mother is cooking she sometimes drops a little salt into the pan
to make the scum rise. Lime is thrown into the boiling juice
for the same purpose. The clear juice is then run off.
Make a solution of sugar. ' How can we get rid of some oj
this water ? ' Illustrate. The clear juice is boiled in the same
way till it becomes thick enough to form crystals on cooling.
Show the sugar crystals prepared, and refer to the former lessons
on Solutions and Crystals.
48
Loiigvians' Object Les.
•sons
Molasses. — The juice (which has now become a thick mix-
ture of sugar and molasses) is packed in casks having holes in
Fig. 6. ~ Cutting sugar-canes.
the bottom of them. ' IVhat ivill run out .? ' The molasses is
used in making rum.
Refining-.— The sugar is then sent to England in order to
be made pure enough for use.
(i) It is first dissolved in warm water, a little lime is added
Suo;ar
49
and the mixture is filtered through thick folds of cloth. Illus-
trate. (Fig. 7.)
(2) The syrup is now clear, but it is still discoloured. To
make it white it is filtered through animal charcoal (that is,
charcoal made by heating bones in
closed iron vessels). Illustrate the
filtering.
(3) The sugar, which will form
crystals, must now be separated
from the syrup, which will not.
Remind children of the experiment
in a previous lesson, when salt
crystals were obtained from a solu-
tion evaporated at a gentle heat.
This is the way in which sugar
crystals are obtained. Illustrate.
(4) The sugar is poured into
moulds, formerly conical, now gene-
rally cubical. Illustrate on black-
board. The uncrystallised syrup is treacle. The )noulds are
placed point down, and the last remains of the molasses (now
treacle) settle at the bottom. The discoloured point of the sugar-
loaf is cut off Ask about sugar-loaves seen in grocers' shops.
^^ — ^~'"^i^
sf-,j
IS
^
PLASTIC SUBSTANCES
Plaster of Paris. — Show dry plaster of Paris. Let the
children handle it. Ask them to make it into a ball, flower-
pot, tea-cup, &c. They cannot. Drop the powder into water,
and knead the mixture into a paste. [Remember that plaster
of Paris dries very cjuickly,] Let children again handle it,
and again ask them to make the same things as before. Using
a tea-cup, saucer, or small flower-pot as a mould, make a
similar article. Turn it out or break the mould. Emphasise
the fact that the plaster can be formed into almost any snape.
The mouldings on the cornices and the ornaments on the
ceilings of rooms are made out of plaster of Paris.
E
so Longmans' Object Lessons
Sand. — By way of contrast moisten sand, and show that it
cannot be moulded.
Clay. — Before the lesson thoroughly dry and powder some
clay, and go through the same processes with the powder as
with the plaster of Paris. Among other things mould two
small bricks, and announce that for the next lesson one of
them will be left to dry, and the other will be dried and burnt.
Ask the children to burn some clay and bring it with them for
the next lesson also.
Putty. — Similarly show that whiting cannot be moulded,
but that mixed with linseed oil it forms putty, which can be
moulded. Elicit, in passing, that putty would be of little use if
it did not dry quickly, and then say that linseed oil is used
because it dries quickly. [The litharge which is boiled with
the linseed oil may be ignored.]
Gutta-percha. — Show that it cannot be moulded when
cold ; but that when plunged into boiling water it becomes
soft, and can then be easily moulded. It is made into bags,
bottles, shoe-soles, waterproof sheeting, &c.
Plastic. — ' The plaster of Paris, clay, putty, and gutta-percha
were all alike in one thing; what was that V Things which
can be moulded are said to be plastic. ' Name other plastic
things.'
PRICKS
Produce the two bricks made last lesson, one of which has
been simply dried, and the other dried and burnt. ' Of what
did ive make these ? ' ' Which is the harder ? ' ' lJ7/y ? ' Show
a real brick. ' Of what is this made ? ' ' ]l7iv is it hard?'
Brick-making.— (i) lUustrate mould by a pencil-box with-
out lid or bottom. Mould on a drawing- or other board.
Show that clay will stick to the wood. ' IV/iat does mother
sprinkle on her paste-board 'I ' ' JFhy ? ' ' How shall we keep
the clay from sticking to the hoard ? ' Sprinkle sand on the
board. ' I/irw shall -we keep the clay from sticking to the mould ? '
Children will probably suggest sprinkling sand. Show that the
sand falls off, and thence ehcit that the mould must be damped
Bricks 5 1
inside. Place mould on board, fill with clay, and smooth off
superfluous clay with a ruler. Lift mould.
(2) Show that the brick if not handled very carefully would
lose its shape. Hence elicit that bricks after being moulded
must be left to harden a little.
(3) ' Who has seen a brick-field V ^ Did you notice bricks
drying V '■ Hoiv were they placed V [In long, low walls with
spaces between the bricks.] Get a child to place books
similarly. ' Why are these spaces left 1 ' ' IPith what was the
top of the wall covered 2' [Straw or boards.] 'IFhy?' If the
children cannot suggest the reason, sprinkle a little water on
the dried brick from last lesson and repeat question.
(4) Burning is the next thing done. ' Where does mother
bake her bread V [In an oven.] Bricks are sometimes baked
in a kind of big oven called a kiln. More often they are
placed in heaps. A layer is spread on the ground. [Illustrate
again with books.] A mixture of small coal, cinders, and
breeze (coke broken into little pieces) is strewn over. Another
layer of bricks a little way apart. 'If'hy?' More fuel, &c.
A fire is lit, and when the fuel is burnt out the bricks are hard.
Ready for use when cool.
Differences between clay and bricks.— (i) Let children
feel that clay is soft and plastic, while the brick is hard.
(2) Pour water on both. It soaks into the brick, but not
into the clay.
■ (3) Hammer both. Clay is tough, and the brick britde.
Go through the same processes with some of the clay which
the children themselves have burnt since the last lesson.
ELASTICITY
Elasticity by stretching. — Have a piece of what is fami-
liarly known as ' elastic ' measured. Stretch it ; allow it to
resume its original length, and have it measured again. ' ]Vhat
is this made of 'I ' [Indiarubber.] Emphasise the fact that the
indiarubber gets back to its first size and shape.
Elasticity by pressure. — Show a hollow indiaruldier ball.
52
Longmans' Object Lessons
Make children note the shape. Measure the circumference
with a tape or piece of string. Squeeze the ball. Make the
children see that the shape and size are altered. Allow the
ball to resume its original size, and have it measured again.
Emphasise as before.
Treat a ball of wool and a piece of sponge similarly.
By way of contrast show that a ball of putty or wet clay can-
not be compressed, and will not resume its original shape.
Make the hollow indiarubber ball rebound from the table.
Ask the children to notice whether there is any change in the
shape of the ball when it strikes the table. They will see that
it is flattened.
' Make a solid indiarubber ball similarly rebound from
the table, and a glass marble, a clay or stone marble, and an
ivory ball rebound off the hearth-
stone, or (better still) off a slab
of stone or marble placed on the
table. The flattening in these
cases will not be seen, but its
effects can be made visible if a
slab covered with some colouring
matter be used. Show that when
the ball is made only to touch
it makes a small mark on the
slab, but when made to rebound
it makes a much larger mark,
which is due to the flattening.
By way of contrast show that
a ball of lead, putty, or wet clay
will not rebound. It is flattened,
and will not resume its shape. Emphasise the fact that in the
other cases the ball gets back to its first shape and size.
Provide a bottle with a cork which will hardly go into the
neck. Make the children see that the cork is too big. Then
force it into the neck. Take it out, and make them see that it
is again too big — it has gone back to its first size.
a
If the children are dull or backward omit this paragraph.
Elasticity 5 3
Elasticity by bending. — Bend a piece of thin steel. Make
children note that it goes back to its first shape. So with steel
springs of various kinds.
Elasticity by twisting. — Get a piece of string with a small
weight at the end. Twist ; then hold by the free end, with the
weight hanging down, and make the children see that the string
goes back to its first shape.
The term. — Show ' elastic,' and ask what it is called. Any-
thing which goes back to its first shape and size after being
stretched, squeezed, bent, or twisted, is said to be elastic.
Degrees of elasticity. — We have seen that some things are
very elastic and some are not elastic at all. Some things are
a little elastic. Let the children divide the following articles
into three classes, according to elasticity : —
(a) Stretching. — Indiarubber, cloth, leather, wire.
(1^) Pressure. — Hollow indiarubber ball, solid indiarubber
ball, marbles, ivory ball, clay, putty, sponge, cork.
(c) Bending. — Steel, tin, lead, a thin piece of wood, cane,
whalebone, springs, a strip of glass, a lead pencil or penholder,
a slate pencil.
{d) Twisting. — String, wire.
INDIARUBBER
What it is. — Indiarubber is got from the juice of some
trees growing in the East Indies [' Ittdia rubber '], Brazil, and
other hot places. Holes are bored in the roots, trunks, and
branches of these trees, and tubes or little gutters are put in.
A milky juice runs out, and is caught in pots. Illustrate by
sketch on the blackboard.
When allowed to stand the milky juice separates into two
parts — a thick, sticky part (which is the indiarubber), and a
yellowish, watery part. Often this watery part is allowed to dry
up, and the rest is sent to England. There it is passed through
a machine full of spikes which tear it to pieces. It becomes
54
Longmans' Object Lessons
hot and soft, so that it can be worked like dough and thoroughly
washed.
In some places when the juice has been got from the trees
a lump of dry clay shaped like a pear is dipped into it and then
held over a fire. ' What does the
fire make the watery part do ? ' A
skin of indiarubber is left sticking
to the clay. The dipping and drying
are done over and over again till
there is an inch or two of india-
rubber sticking to the clay. Then
the clay is broken out and the in-
diarubber is left. From its shape it
is called />ott/e n/U'er. Show a piece.
Some properties and uses. — ' Jl'e
sa'iV in the last lesson that india-
rubber ivas -V [Elastic] '■Name
things in which it is used because it
is elastic' [Braces, garters, band-
ages, elastic stockings, 'spring sides'
of boots, &c.]
If stretched and kept in cold water for some time it be-
comes inelastic. Show a piece that has been stretched and
kept in cold water for some days. It will regain its elasticity
when warmed. Before being woven into braces, &:c., the india-
rubber is made inelastic by cold.
Show that indiarubber is waterproof
Also that it is insoluble in water, but soluble in naphtha.
Articles are made waterproof by having a solution of india-
rubber spread over them. ' Name some things that are water-
proof.'
Vulcanite. — Indiarubber is ' vulcanised' by heating it with
a small quantity of sulphur. Show vulcanised rubber. It is
much more elastic than pure rubber, is not softened by hot
water [hence made into hot-water bottles], and is not stiffened
by cold.
Ebonite. — Show a comb or other article made of ebonite.
This is indiarubber greatly heated with a largequantity of sulphur,
Fig. q.
Indianihbcr 5 5
' Rubber.' — When we write with lead pencil wc leave on
the paper small grains of blacklead. When we rub these with
indiarubber little pieces of the rubber are rolled off, and the
little srains of blacklead stick to them.
B : Lessons on Common Animals
THE CAT
[Illustrations : — A cat or kitten, and a saucer of milk.]
Food. — Show cat. ' On what docs flu's cat live V ^ If u>e
did not give her any food, on what ivonld she live ? ' Emphasise
the fact that cats catch their prey alive.
Feet. — Make children count claws on fore feet [five], and
on hind feet [four], and make them observe that the former
are longer and sharper than the latter. Elicit reason. ' ]Vith
which claws does the cat catch a mouse ? ' ' Jf7iich ciaivs have
most weight on them when a cat is climbing a tree 'I '
Each claw has a sheath of thick, hard skin. Let children
see the sheath, and make the cat project and retract her claws.
Elicit use. ' JVhy must the claws he sharp ? ' ' IFhat would
happen to them when the cat ivas 7va Iking if they had no sheath?'
' IJ'hy do we cut our nails 1 ' ' How does the cat cut her
nails 2 ' ' JFho has seen a cat scratching a tree or chair ? '
' Jl'hat would a mouse do if she heard the cat coming?'
' What makes the cat aide to m.ove without making a noise ? '
Show pads under each toe and under the middle of each foot.
Teeth. — Show. Then elicit that the teeth are formed for
tearing, not for chewing.
Tongue. — Let the cat lick a child's hand. To induce her
to do so put a little milk on the hand. ' How does the tongue
feel?' Explain that the roughness is caused by little hooks
fixed all over the tongue and pointing backwards. ' Hnv does
the cat get all the meat off a bone ? '
56 Lottgmaus' Object Lessons
Let the cat lap some milk, and make the children observe
the spoon-like action of the tongue.
' ffoiv does the cat dean herself! '
Eye. — Make the children observe that the pupil in a bright
light is a narrow slit. ' IFhat is the shape of tlie pupil at night ? '
Compare admission of light through pupil to admission of
light through window. ' JfVty do we pull doivn l>li?ids when the
sun is shining ? ' ' JVhy does the cafs piipil become stnall in a
bright light 'I ' 'JJVty do we pull up blinds towards eveningV
' ]]'hy does the cafs pupil become large in a poor light 1 '
Whiskers. — Make children touch the end. They will per-
ceive that whiskers are stiff, and notice that the cat feels.
' Should ive feel if the ends of our hair were touched ? ' Elicit
use of whiskers. ' IVhy does a bli?id man hold a stick before
him ? ' ' JVhy do 'we hold our hands out when walking across a
room in the dark t ' ' JVhen. does the cat go about most 1 '
Fur. — Make children feel that the fur is thick and warm,
but not oily. Elicit that the cat is a night animal, and there-
fore needs a warm coat. ' U'hy does father oil his boots in rainy
weather V 'Jl'hy does the cat dislike 7vctV 'JJ7y does the
duck like ivet ? '
Habits. — Let the children say what they know about the
habits of the cat.
THE DOG
[Illustrate by a living clog.]
Differences between cat and dog, — Cats see their pre)', and
catch it by creeping slily up to it. Dogs smell their prey, and
catch it by running it down. Cats must therefore have good
eyes and be able to move very softly, while dogs must have
strong scent and be able to go fast and far. These differences
will account for the differences in structure between cats and
dogs.
Feet. — Make children count the claws on fore feet [five]
and on hind feet [four]. 'Jl'hat is the difference between a
dog's claws and a cafs ? ' [Dog's straighter and blunter.]
The Dog 57
' Have you ever seen a dog chase a cat ? ' ' W/iere did the cat go
to he out of the dog's reach ? ' [Tree.] ' JVhy did not the dog
follow the cat 1 '
' Have you ever seen a cat catch a mouse or a bird 1 ' ' With
what did she catch it ? ' [Claws.] ' Have you ever seen a dog
catch anything? ' ' TJ'ith what did he catch it ? '
' IVhy, then, does the cat need claws sharper and more curved
than the dog's ? '
' JVhat covers the cafs claivs ? ' ' See ivltether the dog's clajvs
are covered.' ' JJ'liy does the cat's claw need a sheath while the
dog's has none ? '
Make the children see that the dog cannot draw in his
claws ; also that his feet are not so softly padded as the cat's.
' JJ'hy does the cat need to go nio?-e softly than the dog 1 '
Teeth. — Show. '11 'hat are these sharp teeth used for?'
[Tearing.] ' Have you ever seen a dog eat a biscuit? ' ' Could
he tear a biscuit ? ' Show action of the human jaw in grinding.
Then show that the back teeth of the dog are capable of grind-
ing. IVIake children see that the human jaw moves from side
to side as well as up and down ; then tell them that the jaws
of cats and dogs can move only up and down.
Tongue. — 'How did the cat's tongue feel?' [Rough and
dry.] Make dog lick a child's hand. "■ Hoiv does the dog's
tongue feel?' [Smooth and wet.]
Eye. — ' When does a cat catch most mice ? ' [At night.]
Her eye must therefore be made to see in a bad light. ' JFhen
does a dog catch things ? ' [By day,] Question on the contrast
and the reason.
'Whiskers. — Recapitulate what was said about a cat's
whiskers [p. 56]. Then elicit that as the dog is not a night
animal, and does not have to pass through narrow holes, he
does not want feelers. Then show dog's whiskers, and make
the children observe that they are short and weak. Some
dogs seem to have hardly any.
Hair. — 'IVith what is the cat covered?' [Fur.] "^ And the
dog?' [Hair.] P'ur is the name given to the very fine, thick
hair of certain animals. If a cat be examined carefully,
' over-hair ' will be seen growing through the fur. ' Will
58
Longmans' Object Lessons
water run more easity off hair or fur ? ' ' WJio has seen a dog
fond of tJie wafer?' ' And a catV 'Why do cats dislike,
water ? '
Habits. — Let the children say what they know of the habits
of dogs generally.
Blackboard summary. — Revise the lesson thoroughly, and
place the heads of the comparison between cat and dog on the
blackboard thus : —
Cat
Dog
Prey . .
Sees, creeps
Smells, runs
Feet . . .
Claws sharp, curved
Claws bhinter, straighter
Sheath
No sheath
Soft pads
Harder pads
Teetti . .
Tearing '
Tearing and grinding
Tongue . .
Rough, dry
Smooth, wet
Eye . .
Changes shape ; for dark
One shape : for light
Whistlers .
Long and strong
Short and weak
Covering .
Fur
Hair
THE HORSE
[Illustrate by means of a good picture. If the teacher had, or could
borrow, a horse's skull it would be of great advantage.]
Head. — Long ; rather broad at top ; nose narrow.
Teeth. — ' What does a horse eat ? ' ' JVhat fart of its food
has a horse to cut 2' 'And 7v]iat part to grind or crush?'
' JJ'hat hinds of teeth 7nust it therefore have ? ' ' In ivhat part
of tlie mouth are the cutting teeth ? ' ' And the grinding teeth ? '
In front of each jaw the horse has six sharp, broad teeth
for cutting.
A little way from these there is on each side and in each
jaw a long, sharp tooth called a tusk.
' Ho7v many of you have played at horses ? ' ' How many
have had the bit iti your mouths ? ' ' Could you close your
1 The fact to be brought out is tliat cats are more purely flesh-eaters than
dogs ; the fact that even cats have teeth which naturaUsts call molars may be
ignored,
Tlie Horse 59
moutJis ? ' ' Why not ? ' Thence elicit that between the tusks
and the grinding teeth there must in the mouth of the horse be
a gap. This is called the ' bar,' and receives the bit.
Beyond the ' bar ' come the grinding teeth.
' Could a horse eat flesh ? ' ' JVhy not ? '
Neck. — Long. A horse not fed by man would live on
grass alone. ' IIo7v could it reach the grass if it had a short
neck ? ' ' JVhy, then, is a long neck tiseful V
Make children describe mane. ' When does your ?nother
put a scarf round your neck 1 ' ' Why does she put itV ' What
is the use of the mane to it horse ? '
Skin and hair.— Skin very thick ; made into leather for
soles. Hair short and iine ; grows thicker in winter. ' JFhy ? '
Sometimes clipped. ' JVhy ? ' Elicit that if the horse be
deprived by clipping of its natural covering an artificial cover-
ing should be provided.
Tail. — 'Could a fly hurt a dog or cat?' 'Why notV
[Thick hair or fur.] ' What kind of hair has a horse V 'Have
you ever seen horses stung by insects ? '
' If a fly settled on your hand, hoiv would you frighten it
away ? ' ' How does the horse, which has no hand, drive away
insects V 'Is it kind to crop a horse's tail 1 '
Feet. — 'How many toes have you V 'And a dog?' 'A
cow ?' 'A horse ? '
' With zvhat is the horse's toe covered ? ' ' What is the use of
the hoof? ' ' Why is it shod?'
Elicit that the horse's hoof corresponds to our nails ; that
therefore it has no feeling ; and that shoeing hurts a horse
only when the nails are driven into the ' quick.'
Kinds. — Dwell on the work and corresponding structure of
a few typical kinds, as
(i) The cart-horse, built for great strength, but not for
swiftness.
(2) The race-horse, built for great swiftness, but not for
strength.
(3) The hunter or carriage-horse ; intermediate.
Habits. — Let children say what they know of habits.
6o Longmans Object Lessons
THE COW
[Illustrate by good picture, blackboard sketch, and, if possible, a
cow's skull]
Where the cow lives. — 'Where does the cow mostly liveV
[In fields.] ' On what does she mostly feedt '
Feet. — '-' Witt grass groiv best in a dry field or a moist one ? '
' If you tried to walk on stilts through a moist field, what would
the stilts do ? ' [Sink in.] ' Would broad, soft shoes sink in ? '
Show picture of cow's foot ; ' cloven.' Describe. Illustrate
action by separating first and second from third and fourth
fingers.
Teeth. — ' If you iivre in a field and wanted a handful of
grass, how would you get it?' [Cut it.] 'And if you had
nothing with which to cut itV [Pluck it.] ' Could you by
listening tell 'whether I ivas cutting or plucking grass ? '
' Hotv nutny children have been near a cow feeding in a field ? '
' Did she cut or pluck the grass ? ' [Pluck it.]
Describe teeth, and, if possible, show skull. Front of lower
jaw six broad cutting teeth. Front of upper jaw no teeth,
but the gums form a kind of pad almost like indiarubber. No
teeth like the horse's tusks. Twelve grinders in each jaw.
With her long tongue the cow brings the grass between the
front teeth and the 'pad ' ; then she gives a jerk and the grass
is torn off.
Chewing the cud, — ' Who has seen a cow biting her food
when she was standing ip and eating it? ' ' IVho has seen a
cow chewing when she was lying down and not eating ? ' She
was then chewing the cud.
Explain tliat lions, tigers, and other beasts of prey are very
fond of cows. The grassy plains on which wild cows fed were
exposed. It was therefore necessary that the feeding should be
got over in a very short time. Cows therefore quickly swallowed
all the food they wanted, and then retired to some safe place to
digest it.
' What do 7ve do to food in our nuiuths ? ' [Bite it.] ' And
then?' [Swallow it.] 'Jl'here does it go then?' [Into the
77/1? Coil
6i
stomach.] There it is changed into a liquid. ' Could tue bring
the food back from our stomachs into our mouths 2 '
The cow can. She has four stomachs. She swallows the
food first ; then brings it back, chews it, and swallows it again.
Fig. io. — Stomach of cud-chewing animal [sheep]. ^, cesophagus ; ^, paunch ; c, honey-
comb ; it, manyplies ; t, true digestive stomach ; J', first part of intestine.
Neck.— Long. 'II7iv?'
Horns.— Ask questions about means of defence of familiar
animals. ' And of the cozv ? '
Skin. — Thick and strong. ' Hence made into ? '
Hair. — Rather short. Can be pierced by insects. Cows
much troubled by them in hot weather.
Tail, — 'Ifoiv does she get rid of them ? ' Tail long and tufted.
Uses. — Question about uses of cow alive and dead.
Blackboard summary. — Comparison between cow and
horse : —
Head .
Teclli .
Cud
Nccf;
Feet
Tail
Horse
C07U
No horns
Horns
Cutting teeth in both j.iws
Cutting teeth in lower jaw
only
Tusks
No tusks
Grinders
Grinders
Does not chew the cud
Chews the cud
Long
Long
Mane
No mane
One toe
Two toes (cloven)
.Shod
Not shod
All hair
Tuft of hair
62 Longmans' Object Lessons
THE ASS
Comparison with the horse. — Show pictures of horse and
ass, and ask in what way the two animals are ahke, or nearly
alike.
(i) Shape of head.
(2) Shape of legs.
(3) Feet. The ass's hoof is longer and narrower than the
horse's. Hence the ass is very sure-footed, and is used to carry
persons up mountains.
(4) The arrangement of the teeth is exactly the same in the
two animals, though this cannot be seen from the picture.
Question about the horse's teeth, and bring out the reason why
a horse can have a bit. ' Do asses have bits ? ' Then the ass's
teeth must be like the horse's.
Refer again to the two pictures, and ask in what way the
horse and the ass are unlike,
(i) Size.
(2) Colour. The horse may be black, grey, white, brown,
or bay, or may have large spots of any one of these colours,
but it never has stripes. The ass has stripes and is generally
brown, or of a brownish-grey ; a few are white, but black or
bay asses are never seen.
(3) Ears.
(4) Tail. The horse's tail has long coarse straight hairs all
over it ; the ass's tail has a tuft at the end.
(5) Mane. The ass has very little.
(6) Hair. The ass's coat is thick and warm, so that the
animal does not need a stable. It can stand wet and cold which
would be too much for a horse.
(7) The ass is, for its size, stronger than a horse.
Food. — The ass does not require such good food as the
horse. It will find enough to live on at the roadside and on
commons, and will eat thistles and other herbs that the horse
will not touch.
Habits.— The ass is generally considered stupid and obsti-
nate, but naturally it is neither. Bring out by questions that
The Ass 63
both these apparent qualities are the result of bad treatment,
and show how asses should be treated. Then describe the
quaUties of asses in the East, where they are well treated.
TJIi: SHEEP
Structure. — Show picture, and ask questions about the
more obvious points in the structure of the animal, such as its
size, the size and shape of the head, &c.
Legs. — The legs are thin but strong. Sheep living in
meadows have large, fat bodies, and cannot run very fast, but
mountain sheep are swift.
Feet. — Like a cow's, 'cloven.'
Teeth. — Also like a cow's. The sheep chews the cud.
(Fig. 10.)
Neck. — -The cow's neck is long. ' Why 1 ' ' What kind oj
neck has the sheep ? ' ' Why does the sheep not ivant a long neck V
Tail. — ' Wliat kind of tail has the sheep ? ' The sheep's tail
is not naturally so short as we generally see it, because lambs'
tails are generally cropped. ' Of ivhat use is the cow^s tail to
her 1 ' ' IVhy cannot flies sting sheep ? ' ' JVhy do sheep not
want long tails ? '
In one foreign country there is a sheep that has a long
tail covered with fat, which people like very much, so a little
two-wheeled cart is made for the tail to rest on.
Wool. — The sheep lives out-of-doors all the year round.
' JVhat kind of covering does it needV ' What are our warmest
clothes made of?' '■When does the sheep need the warmest
covering?' In summer a wild sheep sheds its wool. Tame
sheep would also shed theirs if it were not shorn off. Describe
the washing and shearing.
' Who has ever felt the wool on a sheep's back ? ' ' IVhat was
it covered ivith?' [Oil.] One would fancy that the sheep's
wool would be soaked in the rain, but it is not. ' Wliy ? '
Horns. — Ask about the way in which various animals (e.g.
the cow, horse, dog) defend themselves. '■How does the sheep
defend itself ?' Most sheep have no means of defence, though
64 Longmans' Object Lessons
some rams have horns. Ehcit the gentle, harmless nature of
the sheep.
Habits. — Question, and where necessary tell, about the
habits of the sheep, about shepherds, sheep dogs, &c.
Uses. — Question, and where necessary tell, about the uses
of the various parts of the sheep — flesh, tallow; wool, skin. The
skin of lambs is made into gloves (called 'kid ') and into parch-
ment.
THE PIG
Structure. — Show picture, and ask questions about the
more obvious points in the structure of the animal, such as its
size and shape.
Snout. — The nose is called a snout. It is long, pointed, ,
and strong. Wild pigs live in forests and woods, and feed on
acorns, beech nuts, and roots. The snout is used in digging
these out of the ground when necessary.
Pigs would spoil the farmer's fields by digging them up.
To keep them from doing this he puts iron rings into their
snouts. The rings hurt when the pigs dig, but not at other
times.
Pigs have a keen sense of smell, and are therefore used in
France to find valuable roots called truffles.
Teeth. — A pig has teeth for cutting, tearing, and grinding.
It can therefore eat almost any kind of food.
Boars, especially wild boars, have two large tusks.
Food. — '■On what do pigs feed V Question out that pigs
will eat many refuse substances, and that valuable flesh is
therefore obtained at a small cost.
Skin. — The skin is very strong and thick. It is made into
saddles and strong purses.
Hair. — ' Who has seen a saddle 1 ' ' J-Vho has noticed little
holes in it?' A bristle grew in each of these holes.
Pigs have no hair, but all have bristles — some more, some
less. These bristles are made into paint-brushes, and are used
by shoemakers.
Tail. — The tail is very short and often curly. ' Of -what
The Pig 65
use are the tails of cows and horses to t/ieiii ? ' ' JP'hat hind of
skin have pigs ? ' ' JV/iy do they not need long tails 1 '
Feet. — The feet of the pig are cloven. '■Name other
animals with cloven feet 7 ' ' Ifo7i' many of these animals chnv
the cudV '■Does the pig clieiv the cud?' The Jews were
allowed to eat the flesh of any animal that had cloven feet and
chewed the cud. ' JJ'ere they allowed to eat pigs ? '
Flesh. — The flesh of the pig when fresh is called pork.
When smoked or otherwise ' cured ' it is called bacon. The
inside fat is called lard.
Habits.— Question about the habits, and show that the
pig is not naturally so dirty> greedy, and stupid as is often
supposed.
THE MOUSE
[Illustrate by a dead mouse. A living one in a trap would also be
useful.]
Some habits, — Question on the habits of the mouse, and
emphasise the following facts : —
(i) It gnaws through boards.
(2) Eats cheese, tallow, fat, &c., but nothing that needs
tearing.
(3) Passes through holes.
(4) Is out by night.
Teeth. — 'How 7i of a plant. Show roots. Cut to show
structure. It is very nourishing, but has a strong smell and
pungent taste.
COCOA
Cocoa and cocoa-nut. — Cocoa and the cocoa nut grow on
two trees entirely different. The cocoa nut is the fruit of a
palm ; the cocoa bean (of which cocoa and chocolate are made)
is the seed contained in the fruit of a tree something like a
cherry tree. The proper name is cacao.'
Where grown.— The cocoa tree grows best in countries
1 The botanical name is thtiohroma cacao. Thcol'roiiia means ' food for the
gods,'
76 Longmans Object Lessons
which nre very hot and moist — such as Ecuador, Trinidad,
Venezuela (Caracas), and Northern Brazil.
The tree. — The tree is from 15 feet to 20 feet high. Make
concrete. Its trunk is straight and slender. The leaves are
much like those of a cherry tree. The flower is of a reddish-
yellow and without scent. The pod resembles a cucumber in
shape and size, and, when unripe, in colour also. When ripe it
is red. It contains from thirty to a hundred seeds something
like almonds. These are the cocoa beans.
Cultivation. — The ground being thoroughly cleared of all
weeds and stumps, the best and largest beans are thrown into
water. Those that float are useless. Those that sink are kept
in the water till they sprout. They are then planted in holes
about 20 feet apart. As they grow the)' nmst be protected
from the sun. The tree is at its best when about eight years
old.
Gathering. — The fruit is ripe when the beans rattle in the
pod. It is gathered twice a year, the gathering being done by
hand.
Preparation. —After being taken out of the pods the beans
are buried under a heap of green leaves. This soon becomes
so hot that the hand cannot be held in it, and the beans
ferment. The fermentation takes away a bitter taste from the
beans and keeps them from growing musty. After being fer-
mented the beans are roasted, and then bruised to loosen the
skins. When these have been removed by fanning we have the
' cocoa nibs ' sold in the shops.
The beans are very oily, and when ground make a kind of
paste. When this has first been allowed to harden and then
been cut into thin slices it forms flaked cocoa.
The oil is hard to digest, so it is removed when the best
' soluble ' cocoas are made.
The oil is made into cocoa butter, which may be kept for
any length of time without going bad.
Cocoa made into a paste, with sugar and some flavouring
added, becomes chocolate.
Coffee 77
COFFEE
[There ought to be no difficulty in procuring unroasted and
roasted coffee 'beans' and ground coffee to illustrate this lesson.
There maybe some difficulty in getting a good picture of the tree.]
What it is. — Coffee is a part of the berry or fruit of a tree.
Where grown. — This tree grew first in Abyssinia. Then
it was grown in Arabia and Persia, and now it is grown in most
hot countries where the soil is suitable — such as Jamaica, Brazil,
Ceylon, Java, Sumatra, &c.
The tree. — The tree is an evergreen, with leaves much like
those of the laurel. If allowed to grow it would be as big as
a large apple tree (about 20 feet high), but it is kept at a height
of 6 or 8 feet. The flower is of a beautiful white, with a strong,
sweet smell.
The berry. — When the flowers fade the berries come in their
place. Each berry, when ripe, is about the size and nearly the
colour of a cherry. After removing the fleshy outside we come
to a kind of skin, inside which are two ' beans ' face to face.
Show. The beans are on one side flat with a deep ridge, and
on the other side curved.
Gathering and preparation. — When ripe, the fruit is
gathered, or shaken on cloths spread under the trees. The
berries are passed between rollers which are close enough
together to crush the fleshy part, but not close enough to crush
the beans.
After being crushed the pulp is washed away, and the
berries, still in their skin, are set to dry in the sun.
■When dry they are passed between rollers which break the
skin. The broken skin is blown away, and the beans are
sorted and packed.
Roasting. —Show unroasted beans and roasted. Ask for
the difference in aijpearance, taste, and smell. The unroasted
beans are greenish in colour, and almost wanting in the peculiar
taste and smell of coffee. They are roasted by being placed in
an iron vessel which is turned round ff/^i'.?'] over a fire.
78 Longmans' Object Lessons
The roasting should take place as short a time as possible
before the coffee is wanted.
Grinding, — This also applies to the grinding. Describe
the grinding.
ORANGES AND LEMONS
Orange. — Where grown. — The orange is believed to be a
native of China, but it is now grown in all parts of the world
having a suitable climate. Those imported to Britain come
mostly from Spain, Malta, St. Michael (in the Azores) and
Italy. The United States grow a large number in Florida and
California, and also import many from the AVest Indies.
Kinds. — The most important are the mandarin or China
orange, the Maltese, the St. Michael's, and the blood orange.
[' Why so called 1 '] The Seville orange has a bitter taste, and
is therefore not eaten like other oranges, but it is very useful.
From its flowers we get orange-flower water and an oil employed
in making eau de Cologne, while the rind is cut up for mar-
malade.
The tree. — The orange tree is small. It has dark-green
leaves dotted over with little points filled with oil. Most of the
children have seen the pretty white flower in the ' orange
blossoms ' worn by brides. AV'hen ripe the oranges are gathered,
wrapped in maize leaves, and packed in boxes.
Lemon. — Compare the orange and the lemon. They belong
to the same family of plants. The lemon is a native of the
north of India, whence it was introduced to the south of
PZurope. Many of those imported into Britain come from
Italy, Spain, and Portugal. Lemon juice is made into citric
acid, which is much used in the preparation of effervescing
beverages. The peel is used fresh in confectionery, &c., and
candied it is used in puddings.
Lime. — The lime belongs to the same family. It is grown
for its juice.
Mtistard 79
MUSTARD
Where grown. — Mustard grows wild in nearly every part of
the British Isles, but it is cultivated chiefly in the counties of
York and Durham.
Two kinds. — There are two chief kinds, called, from the
colour of the seed, the white and the black. The white grows
to a height of about 2 feet, the stem and leaves are nearly
smooth, and the seed is of a pale colour. The black is about
3 feet in height, the stem and lower leaves are rough, and the
seed is of a dark-brown colour.
Cultivation. — The ground is prepared as for corn. The
seed is sown in spring, broadcast or by drill. When the plants
are a few inches in height they are thinned by hoeing. In
summer they are covered with bright yellow flowers, which give
place to the pods containing the seeds.
Preparation. — Like wheat, barley, oats, rice, &c., the mus-
tard seed has an outside husk or skin. Formerly this was
ground up with the flour, but now it is generally separated as
the bran of wheat is. The mustard sold in the shops often
consists of more than flour of mustard — turmeric (the root of a
plant somewhat like ginger) being added to make it yellow,
corn-flour to make it bulky, and capsicum (the fruit of the
plant from which we get cayenne pepper) to make it hotter.
Oil and cake. — Instead of being ground mustard-seed is
sometimes pressed, when a good deal of oil runs out of it.
This oil is used to rub persons suffering from rheumatism.
When as much oil as possible has been pressed out of the seeds
they are made into oil-cake, which is used as food for cattle.'
The same is done with the seeds of the flax after linseed oil
has been pressed out of them.
1 Oil-cake might seem too hot for food, l3ut it shou'd Ije remembered that
the pungent properties of mustard are due to an acrid volatile oil which does
not exist ready formed in the seeds, but which is produced from rayronic acid
by fermKQtation when the mustard flour is moistened \\\t\\ water.
8o Longmans' Object Lessons
THE OAK
[Provide a picture of the oak ; also specimens of the leaves,
acorns, galls, and timber.]
General appearance. — The oak is a tree with a thick trunk
and large spreading branches.
Roots. — Elicit that if such a tree were not held very firmly
in the ground it would be blown down by storms, and that
therefore it must have big, strong roots. When the tree is old
some of these grow above ground. By referring to the way in
which the roots of a plant in a pot suck up moisture, elicit
that the oak feeds (partly) by its roots, and that for this reason
also they must be big.
Timber. — The trunk grows outward, each year's growth
making a ring round the older wood. Show the rings in a
transverse section. The oak will live for hundreds of years.
The timber is very hard. Hence it is used for making things
which must be strong or stand wear. Name some things made
of oak. Formerly nearly all ships were made of it, both because
it is strong and will keep out water.
Bark. — Show. When the trees are felled the bark is stripped
off and sold to tanners. It contains something called tannin,
which changes skins into leather.
Acorns. — Show. They are the fruit of the oak, and if they
are planted oaks will grow from them. Uncivilised people
often eat acorns, but as they have a bitter taste, civilised people,
having other articles of food for themselves, leave the acorns to
pigs, deer, squirrels, rats, mice, and birds.
Galls. — Show. There is an insect which makes a little hole
in the skin of the leaves and stalks and lays an egg there. Part
of the juice of the leaf hardens into little balls around the egg.
These are about as big as a marble, green at first, but brown
when dry. They are called oak-galls, or gall-tints, and are used
in making ink.
SECOND YEAR
A : Lessons on Common Properties
HARD AND SOFT SUBSTANCES
Soft and hard.— Provide as many substances of different
degrees of hardness as may be readily procured, such as soap,
putty, clay, brick, bone, ivory, slate, chalk, indiarubber, wood
of various kinds, glass, emery-paper, lead, zinc, copper, tin,
iron, steel (and other metals if possible). Let the children try
how many of these they can scratch with their finger-nails.
Place these substances together as soft. The rest may be con-
sidered hard.
Comparative hardness. — By continued experiment make
quite clear that the harder of two substances will scratch the
other. Applying this test, arrange in order of hardness all
the substances provided for illustration, and let the children
note carefully the relative positions of the more important ones.
Omitting the emery-paper, glass and steel will stand highest.'
Diamond. — Let a child try to make a mark on the glass
with the point of a steel knife. ' ]Vliat does tJiat shoiv about the
hardness of t lie glass ? ' If possible, borrow a glazier's diamond,
and let a child scratch the glass with it. If one cannot be got
ask what a glazier cuts glass with. ' IVhat does that show about
the hardness of tlie diamond ? ' Diamond is the hardest sub-
stance. It can be polished only by rubbing with diamond dust,
and it has lately been used for boring very hard rocks.
Emery, — Emery is a mineral.^ It is made into a very fine
1 Order of harifni-ss of mi-fats.— S^&:\, iion, silver, copper, platinum, gold,
tin, bismuth, zinc, lead.
'^ It gets its name from being found at Cape Emeri in the island of Naxos.
G
82 Longmans' Object Lessons
powder and spread on glued paper. Elicit that as it is used to
polish steel (which it does by rubbing off little bits) it must be
harder than steel.
Steel. — Steel is the hardest of metals. Get the children to
name various tools made of steel, and to see that these would
be useless unless very hard. But steel may be made hard or
soft. Provide a piece of steel such as a big needle. Prove its
hardness by showing that a file will not mark it. Warm it, and
let it cool slowly, and with the file prove that it is now soft.
Show that it will bend. Warm it again, and when it is red-hot
cool it instantly by plunging it into cold water. Now prove
that it is hard and britde.
Alloys. — '■What are our coins made of?' 'Jl'/iat ivould
happen to them if they were soft 2' Gold, silver, and copper are
softer than iron. To keep them from wearing out quickly they
are mixed with harder metals, gold and silver with copper, and
copper with tin and zinc' Brass is a mixture of copper and
zinc ; pewter of tin and lead ; type-metal (used also for shot
and bullets) of lead and antimony.
FUSION
Solid and Liquid. — See that the children can distinguish
between solids and liquids, and ask about each of the sub-
stances produced whether it is a solid or a liquid.
Heat changes some solids into liquids.— Show a piece of
ice or of butter, AVarm it in an iron spoon, watch-glass, or
evaporating-dish. ' JJ'hat change has tahen place in it ? ' ' Jl'/iat
caused it to cJiange from a solid into a liquid V
Perform the same experiment with other substances, such
as tallow, wax, lead (which should be melted in an iron spoon).
Emphasise the fact that each is at first a solid, and is changed
by heat into a liquid.
All solids do not melt with the same heat. — If a piece of
1 ' Gold ' coins contain ii parts gold, i copper,
' Silver ' coins contain 92.7 parts silver, 7J. copper,
' Bronze ' coins contain 95 parts copper, 4 tin, i zinc'
Fusion 83
ice has been provided, let a child hold it in his hand. The
heat of the hand is enough to melt it. If no ice has been pro-
vided, let a child melt a small piece of butter by holding it
between finger and thumb.
Let the same child try to melt the lead in the same way.
Hence elicit the fact that heat which would melt the ice (or
butter) will not melt the lead.
If there is a fire, put the poker or any other piece of iron
in it. If there is no fire, hold a piece of iron wire in the flame
of a spirit-lamp or Bunsen burner. The iron will not melt,
but it becomes soft. By questioning about furnaces bring out
the fact that at a very great heat iron will melt.
Show some mercury. '■Is this a solid or a liquid V It is
the metal that melts most easily. Only in a very, very great
cold will it keep solid. '
The heat of fire will not melt platinum. Show. Hence
vessels for melting gold and silver are made out of platinum.
No one has yet succeeded in melting charcoal. Show.
Some substances burn instead of melting-. — Bring this out
by trying to melt paper, wood, coal, &c. That fusion and not
combustion would take place if oxygen were kept from these
substances may be ignored at this stage.
DUCTILITY, TENACITY, AND MALLEABILITY
Ductility. — Hold a glass rod by the ends, and warm the
middle in the flame of a spirit-lamp or Bunsen burner. (Fig.
41). Show that when the glass has been softened it can be
drawn out into a very thin ' wire.'
Perform the same experiment with sealing-wax.
Then show various metal wires and explain the method of
making them. The metal is first made into rods about ^ inch
' The melting-point is — 38-8'= Cent. The following are arranged in the
order of the melting-point : — Mercury, ice, butter, phosphorus, white wax,
sulphur, tin, lead, zinc, silver, gold, iron.
G 2
84
Lovgiuans' Object Lessons
thick by being drawn while red-hot between grooved rollers.
[There is no need to give the diameter of the rods, but show
a piece of twine or a knitting-needle of the proper size.] The
rods when cold are pulled through a draw-plate. The draw-
plate is made of hard steel, and has a large number of holes
growing gradually smaller and smaller. The rods are drawn
through the largest hole first, then through the next, &c., till
small enough.
Fig. 12.— a Draw-plate i^f).
Some metals cannot be made into very fine wire, as they
break when being pulled through the smaller holes of the
draw-plate. Lead breaks most, and platinum least, easily.
Platinum has been drawn so fine that over 33,000 pieces would
lie side by side in an inch. Show an inch.
Some of the finest wire in common use is the steel
wire woven to form the gauze of safety lamps. Show wire
gauze.'
Tenacity. — The best way to illustrate tenacity is to have
thin wires of the same diameter but of different metals, and to
suspend weights till the breaking-point is reached, making the
children note the weight in each case. Where this cannot be
done, let the same child break successive wires and note the
comparative difficulty. Glass and sealing-wax will break very
easily, lead less easily ; the hardest of all to break is steel,
and the next hardest ordinary iron. Hence the cables of great
ships and the ropes for suspension bridges are made of steel
wire.
1 The order of ductilily (as
copper, gold, zinc, tin, lead.
;iven by Ganot) is platinum, silver,
Ductility, Tenacity, and Malleability 8 5
Malleability. — Using a flat piece of iron as an anvil, show
that lead can be hammered out. Similarly hammer out a
piece of copper wire. Then try to hammer out a piece of iron.
By reference to a blacksmith elicit that iron can be easily
hammered out when heated.
Some metals can be beaten very thin when cold. Gold
can be beaten thinnest of all metals. Question about gilding,
and show gold-leaf To make this the gold is first pressed in
a rolling-mill. Illustrate by two cotton-reels or compare to a
mangle. By rolling, the gold is made into plates so thin that
twenty-five of them would make an inch — in other words, the
plates are about as thick as two playing-cards. These are
then beaten thinner with a hammer, cut, and beaten again and
again. Show with the lead or copper that when thin metal is
hammered it gets torn. To prevent this the gold is placed
between sheets of goldbeaters' skin. Show. Thus beaten,
the gold can be made so thin that 300,000 leaves would make
only an inch. Show an inch, and show how many leaves of a
paper book make an inch.
Dutch metal, a kind of brass, can also be hammered out
very thin. Show various metal foils and ask about their
uses.
The terms. — Anything which can be drawn out into wire
is said to be ductile ; anything that is dilTicult to break is said
to be tenacious ; and anything that can be hammered out is
said to be malleable.
86 Longmans Object Lessons
In recapitulation produce wood, glass, sealing-wax, metals,
&c., and ask to what degree they possess each of the properties
dealt with in the lesson.
IRON 1
Iron is hard and strong'. — Get from the children and write
on the blackboard the names of a few things made of iron,
such as ships, bridges, pillars, engines, &c. ' Why would not
lead do for these things 1 ' Iron is used because it is hard and
strong (or tenacious).
Question briefly about the test of comparative hardness
given in a former lesson, and apply it to show that iron is the
hardest of the metals.
Similarly revise the lesson on Tenacity.
Iron can be welded. — Heat two pieces of iron wire and
weld them. Question about the work of a blacksmith. Iron
is one of the very few metals which can be joined (or welded).
Show how much less useful iron would be if it could not be
welded.
Iron can be hammered out. — Show piece of sheet iron, and
get from the children names of things made out of it.
Iron can be drawn out. — Briefly revise lesson on Ductility.
Show iron wire, and get names of things, great and small, made
of it.
Iron ore. — In many parts of the country large quantities of
a kind of stone called iron ore are found. Show. This is
generally a mixture of iron, clay, and lime.
Furnace. — Show a picture of a furnace. By reference to
the lesson on Fusion remind the class that at a very great heat
iron will melt. ' If you -ivant the fire at home to light up quickly
■what do you use ? ' ' Jl'hat comes out of the hello'ws ? ' To get
in the furnace the great heat needed to melt iron a blast of
air is kept passing through.
1 This and the lessons immediately following it are intended partly to apply
to special cases the preceding lessons on properties, and partly to gi\'e some
information about the origin and preparation of the common metals.
trdn
8;
Into the furnace a mixture of iron ore, limestone, and
coke is thrown. The hme, the coke, and the coal take away
from the iron ore nearly everything
except the iron. Into a tumbler of
water drop a piece of wood and a
piece of iron. ' Why does the iron
sink ivhile t)ie wood floats ? ' ' What
will the iron in the furnace do when
it is melted 1 ' [Sink to the bot-
tom.] ' JVhy ? ' A hole is then
opened near the bottom of the fur-
nace, and the iron runs out into
grooves made in sand. Illustrate
by a sketch on the blackboard.
This iron is called cast iron. Show
some cast iron. Ask the children
to name things made of it. By
exhibiting a broken piece, or by breaking, show that it is
brittle.
Wrought iron. — Cast iron is brittle because it contains a
good deal of charcoal. Show. To get rid of the charcoal a
draught of very hot air is passed over the melted cast iron,
which is also stirred or puddled. In this way the charcoal is
burnt off and wrought iron is left. This is very tough, and
can, when cold, be drawn into wire, and hammered into any
shape when heated.
Steel. — Steel contains less charcoal than cast iron and more
than wrought iron. It can be made hard or soft by tempering.
Repeat experiment from the lesson on Hard and Soft Sub-
stances.
G. 14. — Section of a Blast Furnace.
LEAD
Properties and uses.— Let the children compare the weight
of lead with the weight of other substances. They will dis-
cover that it is heavy.
Let them scratch it with their nails. It is soft. It makes
a mark — that is, it is so soft that little bits of it come off
88 Longmans' Object Lessons
when rubbed— on paper. The ' blacklead ' of which pencils
are made is not a kind of lead.
Lead melts easily. Show this by melting some in an iron
spoon. Because lead is heavy and melts easily it is used for
shot. Show some. The melted lead is poured into a vessel
with holes in the bottom [' Why ? '], and allowed to fall a great
height ['ff'7y?'] into cold water. 'Why?' 'Who has seen a
shot-tower 1 ' ' Why would it not do to have soft shot 1 ' Hammer
shot and small pieces of lead to show comparative hardness.
The shot is made hard by mixing a little arsenic with the lead.
Show solder. Question about its use, and elicit that it must
melt easily. Lead melts easily, but is too soft for solder, which
is an alloy of lead and tin.
Show the lead lining of tea-chests. The Chinese make
this by pouring melted lead on one smooth flat stone and
placing another upon it.
Ijead is malleaHe. Show this. Show a piece of ' milled '
sheet lead. This could be made by hammering. It is made
by being passed between rollers. Illustrate.
Lead i?, flexible. Show that sheet lead and lead piping can
be easily bent, and that they are not elastic. Bring out by
questions that lead is adapted by its flexibility for use on roofs,
as lining of cisterns, for gas and water pipes, &c.
Pure lead is bright. Cut a piece, and contrast the colour
thus exposed with the dull grey surrounding it. This grey is a
kind of rust, but as it does not dissolve in ordinary water there
is little danger in using lead for the lining of cisterns.
Lead ore. — The most common lead ore consists chiefly of
a mixture of lead and sulphur. This is found in many parts
of the British Islands.
Roasting'. — The ore is first picked, broken, and washed to
separate the earthy parts. The remainder is then roasted in
a kind of long, low oven to burn away the sulphur.
Smelting. — The roasted ore is placed in a furnace and
melted. When melted, the lead sinks to the bottom [' Why ? '],
and the impurities rising to the top can be skimmed off. The
lead is run into moulds, and is cviW&A pig lead.
Copper . 89
COPPER
Properties and uses. — Produce some copper wire. Copper
can be drawn out into finer wire than any ordinary metal,
except gold, silver, and iron. Prove by experiment that copper
wire is very tenacious (iron alone is more tenacious) and
flexible.
Hammer out a piece of copper wire to show that the sub-
stance is malleable. When hammered or rolled out into sheets
it is very elastic. Sheet copper is used for scuttles, kettles, &c.
Also used to cover those parts of a ship under water, to
protect the wood from creatures living in the sea.
Copper is a loud-sounding metal — hence used for gongs,
bells, &c.
Telegraph wires are generally made of copper. [The reason
— viz. that copper is of all metals the best conductor of elec-
tricity — need not be given at this stage.]
Copper rust is green. Show. It is very poisonous. As
sour fruit, vinegar, and other things cause copper to rust, the
metal must not be made into any vessel used in cooking.
Copper ore. — The most common ore of copper is a mixture
of sulphur, copper, and iron. It is found in Cornwall, Devon,
Anglesey, Westmoreland, Cumberland, &c. Show.
Roasting and smelting. — The process of getting pure
copper from the ore is too long and complicated to be described
to young children. It consists of a series of roastings and
smeltings.
Alloys. — Brass [Show] is an alloy of about two parts of
copper to one of zinc. The two metals are melted and mixed,
and then cast into plates. Brass is malleable and ductile when
cold. It melts more easily than copper, can be polished
brightly, and does not rust quickly. Made into pins.
Bronze. — Copper and tin. Very hard ; formerly used for
weapons. Now used for statues. Also for coins.
Dutch metal. — Show. Eleven parts of copper and two of
zinc. Almost as malleable and bright as gold. Used for
'gilding' cheap frames, &c.
90 Longmans^ Object Lessons
TIN
Properties and uses. — Tin is of all common metals the
easiest to melt. It will melt in the flame of a candle. [Melt
some. If pure tin cannot be obtained, melt some tinfoil.] Tin,
therefore, cannot be employed in any articles to be exposed to
great heat.
Tin is very malleable. Show tinfoil. A thousand sheets of
the thinnest foil would be only an inch thick. Ask for the
names of things packed in tinfoil. ' Why is the foil superior to
paper 1 ' [Not being porous or absorbent it keeps out damp,
and keeps in the aroma of the articles packed in it.]
Tin itoes jwt rust easily. Show a piece of rusty iron.
^]Vhat caused it to rust V [The damp air.] Revise that part
of the lesson on Copper which dealt with copper rust. Cooking
vessels made of iron or copper are therefore lined with tin.
^Vhat is often familiarly called tin is really tinplate. This
is tinned iron. Thin sheets of iron, first thoroughly cleaned,
are dipped in melted tin. ' ]] hy V It would be useful to have
frying-pans and gridirons tinned. ' ]]liy are they not ? ' [The
heat to which they are exposed would melt the tin,]
Tin is soft. Show that it can be cut with a knife.
It ca/i he bent, but is inelastic. Show.
It has /////(' tenacity, therefore not used for wire.
Alloys. — Pewter is an alloy of tin and lead. [The better
kinds have antimony and copper instead of lead.] ^Uses and
properties ? '
Britannia metal, a superior kind of pewter. 'Uses?'
Bell-metal and bronze, chiefly copper with some tin.
Solder, tin and lead. ' Uses and properties ? '
Manufacture. — Tin ore is found in Cornwall. [If possible
show some.] It is first crushed and then washed. Much of
the dirt passes a«-ay with the water. The ore is then roasted,
like copper ore, to drive away any sulphur which there may be
in it. Mixed with small coal and slaked lime, and strongly
heated, it gets rid of most of the remaining impurities. It is then
melted, and the impurities rise to the surface and are skimmed off.
Zinc
ZINC
91
Properties and uses. — Show a piece that has been exposed
to the air for some time. It is dull. A little scratching will
expose a bright surface. Only a very thin coat of rust forms
on it, and this is not poisonous.
When cold, zinc is not malleable ; but when heated, it can
be hammered or rolled out into sheets. These are flexible,
and, as zinc is lighter than lead, it is used for roofs, gutters,
pipes, &c.
Zinc is hard. Show that of the common metals it comes
next to iron and copper in hardness. For the properties
named it is used to make vessels for holding water — baths,
pans, cans, &:c. The fact that its rust is not poisonous also
leads to its use in cisterns, but it is said to give a taste to the
water.
Its hardness and indisposition to rust cause it to be made
into saws for cutting blocks of salt. Elicit that iron saAvs
would rust.
Zinc and lead make a very ductile alloy. This wire is
cheaper, softer, and more flexible than iron or copper wire.
Used by gardeners for tying trees and shrubs and fastening
labels. ' Why .? ' ' Why would not twine doV ' Why ivould
not iron wire do 1 '
Just as iron for saucepans, &c., is coated with tin to
prevent rust, iron for roofs, fences, and the walls of temporary
buildings is coated with zinc. The iron is dipped into melted
zinc. The wrinkling (corrugating) gives strength. Refer to
some place in the neighbourhood where galvanised iron (as it
is called) is in use.
Preparation. — The British Islands are not rich in zinc.
Much of the ore we use is imported from Spain and Italy.
The ore is first roasted to drive off the sulphur. It is then
mixed with coal or charcoal and placed in large earthenware
jars in a furnace. From each jar an iron tube passes into a
vessel containing cold water. The zinc after melting passes
through the tube as vapour, and is condensed in the water.
92 Longmans' Object Lessons
FINS
Properties. — Provide : —
(i) A piece of thick wire. [Part of a knitting-needle
will do.]
(2) A crooked pin.
(3) A pointless pin. [Cut the point off with a pair of
pincers.]
(4) A headless pin. [Cut off head with pincers.]
(5) A piece of rough wire. Ask children to fasten pieces
of stuff with these things, and thus elicit that a pin must be
(i) Thin.
(2) Straight.
(3) Sharp.
(4) Headed.
(5) Smooth.
Manufacture. — (i) Show that a needle is hard, and will
break if bent. Show that a pin is soft, and will not break if
bent. ' JVhat are needles niaele of?'' [Steel jvire.] ' What are
pins made of V [Brass wire.] Show.
(2) Revise what was said about wire-making in the lesson
on Ductility, and add that brass wire of the proper thickness
is supplied to the pin-maker.
(3) Cleaning. — Pour a few drops of sulphuric acid into a
little water. Place a penny in the mixture, and then rub it. It
will become as bright as when new. The brass wire is cleaned
in much the same way. ' Why must it be cleaned? '
(4) Straightening. — ' IFhy must fins be straight?' The
wire is straightened by being drawn between six or seven
smooth iron pegs set upright in a table nearly in a line and
some distance apart. The wire is made to pass on the left of
one peg, the right of the next, (S;c. Illustrate by drawing a
piece of wire between some nails fixed in a piece of wood.
(5) Cutting a?id sharpening. — The wire is cut into lengths
for six pins. Illustrate with a piece of brass wire. Both ends
are sharpened by being ground first on a steel wheel cut like a
file [Show a file, and how it acts], and then on a grindstone.
Pius
93
Lengths for two pins are cut off, and the ends are again
sharpened. Two more lengths are cut off, and when the
remaining ends are sharpened the wire is cut in the middle.
(6) Heading. — Smaller and softer wire is taken and wound
spirally round a long piece of stiff wire of the same diameter
as the pins. The coil is then cut up into bits containing two or
three turns, each bit to form one head. Pins are then dipped
into a heap of heads till each pin has taken up one. The pins
are then placed point down in holes in a piece of steel, and
the head is hammered on.
(7) Tinning. — Refer to the tinning of iron for tinplate,
and the zincing of iron for galvanised iron. Pins are tinned
by being dipped into melted tin. ' Why are they tinned V
(8) Drying a]id polishing. — The pins are dried and polished
by being turned round in a barrel containing bran.
(9) Papering. — Show ■ a paper of pins, and explain the
papering.
PENS
[Specimens showing every stage in the process of pen-making^
may sometimes be obtained through the generosity of manufac-
turers, and can always be bought from some of the school pub-
lishers. These specimens form the best possible illustration of a
lesson on Pens — indeed, they almost form a lesson in themsehes.]
Material. — Pens are made of ' ribbons ' of the best steel.
Cleaning. — ^ How was the brass wire used in making pins
cleaned ? ' The steel for pens is cleaned in the same way.
Eolling. — The ribbons are pas,sed between steel rollers till
they are of the right thickness. Compare to a mangle, and
illustrate with two cotton-reels.
Blanks. — pjy means of a punch pieces (called 'blanks') are cut
out. These are of the same shape as a pen would be if flattened out.
Piercing. — Show the hole at the top of the slit. This is
punched out, and the side slits, if any [Show pens with some],
are cut at the same time.
Softening, — The next processes are marking and ' dishing '
94 Longmans' Object Lessons
or curving ; but the steel is at this stage too hard for either,
and it must therefore be softened. Refer to the lesson on Hard
and Soft Substances, and ask how steel is softened. The
' blanks ' are placed in an iron box, heated, and allowed to cool
slowly.
Marking. — Show the maker's name and other marks.
These are stamped on the soft steel.
' Dishing.' — The ' blanks ' are then curved by being pressed
into grooves. Illustrate by pressing a piece of thick paper into
a groove.
Hardening, — The pens are then hardened. Again refer to
lesson on Hard and Soft Substances. The pens are hardened
by being heated and plunged into oil.
Tempering. — Show that a pen is elastic, and that an in-
elastic pen would be useless. The desired elasticity is given
by tempering. The steel is heated (but not made red-hot), and
is allowed to cool.
Grinding. — The pen is now properly pointed by grinding
on a wheel made of emery powder and clay baked together.
Refer to ' Emery ' in the lesson on Hard and Soft Substances.
Slitting. — By means of a quill show that a pen which has
no slit will not write. Each pen is laid on a chisel the edge of
which reaches from the point to the hole. A similar chisel is
forced down. The two meet, and the pen is slit.
Heating. — The pens are coloured by heating. The shade
of colour depends on the amount of heat employed.
B : Lessons on Animals
THE LION AND TIIE TIGER
Revise rapidly lesson on the Cat. Treat the lion and the
tiger as in structure and habits very like large cats.
The lion. — Found in Asia and Africa.
Size. — Show picture. The lion is about 4 feet in height at
the shoulder. Show 4 feet.
The Lion and the Tis'ei'
95
Colour. — Tawny ; the same colour as a mastiff. This is the
colour of the sandy deserts in which the hon hves. EHcit that
Fig. 15. Skull of Lion.
the animal can therefore hardly be distinguished from sur-
rounding objects by day, and not at all by night.
Fic. 16.
Mane. — The lion"when full grown has a thick, shaggy mane.
The lioness has no mane.
g6 Longmans^ Object Lessons
Tail. — The lion differs from the cat in having a tuft at the
end of the tail.
Climbing. — The lion also differs from the cat in being
unable to climb.
Teeth as in the cat. Draw teeth, and show that they are
formed for tearing alone. Even the back teeth are unfit for
grinding, and as the lion's jaws move only up and down, grind-
ing would be impossible with any teeth. (Fig. 15).
Whiskers, feet (with pads), dmvs (with sheaths), and tongue
as in the cat.
Prey. — The lion, like the cat, does not chase its prey. It
creeps silently up until about 20 feet off, and then springs.
The lion can carry off a horse or a cow as easily as a cat can
carry off a mouse.
The tiger. — Found only in jungles in certain parts of Asia.
Size. — Show pictures of lion and tiger, and ask children to
compare the two animals. The lion is a little taller, but cer-
tainly not stronger, fiercer, or more cunning.
Colour. — Bright gold with black stripes. Elicit, as in the
case of the lion, that this makes the animal hard to distinguish,
the yellow being of the same colour as the tall grass amidst
which the tiger lives, and the black stripes like the shadows.
Structure. — There is no tuft to the tiger's tail. In other
respects it resembles the lion.
Hunting. — Tigers often lie in wait for men and kill many.
They are therefore hunted more steadily than lions. Describe
methods : (i) Traps ; (2) By men on elephants.
THE WOLF AND THE JACKAL
Revise rapidly the lesson on the Dog, and dwell on the fact
that in structure and haljits the wolf and the jackal are really
only fierce, wild dogs.
The wolf. — Found in nearly every part of the world, hot or
cold. Wolves were once common in the British Isles.
Size. — Show picture. The wolf is about 2^ feet high at the
shoulder, and about 35 feet long from the muzzle to the root
The Wolf and tlic Jackal 97
of the tail. Show these measurements, and compare the wolf
in size to a St. Bernard or big Newfoundland dog. The tail
(which is bushy like a collie's) is about i^ foot long.
Structure. — The muzzle also resembles a collie's.
The ears are pointed and upright.
The eyes are set slantingly.
The teeth are like a dog's. The bite of the wolf differs
from that of the cat tribe. The lion and the tiger seize their
prey and then drag it to the ground. The wolf is not strong
enough for this, so it gives a large number of sharp, quick,
snapping bites, the teeth meeting each time in the flesh. In
this way the animal attacked soon falls from loss of blood.
TIabits. — By reference to a fo.x-hunt elicit that dogs chase
their prey in packs. Wolves do the same. Hardly any crea-
ture is too large for them to attack. Going at a long, swinging
gallop they will follow for hours the creature they have chosen.
^^Tlen they overtake it they fall upon it from all sides, and soon
bring it to the ground. They will devour even a horse in two
or three minutes, and then they often fight among themselves,
eating up those of their number which are hurt or killed.
Wolves are as cunning as foxes. Tell some story to illus-
trate this.
Wolves are very fierce and savage, but when caught very
young they can be tamed, and they then become as friendly as
dogs.
When alone a wolf is cowardly, never, except when half mad
with hunger, daring to attack a man.
The jackal. — Where fcund. — The two most common kinds
of jackals are found, one in India, and the other in South
Africa.
Structu7-e. — The jackal differs from dogs and wolves ir.
having a very long, pointed muzzle. It is also smaller than the
wolf, being only about 18 inches high at the shoulder. Show
this, and compare the jackal to the collie in size.
Habits. — Jackals are rather cowardly. Like wolves, they
hunt in packs, and united they can pull down a deer. They
search for food at night, making a hideous yell.
The jackal has been called the lion's provider, from the
H
98
Longmans Object Lessons
belief that it finds tlic prey which the lion kills. This is an
error. Jackals often follow lions and tigers in the hope of
securing what they fail to eat up.
Like the wolf, the jackal if caught young can be tamed.
TILE EL.EPHANT
Where found, — Elephants live in the forests of Asia and
Africa. Ask who has seen an elephant. ' ]Vhere did it come
Fig. 17.
from ? ' The elephants seen in circuses are always Asiatic ;
the African is hunted for its ivory, not tamed. The African
The Elephant 99
elephant generally has larger tusks, and always very much
larger ears, than the Asiatic.
Size. — The elephant is the largest land animal. It is
generally S or 9 feet high, but sometimes reaches 10 or 1 1 feet.
Show these heights.
Legs. — ' W/iaf kind of /c\i^'s iimst the etepliaiit liave to liotd up
its gn-at body ? ' Show the thick, short, straight legs.'
Compare with the legs of a race-liorse in each respect.
Feet. — The foot is very large. ^JF/iy?' The hoof sur-
rounds it, and is formed of a vast number of horny springs not
unlike carriage springs. Elicit the effect of these, and tell that
herds of elephants can pass through a forest almost without
noise.
Skin. — Elicit that as the elephant lives in very warm
countries it needs no fur and has little or no hair. Elicit
also that as it passes through the forest, where it is liable to be
scratched, it needs a thick, hard skin.
Head. — Show that the head is large.
Tusks.— From the upper jaw (in all African elephants, and
in a considerable number of the males of Asiatic elephants)
grow two very long teeth, called tusks. These yield the best
ivory, and are very heavy, weighing from 60 or 70 lbs. to about
140 lbs.
Trunk. — Contrast the neck and head of the giraffe with
those of the elephant. Place a weight at the end of a stick,
and let the children discover experimentally that the weight is
easiest to lift when the stick is shortest. Thence show that
the heavy head and tusks of the elephant need a short, stout
neck.
Elicit that with its short neck the tall elephant could not
reach food from the ground. Hence the need for the trunk.
The trunk is really a very long and strong no.se with a finger
at the end. It can seize anything and turn in any way It
carries food and water to the mouth. Without its trunk an
elephant could not live.
Teeth and food. — The elephant has no tearing or cutting
A A child is said to have described an elephant as a square animal with a
tail at each end and a leg at each corner.
lOO Longmans' Object Lessons
teeth. Its teeth are formed for grinding only, and it therefore
lives on plants, leaves, fruits, and grains.
Habits &c. — Give brief sketches of the hunting and taming
of elephants. The school reading-books will probably furnish
stories to illustrate the sagacity, strength, and other character-
istics of the animal.
THE CAMEL
Kinds. — There are two kinds of camels, the Arabian, which
is single humped, and the Bactrian, which is double humped.
This lesson deals with the Arabian only.'
Where found. — In Arabia and North Africa. Describe as
vividly as possible the deserts over which the camel has to
pass, with their loose sand often blown into blinding, suffo-
cating clouds, and with their absence of food and water. The
remainder of the lesson will show how the camel is adapted by
its structure for crossing such deserts.
Size. — About 7 feet high — higher than a tall man.
Covering. — Long hair, some coarse and some fine. The
coarse hair is woven into cloth. ' Who wore a garment of
earner s hair 'I ' The fine hair is made into brushes for painting.
The colour is an ashy brown.
Teeth. — The camel chews the cud. Refer to the teeth of
the cow. The teeth of the camel differ somewhat from those
of the cow ; one great difference is that the camel has cutting
teeth in the front of the upper jaw.
Food. — Elicit from teeth that the food must be vegetable.
It consists of grass, leaves of trees, dates, beans, grain, &c.
Stomachs. — Refer to stomachs of the cow and the sheep.
Elicit that the camel would perish with thirst if it could not go
for a long time without water. It can do this by means of the
cells in its second stomach. When the camel drinks it fills
these cells and then closes them. When it becomes thirsty it
1 The dromedary is often spoken of as if it were a distinct species. It is
only a lighter variety of the Arabian camel, used when great speed is required.
The dromedary is related to the ordinary .Arabian camel as the hunter is to
the dray-horse.
The Camel
lOI
opens them and allows a little water to escape. In this way
the animal can go for about a week without drinking.
Hump.— The hump is not a deformity, as the camel's 'back-
bone ' or spine is as straight as a horse's. The hump is made
up chiefly of fat, and seems intended to keep the animal alive
when it can obtain no food. At the end of a long journey the
Fig 1 3. -The Camel
hump is almost gone, and the camel is not allowed to travel
again till the hump has grown to its old size.
Legs and Feet. — Ask what would happen if a horse tried
to walk over loose sand. Describe the large, broad ' shoes ' by
means of which men in cold countries walk over the snow.
Show picture of the camel's foot, which consists of large elastic
pads. These spread as the foot is placed on the ground.
I02 Longmans' Object Lessons
The camel has to kneel when being loaded. ' Why ? '
' What would haf^pen to the knees of a horse if it liad to kneel
often on the rough sand 1 ' The knees of the camel and the
part of its chest which touches the ground are protected by
hard leathery pads.
Eyelids. — ' What happens to our eyes ivhen the dust is blow-
ing ? ' ' Il7iat would happen to them if we were caught in a
sandstorm ?' The camel has shaggy, overhanging eyelids, which
protect the eye from sand and from the bright sun.
Nostrils, — Elicit that sand would suffocate if it got into the
nostrils. The nostrils are long, and can be completely closed
so that they look like a narrow slit.
Temper. — It is a mistake to suppose that the camel is mild
and gentle. It is sulky and bad tempered. Its legs often
have to be tied before it will allow itself to be loaded or even
unloaded, and it fights other camels.
7P/E BEAR
Size &C. — Show pictures of various kinds of bears. Ask
who has seen performing bears, and then question about size,
shape, colour, length of legs, &c.
Teeth. — The teeth are formed both for tearing and for
grinding, and bears, therefore, live on flesh and vegetables
(roots, corn, fruits, &c.).
Elicit that animals built like the bear could neither catch
nor creep up to other animals.
Feet. — Get from the children who ha\e seen a performing
bear that it stood easily on its hind legs. Sometimes a dog
can be trained to stand with some difficulty on its hind legs,
but animals of the cat and the dog tribes usually cannot stand
on their hind legs, because they walk on their toes. Bears can,
because they walk on the sole of the foot (see Fig. 19).
AVhen fighting, bears stand on their hind legs and strike or
hug with the front legs.
Paws, — All the paws have strong, sharp claws ; no sheaths.
The Bear
103
By means of its claws the bear can climb and dig easily. ' Why
should it want to climb ? ' ' And to dig? '
Hibernation. — Bears generally sleep through the winter.
Elicit that fruits are plentiful in autumn, and not to be found in
winter. Bears, therefore, get very fat in the autumn. About
October they dig themselves dens under rocks or beneath the
roots of trees, and there they pass the cold months without
eating and seemingly half dead. Speak of the thick, warm fur
of the bear.
Kinds. — The bear generally seen in England is the Brown
Bear, which is found in the woods and forests of several parts
Fig. 19. — Skeleton of Bear.
of Europe and Asia. This bear is fond of ants and their eggs,
and of honey.
The Black Bear is found in many parts of North America,
but as it is much prized for its fine fur it is not so common
now as formerly. Lives chiefly on vegetable food.
The Grizzly Bear is also found in North America. It is
very fierce and strong, and will readily attack man. The colour
varies greatly, but there is always a tendency to whiteness in
104
Longmans' Object Lessons
the surface of the fur : hence the name grizzly. This bear
Hves upon animals of all kinds as well as upon vegetables.
The White Bear is found in the Polar regions. The feet
are very long. Elicit that they are good for swimming. The
soles covered with a very thick coating of warm fur. Elicit
that this will keep the feet warm and prevent their slipping on
the ice. Lives chiefly on fish. ' Are there any fruits in the
cold North 1 ' Also fond of seals. The female sleeps through
the winter, but the male does not.
Tlic Rabbit
105
THE RABBIT
[For illustration have a living tame rabbit and a picture of a wild
rabbit. For the teeth have a skull.]
Home. — Rabbits live in holes, called ' burrows,' which they
make in the ground. These run for a good way and mostly
have more than one entrance, so that if a ferret, weasel, or dog
should follow the rabbits they can escape.
Large numbers of rabbits often live near each other. Their
burrows are then called a ' warren.'
Teeth.— Revise what was said about the teeth of a mouse.
The rabljit is, like the mouse, a gnawing animal. Show the two
long teeth with chisel edges in front of each jaw. At the back
of each jaw are grinding teeth. To show the action of the
io6 Longmans' Object Lessons
teeth and jaws try to get the Hving rabbit to eat some green
stuff.
Food. — EHcit that as the rabbit has no tearing teeth it cannot
hve on flesh ; but that as it has grinding teeth it lives on vege-
table food — wheat, barley, turnips, and other growing crops.
Rabbits do great damage in the farmers' fields. As they
have a large number of young ones every year, they would de-
stroy everything around them if many were not killed. Speak
about the enemies of the rabbit — foxes, weasels, sometimes
cats, and man with guns, dogs, ferrets, traps, and nets.
Rabbits do great damage to young trees, delighting to strip
them of their bark as far up as they can reach standing on their
hind legs. Sometimes they eat it, but more often they leave it
in heaps on the ground, having gnawed it off merely to keep
their teeth in order, just as a cat keeps her claws in order by
scratching the legs of tables and chairs.
Lips. — Upper lip split. Show. The hard substances which
the rabbit gnaws would cut the lips, mouth, and tongue if they
were formed like ours. The front teeth project, and the cleft
in the upper lip enables that to be drawn back. There is also
a patch of hair inside each cheek ; the skin of the tongue is
thick and hard [Show the white patch], and the roof of the
mouth has thick, horny ridges. Show.
Ears. — Elicit that as the rabbit has so many enemies it
must be very watchful, and requires good ears and eyes. The
ears are long and movable. '■Advantage of tliis ? ' When going
into a hole the ears are laid flat on the neck.
Eyes. — Large and bright, placed one on each side of the
head. Elicit the advantage of this. We can see only what is
in front of us ; the rabbit can see nearly all round.
Legs — Long and thick, showing that the rabbit can run very
fast. ' JF/iy docs it need to ? ' Hind legs longer than front,
enabling it to jump well. ^O titer animals witli hind legs longer
ttian front ? ' [The kangaroo is a notable example.]
The rabbit can sit up on its hind legs.
Feet, — The feet have spreading toes, and the front toes have
strong, blunt claws. ' What do animals like t/ie cat use their
claws for ? ' ' And the mouse 1 ' ' And the rabbit 1 '
The Rabbit \oi
Whiskers. — ' Other mdmais with whiskers ? ' 'Use of tlie
wliiskers ? ' ' ]Vhy does tlie rabbit need whisizers ? '
Covering. — Soft, warm fur — so soft and warm that the skins
are used to make muffs, caps, &c., and to line cloaks. 'Wliy
does tlie rcil'bit need warm fur t '
Ver)' )■ ling rabbits have no covering, and the mother makes
for them a \ cry warm nest of dried grass and its own fur.
Elicit iliat as the rabbit makes its burrows chiefly in sandy
soil, its sandy brown fur keeps its enemies from seeing it easily.
Tame rabbits, — Ask for the differences between these and
wild rabbits. These differences are caused by greater care in
feeding &:c.
TUJi: BEAVER
Found. — Some beavers are found in the northern parts of
Europe and Asia, but their great home is now the northern
part of North America. Impress upon the children that the
climate of those parts is very cold, and elicit that as the beaver
spends most of its time in the water it needs a specially warm
covering.
Fur. — The beaver has two coats of fur — an under layer of
short soft grey hair lying close to the body, and an upper layer
of thicker and longer chestnut hair forming a kind of thatch.
Because of its warmth beaver skin is much valued for muffs,
jackets, cloaks, c&c.
Feet. — ' Wliat sort of feet Jias tlie diub:?' ' JV/iy are tliey
webbed 2' The hind feet of the beaver are webbed for the
same reason.
Tail. — Compare the tail to the rudder of a boat and to
the screw of a steamship. It is covered not with fur but with
scales. ' Lil;e ? '
Teeth. — The beaver is a gnawing animal. ' Like t '
Food. — It lives on the bark of trees.
Size. — The beaver is the largest of the gnawing animals.
It is over 2 feet long from the nose to the root of the tail
and the tail is over a foot long.
io8
Lo7tgmans' Object Lessons
Fig. 2-.e.
The Bcavi
109
Dams.— In very cold countries the streams are often frozen
down to the ground, and in the short, hot summer they are
sometimes dried up. To keep both
these things from happening in the
streams where they live, beavers make
the water much deeper by building
great dams right across them. Illus-
trate by a good blackboard sketch, or
by having a box or little trough for
the bed of the stream, and compare
to a mill dam or to the big pool the
children themselves may have made by
damming back the water in the gutter
on a rainy day.
Having chosen a suitable spot
where there is a tree growing on the '^"^' °^'
bank, the beavers gnaw at it till it falls across the stream.
Should one tree not be long enough, they similarly gnaw
another on the opposite bank. These trees form the founda-
tion of the dam. A large number of logs and sticks are
then gnawed, floated down the stream, pressed among the
branches, and secured with mud and stones. Layer upon
layer is formed in this way till the dam is high enough. An
opening is left at the top. ' Why ? '
The labour spent in building dams must be very, very
great, as they are 1 2 feet thick at the bottom and sometimes 300
yards long. ' IIow many times as long as the school?'
[It is a popular error to suppose that beavers use their tails
as trowels.]
Lodges. — Near the dam the beavers build their 'lodges.'
These are huts formed of branches, moss, and mud, in which
several beavers live together. The walls are very thick, and,
as the winter's cold freezes the mud, they defend the beavers
against their enemies.
Around the 'lodges' deep ditches are dug, and as each
' lodge ' opens into a ditch the animals can pass into the
stream without going over land.
Winter food. — Beavers strip the bark from the logs used in
no
Longmans' Object Lessons
building their dams and store it for food in the winter. They
also cut a vast number of small logs and fasten them under
water near their 'lodges.' When they feel hungry they dive
for one of these logs, peel off the bark, and eat it, leaving the
log to float down.
THE SWALLOW
[Except in towns that the swallow does not visit, this lesson
should be given during the summer. If a bird cannot be procured,
illustrate by means of a good picture.]
The swallow is a ' bird of passage.' — B)' means of ques-
tions bring out clearly
(i) That the swallow is oftenest seen flying about swiftly,
not in a straight line, but in all directions.
(2) That while flying it feeds on insects.
(3) That insects abound in warm weather.
(4) That the swallow is in this country only during the
warmest half of the year, arriving about the beginning of April
and leaving about the end of September.
Birds which, like the swallow, spend only a part of the
year in a country, are called birds of passage.
The Szvalhnv
■HI
Shape. — Draw outlines of two boats, one narrow with
sharp bow, the other broad with flat bow. Ask which boat
would pass most quickly through the water. ' Why 1 ' Then
make children see that the swallow's body is shaped like the
first boat. Contrast with the body of a hen.
Wings. — Very long, narrow, and pointed. ' JF/iy does the
sivallmv fly about so jiiuchV "■ illiat sort of ivhigs must it
have to enable it to fly about so muck ? ' Compare wings with
a hen's. Also with an eagle's or owl's. ' A/id to carry it
to far countries V The swallow is believed to fly from Great
Britain to the north of Africa in three days. The eagle and
owl do not Avant to fly fast or far, but to keep up a long time
and to carry their heavy prey. Their wings, therefore, are
strong, but broad, not long. ' Wliy broad'!' As the swallow
has to catch insects as they fly, it must be able to dart through
the air, and it has no weight to carry ; hence shape of wings.
Legs. — Short and weak. Feet with four sharp claws, three
pointing forward (four in the swift). ' What birds have you
seen hopping about 'I ' ' Have you ever seen a sivallow hopping
about V ' JVhy cannot a sivalloiv hopV ^ Why does it not
need long or strong legs ? ' ' Have you ever seen a sivallow
hanging by a wall 2 ' ' Hotti did it hang? '
Beak. — ' The beak is short and so weak as to be almost
soft, but of vast width proportioned to the size of the body.
This may be easily seen in the common house-swallow, but
more particularly in the swift or large black swallow and goat-
sucker, whose heads may be almost said to be all composed
of mouth, so wide and gaping are their large, short beaks.
Consequently, when the supply of food is abundant they
have little more to do than fly with open mouth and close
their beaks upon the objects which cross their flight. This
the swallow does with a sharp clicking jerk, which may be
heard by an attentive listener on a calm day at a con-
siderable distance.' — Stanley's 'Birds.'
Kinds (with nests). — (i) The swallow (proper). — Can be
distinguished from the swift or martins by its steel-blue upper
plumage and the two very long feathers that edge its forked
tail. ' The swallow has perhaps never been known to build a
112
Longmans' Object Lessons
nest in the open air. In barns and outhouses, upon the beams
of wood which support the roof, or on some stone jutting out
of the wall or chimney ... we find its nest.' — Dixon's
' Rural Bird Life.'
Question about building of nest.
(2) The house-martin. — Resembles the common swallow in
habits and appearance. Can be distinguished from it by the
large white patch on its back and the absence of the acutely
forked tail. ' Unlike . . . the swallow and sand-martin, the
house-martin builds its nest in the open air, ... on the
rocks, under the eaves of buildings, or on the sides of windows
or chimneys.' — Dixon.
(3) The sand-martin. — Smallest of swallows. Back and
head soft brewn ; quill feathers of wings and tail black ; breast
white, with a band of brown across the upper part. Builds its
nest in sandy cliffs, banks of rivers, &c. Makes a narrow
tunnel from 18 inches to 4 feet long, and at the end builds a
nest of grass and feathers.
(4) Szvift. — Is unlike the true swallows in several respects
— one already mentioned (all four toes pointing forwards).
Swiftest ; cuts through the air as though shot from a bow.
Makes a shrill noise, whence it is called in some parts of the
country, 'Jack Screamer.' Nest made of feathers and grass
placed in a hole in a wall or rock or under a roof '
1 The following table, giving the names of the most conmion birds of
passage, with the earhest dates of arrival and latest dates of departure noted
by Stanley, may be interesting to teachers : —
Sand-martin
Swallow .
House-martin
Swift
Redstart .
Whitethroat
Cuckoo .
Redwing .
Fieldfare .
Woodeock
Date of appearance
Date of departure
March 27
September 21
. April II
October 20
March 20
October 20
April 27
September 15
. April 6
Septemljer 5
. April 6
September 8
. April 10
June 30
September
26
April 3
. September
29
May I
October 15
April 2
Tlie Ostrich 1 1 3
THE OSTRICH
Where found. — The ostrich hves in South Africa. Describe
the kind of country. As it is sandy the bird's long legs are
useful [' Wky f ] ; as there are no trees the bird does not want
grasping claws or wings.
A running bird. — Legs very long and very strong. Can
break a man's leg with a kick. Two toes, the outer about half
as long as the inner, which has a claw.
Food. — In a wild state the bird lives chiefly on melons, which
grow plentifully on the ground.
Neck. — Elicit that as the legs of the ostrich are very long
and its food is found on the ground, it must have a very long
neck.
Bill. — Draw on the blackboard hawk's beak, formed for
seizing prey, and a hen's, formed to pick up grain. Elicit that
neither of these would do for the ostrich, which has a bill some-
thing like a duck's.
Size. — From the long neck and long legs children will gather
that the ostrich is a large bird. Tell them it is the largest —
from 6 to 8 feet high.
Wings. — As the bird has long legs and can go faster than
a horse, it does not need to fly. Wings, therefore, very small in
proportion. Like a hen's, they help the bird to run.
Feathers. — Show. Though the wings are comparatively
small, the feathers in them and in the tail are really large and
beautiful. They are black, grey, and white, and worth a good
deal of money.
Eggs. — Very large ; contain as much as twenty-four eggs
of hen.
Hatching. — The eggs are laid in the sand and hatched
by the sun, except in the parts furthest from the equator,
where the sun's heat is not enough and the birds sit on the
eggs.
Hunting. — Hunted. ' Why ? ' Chased by men on horses.
The birds run in a zigzag line, but the horses keep straight on.
Illustrate on blackboard.
I
114
Longmans' Object Lessons
The Ostrich 115
Ostrich farms. — In South Africa ostriches are now reared
on farms. ' ]]'Iiy 1 ' The eggs are hatched in incubators.
TIf£ HERRING
[Illustrate the action of the gills, fins, and tail by having a gold-
fish or other living fish. For the special structure have a dead
herring.]
Some peculiarities of a fish.~G'//A.— ' ]Vhat do we breathe
until ? ' ' IVhat passes info our lungs 'I ' ' JF/iat does the air do
in tJie lungs 1 ' There is always a little air in the water. Show
the bubbles in water which has been standing. Also boil a
little water in a test-tube, and make the children observe the
many bubbles of air which will rise to the surface. Fish breathe
this air, but they have no lungs. They breathe by means of
their gills. Show the folds in the herring's gill, and show the
action of the gills in the hving fish. The Ijlood passes through
the gills. ' IVlmt colour are they 1 ' ' JFliy ? ' When a fish
breathes it takes water through its mouth and makes it pass
over the gills, and the air in the water purifies the blood.
£ggs. — Show a ' hard roe.' This is made up of the herring's
eggs. ' IVhaf is the difference between the eggs of a I'ird and
those of a fish '! ' [The shell] ' How many of yoic have seen
the '■'■spawn " of frogs in pools and ditches in spring t'' This is
made up of the eggs of frogs. The eggs of some fish look
like that.
' What causes a hen's eggs to hatch ? ' The eggs of fish are
also hatched by heat, but it is the heat of the sun. By refer-
ence to the times which it would take a large kettle and a small
one to Ijoil, elicit that shallow water gets Avarm sooner than
deep, h'ish that live in the depths of the ocean lay their eggs
near the shore.
Shoals. — About July or August millions of herrings appear
in some of the British seas. Name the seas. I'hey are then
in the best condition for eating, and it is then that they are
caught. ' JFhy could they not be caught in deep ivater 1 '
I 2
I r'6 Lcngmans' Object Lessons
Description. — Using the herring provided get the children
to describe it — length, shape [Compare to racing-boat or swift
ship], eyes, no lids ['/F/y?'], scales [Note how they are
silvered], lins, and tail [Show use by living iish].
Fishery. — Describe the fishing as graphically as possible.
Curing'. — ]Vhite herrings are simply gutted and salted.
Other herrings are gutted, strung on sticks, and hung in a
room which has fires (generally of oak) lit on the floor. If re-
moved after twelve or fourteen hours' smoking they are called
bloaters ; if allowed to remain about twelve days they become
red herriiK's.
C : Lessons on Plants
FLAX
[If this lesson is given in the summer there ought to be no
difficulty in procuring specimens of the flax plant, for in those
districts where it is not cultivated it grows wild among the corn.
Some of the linen manufacturers are kind enough to give illustra-
tions showing eveiy process through which the fibre passes.]
Two uses. — Show fibre and linseed. The flax plant is
grown either for its fibre, which is made into linen, or for its
seed, which is made into linseed oil and oil-cake. It flourishes
in cold countries like Russia, and in hot countries like India ;
but in the former the fibre is good and the seed nearly value-
less, whereas in the latter the seed is valuable and the fibre of
little use.
Where grown. — The soil best suited is one that is fairly
firm and moist. This is why it grows so well in Ireland,
Holland, and the flat parts of Russia.
Cultivation. — The details of this may be passed over.
Pulling. — If the flax is grown for its seeds, it is allowed to
ripen ; if for its fibre, it is pulled up by the roots when the
plant has reached its full height. Elicit that pulling gives a
greater length of fibre than cutting would.
Flax 1 1 7
Seeding. — The linen manufacturer does not want the seeds,
so they are taken away by pulhng the flax through the teeth of
an iron comb. Illustrate with the fingers.
Retting. — Let the children see that the stalk is made up of
a woody and of a fibrous part. The linen manufacturer wants
only the fibre. To separate this from the other part, the first
thing is to steep the flax in water for a week or a fortnight.
The soaking rots the wood and also loosens the fibres from it,
almost as soaking loosens a piece of paper that has been pasted
on anything. When the flax has been steeped long enough it
is taken out and dried.
Breaking and scutching. — Elicit that as the wood is now
rotten, while the fibre remains tough, the one can be broken
without injury to the other, and the next two processes (details
of which can be ignored) break and remove the woody part,
leaving the fibre entangled.
Heckling. — The fibres are passed through the teeth of a
kind of comb to be straightened and arranged. The short
fibres fall to the ground. These form toiv, which is used for
making twine and cord.
Spinning &c. — In this lesson the remaining processes in
the manufacture of linen should be simply mentioned ; but
when the children are a little older they may have a lesson on
spinning, weaving, &c., considered generally. This will lighten
lessons on the separate materials — linen, cotton, and silk.
COTTON
What it is. — Refer to thistledown, and to the seed in the
middle of each little ball. Cotton is the soft white down
covering the seeds of a plant.
Where grown. — Cotton takes about seven months to
grow, and, as the least frost injures it very much, it can be
grown only in those parts of the world where for more than
half the year there is no frost whatever. It also requires a fair
amount of moisture, but too much rain is not good for it. It
1 1 8 Longmans' Object Lessons
is therefore grown largely in the south-east of the United
States, in India, in Egypt, and in Brazil.
The plant. — The plant is from 2 to 4 feet high (about
the height of a gooseberry bush). It has dark-green leaves,
shaped somewhat like the leaves of the sycamore. The flower
is in form very much like the single hollyhock, but is yellow in
colour with a purple centre. When the flowers go off, pods
appear, about the size of an apple. These partly open, showing
the cotton and the seeds. Show. The seeds are about as big
as a pea slightly flattened.
Cultivation. — In the United States cotton is generally
planted in rows, pretty wide apart, to allow of hoeing and
weeding. Where the climate is at all moist the earth is ridged
up about the roots, so that when there is too much water it
may drain off
Gathering. — When ripe, the cotton is gathered by hand,
and placed in baskets carried by the picker. It is then dried
in the sun.
Ginning. — Before it leaves the plantation the seeds are
removed by means of a gin. In India the gin consists of two
rollers placed close together. The cotton is made to pass
between them, and the seeds are left behind. In America a
saw gin is used. This consists of a box, one side of which is
made of strong straight wires so close together that the seeds
cannot pass between them. Small round saws work between
the wires, dragging the cotton through and leaving the seeds
behind.
Bales.^The cotton is then pressed together very hard and
packed in bales, which are sent to Lancashire and other places
where the manufacture of cotton goods is carried on.
Manufacture. — As in the case of flax, the processes need
be no more than indicated.
Cork 119
CORK
Bark. — Show pieces of the branches or twigs of several
different trees. Strip the bark off each ; show it, and get or
give the name.
Cork is the rough outer bark of a kind of oak which grows
chiefly in Spain. The tree is much smaller than the English
oak, being only about 30 feet high. Make the height concrete.
The tree also differs from the English oak in being evergreen.
Ask what that means.
Stripping. — The trees shed their outer bark sometimes, but
generally it is stripped off One cut is made round the trunk
near the ground, and another just below the branches. Then
several cuts are made downwards from one ring to the other.
The end of a kind of bar is placed in the cut, and the cork
forced off the trunk. Illustrate with a pointer or poker. Care
is taken not to injure the inner bark. If that were destroyed
the tree would die. The tree is first stripped when it is about
twenty years old, and it is stripped again every eight or ten
years.
Preparation. — ' What is the shape of each piece of cork when
stripped off? ' In order to flatten it, it is placed in pits with
heavy weights on the top. Illustrate. Water is then let into
the pits, and the cork is left to soak for a time. It is then
dried before a fire and slightly charred. This closes the pores
[' JVhy must the pores be closed V\ and makes the cork keep
its flatness.
ftualities and uses. — Show that it is elastic, and that water
will not pass through it. Hence it is used for corks and
bungs.
It is very light. Show that it floats easily, and will bear a
considerable weight without sinking. Hence it is used for
life-buoys ; also for ' floats ' of fishing-nets.
Being light and dry, it is used for ' socks ' — thin soles worn
inside boots and shoes.
The shreds, mixed with indiarubber, are made into
linoleum.
I20 Longmans' Object Lessons
LEA VES
[(i) The lessons on Leaves are directed almost exclusively to
the cultivation of the observing powers.
(2) The matter provided will probably prove sufficient for five
lessons, but the amount to be taken at once must necessarily
depend on the time allotted to a lesson.
(3) If not amply illustrated with actual leaves the lessons will be
worse than useless.
(4) It follows, therefore, that the lessons should be given while
trees are in, full leaf.
(5) The particular leaves suggested for illustration have been
selected because it is believed that they are all easy to procure.
Should there be a difficulty in finding any leaf named, another,
having the same botanical peculiarity, should be substituted for it.]
PARTS OF A LEAF
[Give each child
(i) Leaf with petiole and stipules, as apple.
(2) Leaf with petiole but without stipules, as ivy.
(3) Sessile leaf, as wallfiower.
(4) Wheat (not in ear) or grass.
In the case of the first three the leaf should be on the stem,
and in the case of the fourth the sheath should be present.]
The blade. — Make children hold up apple leaf and point to
the blade \lamuta\.^
Let them do the same with the ivy, wallflower, and grass.
Teach the term blade.
The stalk. — Make children hold up apple leaf and point to
the stalk {petiole).
Do the same with the ivy.
Let them hold up the wallflower leaf. Ask children to
show stalk. This will impress on them the absence of stalk.
So with the wheat. Show that there is no stalk as in the
apple and ivy, but that there is a sheath which takes its place.
1 The technical terms are not to be taught. They are inserted for the sake
of the teacher. Some of them have no simple name corresponding, and 'f^
only a simple name made up for these lessons were inserted there might be some
doubt about its meaning.
Leaves
121
The leaf-scales {stipules). — Make children see that where the
stalk of the apple leaf joins the stem there are two very small
leaves. These are sometimes called leaf-scales.
Then make them see that the stipules arc wanting in the
ivy and wallflower.
Fig. 27.— Wallflowe
Fig. 26. — Leaf of Apple, with
petiole and stipules.
Fig. 28. — rt, split leaf-sheath
of a Grass : b, ligule ; c
node of the culm ; . When there is, as in this case, only one, it is called
the mid-rib.
Ribs. — Make children point out all the ribs in the maple
leaf and see that there is no mid-rib.
Fig. 29.— Ciliate
leaf of the Beech.
Leaves
123
F[G. 30, — TietiCLil.ltcIy veined leaf of Acer aruti/olinjiK
Veins. — Make children point out veins on beech and
maple.
Veinlets, — Let the children hold the leaves up to the light.
Between the veins they will see finer lines. These are called
veiiilcts.
Recapitulation. — As in the case of venation.
SIMPLE AND COMPOUND LEAVE.S
[Distribute specimens of various compound leaves, as ash,
acacia, horse-chestnut, poppy, clover, &c.
Also some simple leaf with bud at the angle where the stalk
joins the stem (the axil)^
Simple leaf. — Show the simple leaf Make the children
see
(i) That the green matter is continuous around the ribs.
(2) That there is a bud in the axil.
124
Longmans' Object Lessons
Compound leaf. — Show a compound leaf (ash or acacia, say),
and make the children see
(i) That the green matter is not continuous around the
ribs.
(2) That there is a central stem with little leaves branching
out on each side of it.
(3) That there is no bud at the axil of these little leaves.
The first kind of leaf is
called simple, the second com-
poiaid.
The little leaves of the
compound leaf are called
Fig. 31,— Compound leaf of Acacia, with
opposite leaflets and spinous stipules.
Fig. 32. —Compound leaf of Common
Poppy.
leaf-lets [compare with vein-lets'] ; their stalks might be called
stalk-lets {petiolule).
Some kinds of compound leaves.— Refer to feather-veined
leaves. Ask children to pick out compound leaves with the
leaflets similarly arranged (as acacia). These are caWeA feat/ier-
like (piiuiate).
Leaves
125
Ask children to pick out compound leaves with leaflets
arranged like outstretched fingers (as horse-chestnut). These
are called finger-like {digitate).
Then show other compound leaves, and call attention to the
arrangement of the leaflets.
Recapitulation. — Produce miscellanous leaves. Ask chil-
dren to divide them first into simple and compound ; then to
classify the compound.
SHAPES OF LEAVES
[Get leaves of as many different forms as possible, including
grass. Guelder rose, beech, oak, endive, holly, sycamore, geranium,
dandelion, thistle, lilac, ash, nasturtium, radish, or other leaves
having the same characteristics. Explain that you are going to
divide them into classes. The classification ' may be fourfold,
depending upon
(i) General outline.
(2) The margins.
(3) Incision.
(4) Apices.
When any leaf is shown ask the children to pick out or name
other leaves having the same characteristic]
-Acerose leaves of the Scotch Fir
Fig. 34. — Lanceolate
leaf of the Privet.
Fig. 33.
' From the teacher's point of view the classification of leaves is not of much
importance, but getting children to use their eyes and to describe what they see
is of great importance.
126
Longmans' Object Lessons
(i) General outline.— A few out of the great variety of
outlines may be shown. Dealing with leaves easily procured,
we may show outlines which are —
Sword- shaped (ensiform or linear), as grass.
Needle-shaped {acerose), as pine.
Lance-shaped {lanceolate), as privet or willow.
Shield-shaped [peltate), as nasturtium.
Egg-shaped [ovate), as a rose.
Heart-shaped [cordate), as lilac.
Hand-shaped [palmate), as maple or sycamore.
Feather-shaped [pinnate), as ash.
Lyre-shaped [lyrate), as radish.
(2) Margin. — The margin may be smooth [entire), as in grass
or iris.
It may be tooth-like [dentate), as in the Guelder rose.
Fig. 35. — Dentate leaf
of Guelder Rose.
Fig. 36. — .Sinuate leaf ot
the Oak.
Fig. 37. -Spiny leaf
of the Holly.
It may be hairy (ciliate), as in the beech (Fig. 29).
It may have rather large hollows between rounded parts
[sinuate), as in the oak.
It may be crisj'cd, as in the garden endive or curled dock.
It may be spiny, as in the holly.
(3) Incision, — This subject is rather too difficult for young
children. Show them a few examples of incised leaves, as hop,
sycamore, passion-flower, geranium, dandelion, thistle.
Leaves
127
Fig. 38. — Leaf of
Dandelion.
Fig. 39. - \^^^i o[ CcrauLU}n pratensc.
(4) Apices. — The points of the leaves are
of different shapes. Call attention to the
points of the leaves produced, and make
the children describe the shapes.
EDIBLE LEAVES
As a summary of the preceding lessons on Leaves a lesson
may be given on Edible Leaves. Get from the children a list
of the leaves eaten cooked, such as rhubarb, the many varieties of
cabbage, turnip-tops ; and the leaves eaten in salads, as lettuce,
endive, ' mustard and cress,' &c. Have specimens of each
kind of leaf spoken of, and question as to its botanical charac-
teristics. Ask for the blade, stalk, and leaf-scales, ribs, mid-
rib, veins, veinlets, the venation and framework, margins,
outhne, &c. Also ask what other leaves with the same charac-
teristics the children have seen.
If drawing is taught, the outlines and venation of leaves
should form subjects of two or three lessons.
128 Longmans' Object Lessons
TEA
Leaves. — Show the class some leaves that have been taken
from a tea-pot and stuck on white card. The size and shape
will thus be seen.
Where grown. — ' On what did tluse leaves grow ? ' ' Which
of you has seen a tea-plant V [No one.] 'JVhy not?' It
grows in China, the North of India, and Ceylon. Show on the
map.
The shrub. — Show a picture. If there is not one in the
school one can probably be obtained from some advertising
tea-dealer. Failing this, draw sketch on the blackboard with
coloured chalks.
The shrub is an evergreen. ' IVhat does that mean- ? '
' Natne some evergreens that you knozv.'
It is from three to six feet high. Show height. It would
grow higher if it were not cut down. ' Why is it ait down ? '
[To get more leaves and less wood.] To make this clear get
out why a quickset hedge is frequently cut down.
If the children have seen a myrtle say that the shrub re-
sembles it. The leaves are of a bright deep green, and the
flowers are a good deal like those of the camellia.
The gathering. — The leaves are first gathered when the
shrub is three years old There are three gatherings in the
year — in spring, summer, and autumn. Recall the fact that the
shrub is an evergreen. The spring crop is the best, and the
autumn crop the worst.
The leaves are gathered one by one by people wearing
gloves. ' Why are gloves worn 1 ' Fold a piece of paper, place
some juicy leaf between the folds, and squeeze ; then open the
paper and show that the leaf is crushed and the juice gone.
The tender tea-leaves might be crushed if gathered with the
naked hand.
The drying. — ' JVho has turned over a heap of leaves ? '
Thence get out that the lower leaves were rotting. If the
tea-leaves were sent to this country as gathered they too would
rot.
Tea 129
The leaves are dried in a flat iron pan on the top of a
kind of stove. Illustrate by drying some leaves on a hot shovel
or other metal plate, and show that if they vs^ere not stirred they
would shrivel up.
When the leaves are hot they are poured on mats placed on
a table. Then they are rubbed with the hands in one direction
to make them curl. Illustrate with the leaves already dried.
Show some tea, and let children note similarity. The roasting
and rubbing are repeated several times till all the moisture has
gone. Then they are ready for use.
ELLnds. — ' Hoiv many kinds of tea do you know ofl ' The
black tea consists of the older leaves. They are placed in a
heap after they are gathered, till the heat thus formed darkens
them. [If the lesson is given to rural children compare to the
' heat ' of a new hayrick, and call attention to the difference in
colour between grass and hay.]
Green tea consists of the younger leaves dried and rolled as
soon as gathered.
Poor kinds are dyed.
TOBACCO
[Tobacco is often grown as an ornamental plant. If the teacher
knows any garden where it is so grown he should procure a leaf or
two. A dried leaf can be obtained at a tobacconist's.]
Forms. — Show the leaves, and say what they are.
(i) The leaves are cut for smoking in pipes and cigarettes.
(2) They are folded for smoking as cigars.
(3) Certain parts of them are dried and ground for snuff.
Where grown. — Tobacco was first brought from America,
where it is still largely grown. It will grow in any country
where they do not have sharp frosts. 'What ivould frost do
to it ? '
Growth. — Compare the first stages in the cultivation of the
tobacco plant to the first stages in the cultivation of cabbages.
The seeds are set in hot-beds. When the plants are about four
K
130 Longmans' Object Lessons
inches high they are transplanted. ' Why ? ' [For hght, air,
and room to grow.] Till the warm weather comes they are
covered at night. ' JVAy ? '
The fields are carefully weeded. Decaying leaves are
plucked off. The flower is also cut off. Explain that this gives
greater strength to the leaves.
Harvesting. — When the leaves become of a yellowish-green
they are ready to be harvested.
The plants are cut close to the ground, and hung up in barns
for about a month to dry. Then they are piled in a heap to
sweat.
The leaves are now tied into bundles called hands, packed
in hogsheads, and sent to the place where they are to be
prepared for use. [The details of the manufacture can be
ignored.]
Moral. — Many people believe that tobacco is harmful to
everybody. There can be no doubt that it is very harmful to
all persons who are not full grown.
131
THIRD YEAR
A : Lessons on Elementary Chemistry and Physics
OXYGEN
[Hints to the teacher. — Oxygen may be made by heating
chlorate of potash (potassium chlorate) or black oxide of manganese
(manganese di-oxide) ; but it is best prepared for experimental
purposes by using a mixture containing about ec[ual weights of the
two substances, as the gas comes off at a much lower temperature
than when either is used alone.
Place the mixture in a flask (as shown in the following cut) or
in a glass retort. The flask must be provided with a cork through
which a bent glass tube passes. Nearly fill a pneumatic trough
with water, and above each hole in the shelf of the trough place
an inverted jar filled with water.
Fig. 40.
Place the bent end of the delivery tube under water (not
under any of the jars), and apply heat to the flask. The bubbles
at first given off consist of the air driven out by expansion. When
all the air has come off, place the tube under the first jar. When
that is full, place the tube under the second jar. While that is
filling, cover the mouth of the first (under water) with a greased
132 Longmans' Object Lessons
glass disc. Proceed thus till as many jars are provided as will be
required.
If the teacher has no proper flask or retort, the ' Florence
flasks ' in which olive oil is sold offer a satisfactory substitute.
See that they are without flaw, and choose the thinnest. If a thick
one is used, the heat may crack it by expanding unequally the
inside and the outside.
The cork must fit exactly. To make sure of its being air-
tight, rub a little grease around the edge of the flask after the cork
has been inserted.
The hole for the glass tube is best made by means of cork-
borers — small brass tubes, the lower ends of which are sharpened.
Select a borer which is a shade less in diameter than the tubing
to be used, and, if necessary, clear it with the rod provided for the
purpose. Begin at the small end of the cork, and take care that
the hole is made straight.
There is no satisfactory' substitute for the borer. Perhaps a
small pointed triangular file is the least unsatisfactory. First push
an awl straight through the cork, and then enlarge the hole with
the file, making the tubing in the cork air-tight with grease.
The best way to bend glass tubing is to hold it horizontally in
a gas-flame from an ordinary burner the long way of the flame.
Fig. 41.
Keep twisting it round till it begins to soften, and then let it bend
over to the right shape by its own weight.
To cut glass tubing make a notch in it with the triangular file,
then bend it away from the notch, pulling at the same time. The
sharp edges can be rounded off by making them red-hot.
If the teacher has no proper gas-jars, large-mouthed glass fruit
or pickle bottles will do very well instead ; but the mouths must,
if necessary, be ground flat. To do this, get a piece of plate
glass 6 or 8 inches square ; place on it some fairly coarse emery
and some water. Hold the bottle mouth downward on the plate,
and rub hard with a circular motion. When collecting gas, grease
the glass plate to make it air-tight.
Oxygen
133
A cheap form of pneumatic trough (shown in the following cut)
consists of an earthenware basin with a little stand, called a
bee-hive shelf
Failing any form of pneumatic trough, a flat-bottomed pan
having an improvised shelf with perforated holes may be used.
The risk of breaking the flask may be reduced if the mixture
is first warmed gently at the top, and the flame is brought gradually
downward as the gas begins to be given off.
As soon as the jars of gas are full, lift the end of the delivery
tube out of the trough. Otherwise, as the hot gas cools and
contracts, the water will rush up the tube and crack the flask.]
A gas. — If the gas is laid on, turn the tap, but do not light
the gas. ' What is coming out here ? ' There are many different
kinds of gas, and this is called 'coal-gas.' ' Can you see it?'
' Can you smell it 1 ' ' Can you feel it ? ' (Only when it is in
motion.) ' JVill it hum ? ' Light it for a moment.
But for the little coal-gas now in it, the room is full of
other gases. ' Can you see them ? ' ' Smell them ? ' ' Feel them ? '
' Will they burn ? ' Light a match to show that they will not.
These gases together make up the air. One of them is called
oxygen.
Some properties of oxygen. — Show the jars containing
oxygen. Make the children perceive that it has no colour,
smell, or taste. Warm the oxygen mixture a little, and let the
gas escape into the air. Apply a match to the end of the
delivery tube. The gas will not burn. Tell the children about
some people being suffocated while sleeping in a room into
134
Longmans^ Object Lessons
which coal-gas was escaping. That proved that we cannot
breathe coal-gas. We can breathe oxygen ; in fact, we should
very soon die if we had none to breathe.
Tilings burn in oxygen. — Many experiments can be per-
formed to show that things burn in oxygen better than they
do in air.
(i) Light a splint of wood. Blow out the flame, but leave
a glowing spark. On being dipped into a jar containing oxygen
this spark bursts out into a flame.
(2) Show that it is difficult to burn charcoal in air. Then
put a piece on a deflagrating spoon, as in Fig. 43 ; ignite, and
place in the oxygen. The charcoal will at once glow brightly
and throw off brilliant sparks. [A piece of wire, one end of
which is passed through a cork and the other twisted around
the charcoal, will do instead of a deflagrating spoon.]
-JT
s
,rns
y«
Fig. 43.
Fig. 44.
(3) Burn sulphur similarly in air and in oxygen.
(4) Show that a piece of iron wire will become red-hot in
air, but will not burn. Dip the red-hot end in oxygen, and the
iron itself will burn brifliantly (Fig. 44).
Other similar experiments may be performed if the apparatus
and materials are available, but the teacher must take care to
impress upon the children the truth which the experiments
illustrate.
TMngs will not burn without oxygen. — Things burn in
the air because of the oxygen in it. As they burn they use up
the oxygen, and when it is all used they go out.
Oxygen
I3S
Over it place a
^-
Stand a lighted candle in a shallow dish
bottle or jar, and pour into the dish
enough water to cover the mouth of
the jar or bottle, and thus prevent
the entrance of air. When the candle
has used up all the oxygen it will go
out.
If instead of the bottle we had a
bell-jar (as in Fig. 45), we could lift the
stopper and re-light the candle. Then
if we admitted air below by means of
a tube, the candle would continue to
burn. [A fruit or pickle-bottle from
which the bottom has been removed is a satisfactory substitute
for a bell-jar.]
i
Fig. 45.
NITROGEN
Revise the last lesson so far as may be necessary to re-
impress on the children's minds —
(i) That the air is almost entirely made up of two gases.
(2) That oxygen is one of these.
(3) That some of the oxygen is used up when anything is
burned.
Nitrogen. — [For the success of this lesson a bell-jar (or
some such substitute for one as was suggested at the end of the
preceding lesson) is essential.] Take a piece of phosphorus
about as large as a pea ; dry it with blotting-paper, and then
place it on a large piece of cork floating in a shallow dish con-
taining a little water. Cover with a bell-jar. Remove the
stopper, ignite the phosphorus with a piece of red-hot wire, and
immediaUly replace the stopper. The jar will be filled with
dense white fumes. When these have settled it will be seen that
the water has risen some way in the jar. Measure, and prove
that it has risen one-fifth. ' With what was the jar filled at
first 1 ' ' And ofi how many gases was this air made up ? '
' What is the name of one of them 1 ' ' WAat became of this as
136
Longmans' Object Lessons
the phosphorus burned ? ' ' Why did the phosphorus go out ? '
How ma tiy gases are there now left i?i the jar V '■What took
the place of the oxygen ? ' The other gas
is called nitrogen, and it forms four-fifths
of the air.
Properties. — Pour water into the
vessel till it reaches the level of that
inside the jar. Make the children per-
ceive that the gas inside the jar has no
colour [Should there be any colour it is
caused by the fumes of the burning
phosphorus], smell, or taste. Place a
small lighted taper in the nitrogen. It
at once goes out, thus showing that
things will not burn in nitrogen.
Contrast the properties of oxygen and nitrogen. Remind
the children of the great rapidity with which things burned in
oxygen. Hence elicit the
Use of nitrogen. If the air were made up of oxygen alone
it would be too strong for us to breathe. We should be used
up as fast as things are burned up in it alone. Hence the ne-
cessity for ' diluting ' the oxygen with nitrogen. Compare to
the way in which mother adds water to tea which is too strong.
CARBONIC ACID GAS^
[The apparatus required for the preparation of carbonic acid
gas is shown in fig. 47.
An ordinary fruit or pickle bottle will do, if fitted with a large
cork. In the bottle place small pieces of chalk, limestone, marble,
or any other carbonate. To this add hydrochloric or some other
acid.]
Properties. — (i) Dip a burning taper or candle into a jar
containing the gas. The light will go out. This proves that
things will not burn in it.
1 The name which chemists now give this gas is carbon di-oxide. This has
the merit of indicating the composition, CO^.
Carbonic Acid Gas
137
Fig. 47.
(2) Take a jar containing only air. To show that it con-
tains air place a lighted candle in it. Pour into it the carbonic
acid gas, and prove that you »?
have done so by again placing '
the lighted candle in. This
shows that carbonic acid is
heavier than air — which also
is proved by the method of
collecting the gas.
(3) Pour a little lime-
water' into a jar. Introduce
some gas into the water, which
turns milky. Make the chil-
dren note this carefully, as
this is the test for carbonic
acid.
We breathe out carbonic acid gas. — Let some of the
children breathe through a tube into some lime-water, which
will become milky. ' What does this show 1 '
There is a little carbonic acid gas in the air. — The experi-
mental proof of this cannot be performed in the course of a
lesson. If some lime-water be exposed to the air for a day
a thin film will form on the top, and in a few days it will be
milky. This proves that the air contains the gas, but contains
very little. It really forms four parts out of 10,000.
Carbonic acid gas is formed when things ^ burn. — Place a
candle in a bottle containing carbonic acid gas. When the
candle has gone out, pour a little lime-water in and shake it up.
It turns milky.
Food for plants. — Plants help to purify the air, because
they take from it and use for food the carbon or carbonic acid
[' What remains ? '], and they give out oxygen. (See p. 232.)
' If lime-water cannot be readily procured, prepare some by putting a
piece of common lime about the size of a hen's egg in a quart of water, allow-
ing it to remain there three or four hours, and then filtering the liquid through
filter-paper placed in a funnel,
- Strictly speaking, when carljonates burn.
138
Longmans' Object Lessons
HYDROGEN
[How to prepare.— Hydrogen is generally prepared in aWoulffe's
bottle, as shown in Fig. 48.
If there is not one available use a wide-mouthed bottle, and bore
two holes in the cork, one for the thistle funnel and the other
for the delivery tube. The whole
apparatus must be made air-tight.
Place in the bottle about an
ounce of zinc cuttings or zinc nails.
Cover them with water. Then
through the thistle funnel, pour in
a little sulphuric acid, and hydro-
gen is given off through the delivery
tube. Keep the apparatus at a
distance from any flame.]
Properties. — (i) We collect
the gas by placing a test-tube
over the delivery tube. Make
the children see that this shows
the gas is lighter than air. It is
Fig. 48. the lightest gas known.
(2) Connect an ordinary clay
pipe with the delivery tube by means of indiarubber tubing.
Dip the bowl into a solution of soap so that the gas may
blow a bubble. This, when detached, rises rapidly into the
air. Show how much slower a bubble blown with the breath
rises. A small balloon made of gold-beaters' skin will rise if
filled with hydrogen.
(3) If the end of the delivery tube has been made small by
holding in a flame, apply a light to it. The gas burns with
great heat but little light.
(4) Fill a test-tube with hydrogen. Apply a light. There
is a loud explosion and the gas burns. A mixture of hydrogen
and o.xygen, or of hydrogen and air, is explosive.
(5) After the last experiment look at the tube. Its sides
Hydrogen 1 39
are wet. The burned hydrogen and the oxygen necessary for
burning it formed water. Water consists of one part of oxygen
and two of hydrogen.'
A BURNING CANDLE
What does not burn. — Light the candle. ' Of how ma^iy
parts is this candle made upV ' Which of them is burning ? '
Apply a light to fat without wick and to wick without fat,
and thus show —
(i) That the fat will not burn at all, and
(2) That the wick burns badly for a very short time and
then goes out.
What does burn. — Place a little fat in an evaporating-dish
or watch-glass ; warm till vapour arises, then light the vapour.
' What is burning ? '
Light the candle. Blow it out. Apply a match to the
smoky vapour arising, being careful that the match shall not
touch the wick. The vapour will light and communicate flame
to wick.
When a candle is first lighted the heat of the burning wick
forms a little cup containing melted fat. The wick sucks up
this fat, which the heat changes into vapour that burns. ' Why
does a candle, when first lighted, nearly go out sometimes, and
then flame up suddenly 1 '
The flame. — Place lighted candle under tumbler or other
glass vessel. Candle goes out. ' Why 1 '
Burning goes on only in contact with oxygen. The flame
is therefore hollow. The shape of the flame will best be seen
if a lamp-glass is placed over the candle. The glass must be
so placed as to admit air below, or the candle will go out.
To show that the flame is hollow take a piece of white
paper ; hold it, with the surface horizontal, in the middle of
the flame ; remove before ignition takes place ; rub off the soot,
and a scorched circle will be seen.
^ The fact that the two gases must be chemically, not mechanically , com-
bined, may be ignored at present.
140 Longmans^ Object Lessons
The hollow of the flame is filled with gas which will burn.
Hold one end of a glass tube very steadily in the lower part
of the flame ; apply a light to the other end, and the gas from
the hollow of the flame will then burn.
What becomes of the candle. — The fat of the candle is
made up chiefly of hydrogen and carbon. The hydrogen
uniting with the oxygen of the air forms water.
Hold a glass vessel over the flame, and water will be de-
posited on the sides. The vessel must not be held too long or
the heat of the candle will dry up the water.
The carbon of the candle uniting with the oxygen of the
air forms carbonic acid gas. Show them that the gas given
off by the candle does the same, thus : —
Show this by letting the candle burn out under an in-
verted fruit-jar or other glass vessel, and then pouring a little
lime-water into the vessel and shake.
The bright part of the flame consists of burning carbon.
Some of this carbon is given off as soot. Show. The ' smoke '
consists of Darticles of carbon.
MATCHES
Tinder. — Before matches were invented there were other
ways of getting a light. One was the tinder-box.
Prepare some tinder, and procure a piece of flint and a piece
of steel. [The back of a pocket-knife will do well for the steel.]
Strike sparks, and let them fall on the tinder. Show that it will
glow, but not flame.
Sulphur matches. — The difticulty of obtaining a flame was
got over by touching the glowing tinder with something that
would easily light, such as a sulphur match.
Prepare sulphur matches by melting a little sulphur and
dipping into it the ends of dry splints of wood. [The wood
of ordinary matches will do.] Touch the glowing tinder with
one of the sulphur matches.
Chlorate of potash and sugar. — Matches were also made
Matches 1 4 1'
by dipping the ends of splints into a mixture of chlorate of
potash, sugar, and gum. ' Why gum ? ' [To make the mixture
stick to the wood.]
Prepare matches as described, or drop a little sulphuric
acid on a mixture of powdered chlorate of potash and sugar.
The matches were lit by dipping them into sulphuric
acid.
Phosphorus. — These methods of getting a light fell out of
use when phospliorus matches were invented.
Friction causes heat, and the heat, if great enough, causes
flame.
(i) Let a child rub a brass button on the desk. ' IP^/iaf
makes the button hot ? '
(2) ' When a train is going very quickly the wiieels or axles
sometimes get on fire. Wliy ? '
(3) ' IfoiV do savages get a liglit 1 '
Phosphorus lights with very little heat. — Show bottle
containing phosphorus. ' What is the liquid in the bottle 1 '
[Water.] ' PVhy has the phosphorus to be kept under water ? '
' Why do we rub a match t ' [llie friction gives heat enough
to make the phosphorus light.]
Phosphorus matches. — The heads of matches are now
generally made of a mixture of phosphorus, chlorate of potash,
sugar, gum [' JFhy gum 1 '] and colouring matter.
Safety matches. — Rub an ordinary match on anything
rough. ' What causes it to light 1 ' [The phosphorus.]
Rub a safety match. ' Why will it not light 1 ' [There is
no phosphorus in it.] Rub it on its own box. It lights be-
cause there is a little of a kind of phosphorus on the box.
Rubbing causes enough heat to make the phosphorus light the
match, though not enough to light the phosphorus itself. Let
a child feel that the box is warm immediately after being used.
Fusees. — 'What are these used for V 'Where are they
used ? ' ' IVhy would not ordinary matches do 1 ' Show that
the end of a fusee is the same as the end of another match ;
then comes the head. Strike one, and make the children note
that the first part flames and the rest glows. The glowing part
consists chiefly of nitre (saltpetre),
142 Longmans^ Object Lessons
Prepare ' touch-paper ' by steeping brown paper in a solu-
tion of nitre and then drying well. Show the paper will glow,
but not flame.
COAL-GAS
How obtained. — Fill the bowl of a clay pipe with coal-dust,
cover the top carefully with well-kneaded clay, then place
in a clear fire. At first, what looks like dense smoke will come
through the stem. This is chiefly steam. Then will come off
gas which can be lighted.
Another way is to heat coal-dust in a small flask made of
hard glass, and to collect the gas over water.
When the manufacture is conducted on a large scale, the
coal is heated in retorts of iron or fire-clay, and the gas is puri-
fied before passing into the gas-holder (or gasometer) where it
is stored.
Properties, — These may be demonstrated from the gas in
the pipes.
(i) Coal-gas will burn.
(2) It has a disagreeable smell.
(3) It cannot be breathed. Refer to cases where persons
have been suffocated by an escape of gas into the room in which
they were sleeping.
(4) Mixed with air it explodes. Show that the pure gas will
not explode — it only burns. \Vhen there is an 'escape' the
gas mixes with the air, and if a light is then brought there is an
explosion.
Explosions often occur in mines from this cause.
Safety-lamp. — To prevent these a safety-lamp is used.
Turn on the gas without lighting it. Over the escaping gas hold
a piece of fine wire gauze. Apply a light above the gauze. The
flame will not pass through it to the burner.
In a safety-lamp the flame is surrounded by fine wire gauze.
By reference to experiment show the action of the lamp.
Caution. — Never seek for an escape with a light. When
there is a smell of gas in a room, open doors and windows wide.
Coal- Gas
143
Coke. — Break the bowl of the pipe used at the beginning of
the lesson. Show the coke which has been formed. Also show
Fig. 49.
Fig. 50.
Fig. 51.
coal, and compare the qualities. ' Why does coke burn with
Utile flame ? '
VENTILATION
Carbonic acid gas is a poison. — Refer to the Black Hole of
Calcutta, and explain that the people confined in it died through
having to breathe in again and again the carbonic acid gas
which they had breathed out.
Also refer to cases in which people have been suffocated
through sleeping in unventilated rooms in which charcoal was
burning. The charcoal (carbon) combining with the oxygen of
the air made carbonic acid gas.
144 Longmans' Object Lessons
The amount of carbonic acid gas in the air is 4 parts in
10,000 ; air containing 6 parts in 10,000 is ' stuffy ' or close.
Products of combustion.— We saw (p. 137) that carbonic
acid gas is also made when things burn. But burning things
also give off tiny particles of carbon or soot. When a fire is
first lit, or when it is smoking, we can see large quantities given
off, but the particles are also given off when we cannot see
them.
Hold over a lighted lamp or candle, too far off to char it, a
piece of clean paper, and show the discolouration which imme-
diately takes place. ' What caused the blackness ? ' ' Why are
ceilings often black ? '
Eecapitulate and emphasise the cardinal facts —
(i) That living creatures poison the air of a room.
(2) That a lamp, a candle, or gas poisons the air ; and
hence show the need for getting the impure air out of rooms
and pure air in.
Hot air rises. — Light a lamp which has a chimney. Let the
children feel the hot air coming out at the top. Over the top
hold a piece of smouldering brown paper. ' Which way does tlm
smoke go ? ' ' IFhy does it rise ? ' ' JV/iy does the gas blacken the
ceiling and not the walls ? '
Get a wide-necked bottle, such as a jam or pickle bottle.
Into the neck fit a cork with holes bored in it for two glass tubes.
In the bottle place a short piece of lighted candle. Push the
lower end of one glass tube down nearly to the bottom of the
bottle, and let the lower end of the other tube be near the top.
The hot air rises to the top of the bottle, and goes out through
the upper tube. To prove this, hold a piece of smouldering
paper above the tube, and the smoke will rise. Hold the
paper over the other tube, and the smoke goes down and
through it. ' JVhat does that prove ? '
Insist on the two principles here illustrated, as they involve
the theory of ventilation and of winds also.
Ventilation, — The air in a room could be easily changed by
having one opening near the top for the hot, impure air to go
out, and one near the bottom for the cold, pure air to come in.
Open the door an inch or two if it leads to a room or passage
Ventilation
I4S
colder than the class-room. Hold a lighted candle near the top
and the flame will be blown outward ; hold the candle near the
ground and the flame will be blown in. This
shows the direction of the air currents above and
below.
Let the children feel the cold air coming in
below. They will then appreciate the objection
to ventilating a room by openings near the floor
— the draught caused.
If an opening is made above people's heads
straight through the wall into the open air, the cold
air will pour in and fall down in a stream a short
distance from the opening (Fig. 52).
Hence elicit the necessity of giving the incoming air an up-
ward direction, so that it shall come down like a fountain,
after being warmed by the air near the top of the room.
This is done in several ways — e.g. —
(i) By raising the lower sash of a window and placing a
board right across the lower opening. The air thus enters
Fic. 52.
Fig. 53.
Fig. 54. — Tobin pipe.
between the two sashes, and is directed upward by the top of
the lower one (Fig. S3).
146 Longmans' Object Lessons
(2) By fixing a Tobin pipe. Fig. 54 shows the action of
this.
There are many other ways, but these two show the prin-
ciples apphed in ventilation.
WINDS
Hot air rises. — Repeat the experiment performed last
lesson (p. 144) of burning a candle in a bottle fitted with two
tubes, and emphasise the truths it illustrates —
(i) Hot air rises.
(2) Cool air flows in to take its place.
Further illustrate the same truths by reference to a fire in
a grate. When the fire is lit it begins to warm the air around
it. This air goes up the chimney, carrying the particles of
smoke with it. Cold air from the room then flows in under-
neath the grate. ' Why is the grate raised above the ground ? '
The sun is to the air of the whole earth what a fire is to the
air in a room.' By heating the air and causing it to rise in one
part of the earth, the sun makes currents flow in from colder
parts. These currents are called Hinds.
Land and sea-breezes. — The effect of the sun in causing
winds may often be noticed at the sea-side in summer. In the
morning a breeze will be felt blowing towards the sea, and in
the evening a breeze from the sea.
The land gets hot much sooner than the water. The stones
on the beach will on a sunny day be almost too hot to touch,
while the sea willbe pleasant to bathe in. On the other hand,
the water keeps its heat much longer than the land.
Towards evening the land will have heated the air above it
so much as to make currents set in from the sea.
At night, however, the land rapidly loses its heat, so that in
the morning the air over the water is the warmer, and currents
blow towards the sea.
1 The fact that the air is warmed chiefly by radiation, not by the direct heat
of the sun, may, at this stage, be ignored.
Winds
147
Trade winds. — Show a globe. Ask the children to point to
the warmest part of the earth and the coldest parts. Make
them see that the air at the equator must rise, and the air from
the poles must flow in to take its place. Hence we should
expect winds towards the equator. There are such winds
blowing steadily throughout the year. As sailors can always
count on them they are very useful for trade, and are therefore
called the Trade IVinds. Those on the south of the equator
are the South-east Trade Winds, and those on the north the
North-east.
' 'What fart of a tvheel goes round fastest V Revolve the
globe, and ask what part moves fastest. Air at the poles,
therefore, does not go round so fast as that at the equator,
and air from the poles comes to a part of the earth moving
quicker, and so gets left behind. Hence, as the earth turns
round from west to east, the Trade Winds are north-east
and south-east, not due north and south. This point may
perhaps be made clearer by drawing a chalk line vertically on
the surface of a revolving globe. Though the motion of the
chalk was vertical in space, the line is oblique on the globe.
Constant winds can be expected only when there is constant
heat in the same part of the earth. There can be no constant
winds in the British Isles, for example, because the temperature
of the neighbouring seas and countries varies so much that
currents will be blowing sometimes in one direction and some-
times in another.
RAIN AND SNOW
Evaporation. — Warm some water in a test-tube. ' What
is this above the mouth of tJie tubeV [Vapour or steam.]
' Where does it come from ? ' Thus, though we cannot see it,
there is some in the tube. Hold a lighted taper in the visible
vapour, and it then becomes invisible. Hence elicit that we
can see vapour only when it is beginning to cool.
If steam be watched coming out of the spout of a kettle a
I Omit this paragraph if the lesson is given to a dull or backward class.
148
Longmans' Object Lessons
small space near the spout will be noticed with no visible
steam. Ask the children to explain this.
Condensation. — Over the vapour issuing from the test-tube
hold a cold slate. Show the condensation into large drops of
water. Then emphasise the three facts —
(i) Heat changes water into vapour.
(2) Cold changes the vapour back into water.
(3) Vapour becomes visible as it begins to cool.
The sun causes vapour to rise from the oceans, seas, lakes,
rivers, and other pieces of water on the face of the earth.
After a shower we say that the water on the road ' dries up.'
' What becomes of it ? '
Mist, fog, clouds. — When the vapour in the air touches
the cold sides of hills or mountains, or when it comes against
a cold current of air, it begins to condense. If it condenses
near the ground we call it mist or fog, and when high in the
air clouds.
Rain. — If condensation goes on after the cloud is formed,
the small particles of water gather more moisture around them
Rain and Snow 1 49
till at last they are too heavy to remain in the air, and fall to
the ground as rain-drops.
Snow. — When the air passing through a cloud is cold
enough to change the water into ice, it falls (if it falls at all) as
snow.
B : Lessons on Reptiles and Invertebrata
THE FROG
[This lesson should be given at a season when it can be illus-
trated with a living frog. If given in the spring it should also be
illustrated with spawn and tadpoles.]
Cold-blooded. — Let children feel the frog, so that they can
perceive that it is very cold. ' You have heard people say that
their feet were as cold as ■ ? ' [Frogs.] Question as to the
differences perceived in feeling (say) cat, dog, hen, rabbit on
the one hand, and fish and frog on the other. The cat, dog,
hen, and rabbit are warm-blooded, and need coverings to keep
in the heat of the body ; the fish and frog are cold-blooded,
and need no such coverings.
Fish and reptiles. — The frog is a reptile. ' -Fish a>id reptiles
are alike in being V [Cold-blooded.] They differ in
their way of breathing. Fish breathe by means of gills, and
cannot be drowned. Reptiles breathe by means of lungs, and
can be drowned.
Fish and reptiles both lay eggs \spdwn'\ which are hatched
by the heat of the sun.
The frog at first lives the life of a fish, and afterwards that
of a reptile.
Development. — The eggs are laid in the water. At first
they are very small, but they soon swell to the size of a pea, and
a mass of white jelly forms around them. [If possible show-
spawn.]
When the egg has been in the water for some time it breaks,
and a little creature with a large head, long flat tail, and no
ISO
Longmans' Object Lessons
body comes out. (Fig. 57, in.) This is called a tadpole} It
swims just like a fish, by moving its tail from side to side.
W\ It also breathes
like a fish, by means of
gills, which are small
tufts of soft pink
threads on each side
of the head. (Fig. 57,
III, ex. br.)
When the tadpole
is full-grown the gills
become small, and at
last disappear. By
this time lungs have
grown in the chest, so
that the creature can
breathe in the air and
not in the water.
Then the body
grows large and the
tail shrinks.
Finally, four legs
grow out of the body,
the tadpole has be-
come a frog, and it
leaves the water.
Structure of frog. — Zc.t;^.?. —The front legs are short ; the
hind legs strong and very long. Ask for other animals with
long hind legs, such as kangaroo, hare, rabbit, greyhound.
Show that these, like the frog, can jump well. In France the
hind legs are eaten.
Feet. — Webbed. ' ]Vhy ? ' Ask for other creatures with
webbed feet, and show that, like the frog, they can swim well.
Still, they pass nearly all their time on land because
(i) They find their food there.
It a..
KiG. 56. — Stages in development of Tadpole
' A tadpole
head.
literally a toad-poll — a toad which is nearly all poll or
TJte Froz
151
(2) They can be drowned, and numbers are sometimes
found drowned in wells and ponds with steep sides. ' Why 1 '
Totigue. — Frogs live
on worms, grubs, and
flies. Hence they are
very useful in a garden.
The mouth is very wide,
and the tongue, which
is long and thin, is fixed
near the front of the
jaw, with its tip directed
backwards. The tip is
always covered with a
sticky substance. The
frog darts out its tongue,
the fly or other insect
sticks to it, and is drawn
in very quickly.
Eyes. — Large ; formed for seeing in the dark.
useful to the frog 1 '
Shin. — The skin of the frog is very porous and requires to
be kept moist, as it shrinks rapidly if dry. Breathing takes
place partly through the skin.
The winter. — Elicit that as there are no worms, grubs, or
flies to be found in winter, the frog must either go to a warmer
country, like the swallow, or sleep, like the bear. It sleeps. It
finds out a hole in a small cave, or under a big stone, or under
a bank, and there passes the cold months. Such a hole is often
full of frogs.
Fig. 57. — Skeleton of Frog.
' JVhy is this
THE CROCODILE
[The lizard resembles in many respects a miniature crocodile ;
one would be useful for illustration. Have also a good picture.
The diiTerences between the crocodile and the alligator can be
ignored.]
Where found, — The crocodile is found in the Nile, the
Ganges, and other large rivers of Africa and India. A kind of
IS2
Longmans' Object Lessons
crocodile called the alligator is found in the large rivers in the
hottest parts of America.
Size. — The crocodile is the largest reptile now found in the
world. From i6 to i8 feet long is a common size, but some
have been known 30 feet long.
Make these measurements con-
crete. A large crocodile weighs
as much as an elephant.
Colour. — A crocodile lying on
the water escapes notice because
its shape and colour make it
look like a floating tree-trunk or
big log. Compare this ' protec-
tive colouring ' to that of the lion
(sand) and of the tiger (jungle
grass).
Skin. — The skin of the upper
part of the body is covered with
thick horny scales. These are so
hard that no sword can cut or
spear pierce them, and bullets
Fig. \
are sometimes flattened against them. The skin under the
body is softer. Savages use the skin for shields and armour.
Tails. — The tail is very long and powerful, and by means of
it the animal can move very quickly in the water.
Tlie Crocodile 153
Legs. — The legs are short. In the water they are used to
balance the body. When angry the crocodile moves quickly
on land, but its great length causes it to turn slowly, and the
creature that it is chasing can escape by going zig-zag. Illus-
trate on the blackboard.
If the stream in which a crocodile is living dries up [Ask about
the climate of the countries where it is found], the creature
sometimes walks over land in search of water, but its feet are
soon cut and wounded so that it can hardly crawl. Sometimes
it merely buries itself in the mud of the river-bed and sleeps till
the next rainy season. If the weather is very hot and dry the
mud becomes as hard as brick, so that the crocodile cannot
move. The natives then come and kill it at their ease.
Teeth and food. — Make the children observe the great
length of the jaws, and the sharp, pointed teeth with which each
is armed. Hence elicit that the crocodile is a flesh-eater. It
feeds on fish, on the animals which come to the river to drink,
and on any living thing that it can catch — sometimes on
men.
Throat, nostrils, and mode of catching prey. — The croco-
dile, lurking under the bank, sweeps into the water with a blow
from its strong tail any creature that may come to the river-side.
The crocodile then seizes the creature with its jaws and holds it
under water till drowned.
The crocodile itself would be drowned if water got into its
lungs, but this is prevented
(i) By the position of the nostrils. They are placed at the
end of the snout, which is very long, so that they are above
water while the prey is under.
(2) There is a kind of leathery flap in the throat, and this
acts as a trap-door, keeping out the water which must enter the
mouth.
Eggs. — The crocodile lays eggs which, notwithstanding its
size, are not bigger than a goose's. It buries them in the sand
\^ To be hatched by ?'], but stays near to watch them.
The natives, knowing this, hide near and wait till it is asleep,
when they kill it.
Fortunately, several creatures are fond of the crocodile's eggs.
154
Longmans' Object Lessons
One, sometimes called ' Pharaoh's rat ' [the ichneumon], eats a
very large number of them.
The young crocodiles are only a few inches long. Compare
to lizard. As soon as they are hatched they run to the water,
where they will snap and bite as fiercely as if they were full-
grown.
SNAKES
How snakes move. — ' Hoiv many legs have snakes 1
' How do tfi£y move, then ? ' Let the children feel their own
spines. The spine or ' backbone ' consists of a number of
separate bones joined together. These bones run through the
whole length of the snake, and are joined together in the same
way as the arm is joined to the shoulder. [A ball-and-socket
joint]. Show that this joint allows great freedom of motion.
Let the children feel their ribs, and make them note that all
Snakes 155
the ribs are joined behind to the spine, and that some are
joined in front to the breastbone.
Snakes have no breastbone. Most of the bones of the
spine have each a pair of ribs all free in front. These ribs can
be moved backwards and forwards at will.
The skin of the snake is covered with scales. Some of
those on the upper part of the body are fixed all round, but
most of them are fixed only by the front edge, so that the
points directed backwards are free. On the lower surface, too,
the scales are larger and often arranged in bands.
By means of the free ribs these scales are pushed forward
and drawn back. Their free edges hitching on any roughness
in the ground or a tree-trunk, draw the body forward with a
gliding movement. Thus snakes could not move on a perfectly
smooth surface. ' Why 2 '
How snakes swallow. — Each jaw has a large number of
small, very sharp teeth, all pointing backward. These teeth
are used not for biting but for holding. The jaws are pushed
forward and then drawn back, and the prey is thus brought
further and further in.
Snakes can swallow creatures much thicker than them-
selves, because
(i) The bones of the jaw are not joined together. They
are simply held in their place by the skin, which is as elastic as
indiarubber.
(2) The ribs do not meet in front, and the skin of the body
is also elastic.
Thus the middle part of a snake's body may often be seen
bulging out, showing the shape of some animal that has been
swallowed.
Poisonous snakes. — Snakes that are not poisonous live on
creatures having no means of defence. Thus the British grass
snake lives on frogs, which, when once caught, can be easily
swallowed ; but the British viper lives on mice, which would
bite, and on birds, which would flap their wings. This snake
therefore poisons its prey before swallowing.
Poisonous snakes have no sting, but in the front of the
upper jaw they have two long, sharp, curved teeth called the
156
Longmans Object Lessons
poison fangs. When the mouth is closed these he against
the upper jaw, but when the mouth is open they project, with the
point backward. They are hohow, and at their rooc is a kind
Fig. 6o. — Poison fangs^ showing internal hollows. A, superficial view ;
B, longitudinal section ; c, tooth of hj'drophis, with open poison groove.
of large bag filled with poison. In the act of striking, the
muscles which close the jaws squeeze this bag and drive the
poison through the fang into the wound.
Fig. 6i.— Poison appar.^tns o^ Rattlesnake, a, poison bag and duct; ^, z",
.^■"j t, «, muscles of jaw.
Tongue. — A snake's tongue is small and forked. It is
used for feeling, not for stinging.
Snakes 157
British snakes. — Of all British snakes the viper is the
only one whicli is poisonous. It is generally of a dark olive
brown, though specimens may be seen yellow, red, or nearly
black. Whatever its colour, the viper may always be known by
the ' markings ' on its skin. On the top of the head there is a
black V [Remember ' V ' stands for vij>er\, and down the back
there is a row of square black spots arranged zig-zag, almost
like the squares on a chess-board.
THE BUTTERFLY
[The school museum probably contains specimens of the
chrysalis and of various butterflies. If the lesson is given in the
summer there will be no difficulty in illustrating it with butterflies
and caterpillars. A large picture is also necessary.]
Food. — Butterflies live on the juices of flowers. Hence
elicit that
(i) We see butterflies only in warm weather, when flowers
are plentiful.
(2) They need no teeth.
(3) They must have suckers.
(4) They must be able to fly.
Sucker. — The butterfly has no mouth or teeth. ' MJiy ? '
Instead of them it has a long trunk or sucker, which, when not
in use, is coiled like a watch-spring under the head. This is
divided into two parts by a slit down the middle, each part
being grooved. They have tiny hairs all the way down, and the
two parts are made into one tube by the interlacing of these
hairs. Compare to the union which can be effected between
two blacking-brushes by striking them smartly together.
These hairs keep back any particles which might be mixed
with the juice. After a meal the two parts of the sucker are
separated, and the two front legs are employed in cleaning
them.
Feelers. — In front of the head is a pair of feelers. [The
technical name, J>a//i, need not be given. The same re-
IS8 Longmans' Object Lessons
mark applies to the other technical terms that occur.] They
can be pushed out or drawn in at pleasure. Compare to
snails.
Horns (antennse). — -These stand out from the front of the
head, and each ends in a small knob. We can tell a butterfly
from a moth by the fact that the antennae of the moth have no
knobs. The use of the horns is not certainly known, but
when they are cut off the insect cannot fly.
Eyes. — On each side of the head a large eye stands out
like a bead. Show a piece of glass cut into facets. The eye
is made up of thousands of little facets, each of which can see.
' Who has tried to catch a butterfly by creeping up behind it ? '
' What did it do t ' Hence elicit that it can see in all directions.
On the top of the head, half buried in down and scales, is
another pair of eyes, much smaller than the first.
Legs. — Like all other insects the butterfly has six legs.
These are fastened to the chest. The front pair is small ; use
already given. The other pairs are seldom used for walking,
but for resting the body while the juice is sucked from flowers.
Wings. — Four. Show the beautiful colours. ' JVhat have
you noticed on your fingers after you have been holding a butter-
fly 2 ' This dust consists of little scales. They lie one over the
other like the tiles on a roof, and they are of many different
colours. When they are rubbed away there are
little black spots showing where they have been.
Eggs. — The butterfly lays eggs and then dies.
The eggs are laid upon a leaf of the plant upon
which the caterpillar that comes out of them feeds.
They are fastened to the leaf by a kind of fine glue.
Caterpillar (larva).— When the sun is warm
enough it hatches the egg, out of which comes a
little caterpillar or grub. This httle creature at
once begins to eat, first its own shell, and then the
leaves around. In twenty-four hours it eats more
than twice its own weight. Eating so much it
grows very fast, and its skin gets too small. The
skin cracks, the caterpillar comes out with another, and once
more begins to eat. This happens four or five times.
The Butterfly
1 59
Pupa or chrysalis. — Then the caterpillar finds that it
cannot eat any more. It fastens itself up to a leaf, or a twig,
or a wall, by means of threads which it spins. Compare to a
spider's web. The skin shrivels, and a very strange-looking
creature comes out. Show chrysalis or picture of one. It
now seems quite dead, and remains in this state till the warm
weather. Then the shell bursts, and out comes the perfect
butterfly.
THE BEE
[Illustrate with large picture, a few dead bees, honeycomb,
wax, and honey.]
Wild and hive bees.- — In different parts of the world there
are wild bees, which live in hollow trees or holes in the rock,
but the honey and wax are so useful that in civilised countries
bees are kept in hives.
Fig. 63.
Cells. — The first thing bees do after being placed in a hive
is to make ' honeycomb,' One bee hangs from the roof and
i6o
Longmans' Object Lessons
others hang to her. From six Httle pockets in their bodies
they squeeze out wax, which they knead with their teeth and
form into six-sided cells. Show honeycomb. Also draw, and
demonstrate that with hexagonal cells no space is wasted.
%:SSD
Fig. 64. — Drone.
Fig. 65, — Worker.
Fig. 66.— Que
Kinds. — In each hive there are three kinds of bees. First
there is the ijiteen — one to each hive. She has a longer body
and shorter wings than the others. She does not leave the
hive. She lives four years, and goes on laying eggs the whole
time, putting one in each cell.
The drone is the male bee. It has no sting and does not
work. Hence a lazy person is called a drone. There is only
one drone to about a thousand workers. In the autumn all
the drones are killed.
Most of the bees in a hive are workers. They build the
cells, gather honey, and tend the young.
Structure. — Compare with the structure of the butterfly.
The bee may be divided into the same three parts — head,
chest, and abdomen. To the chest are similarly joined six
legs and four wings.
Tongue. — Long, edged with hairs like a brush. With it the
worker licks the juice out of flowers. This juice is stored
up in a little bag till the worker returns to the hive, when
it is squeezed out into a cell, the mouth of which is then
stopped with wax.
Legs. — On each hind leg is a little basket made of stiff
hairs. In this is stored the yellow or white dust found on
flowers (the pollen). This is mixed with honey to feed the
young bees.
Sting. —The sting is in the hind part of the body, in which '
The Bee i6l
also is a poison-bag. It is the poison that causes the part
stung to swell and be painful. There are only three British
insects with real stings — the bee, the wasp, and the hornet.
The young. — As soon as a number of cells are made the
queen begins to lay eggs in them. In a few days these change
into little white grubs. They have no legs and cannot feed
themselves, so a number of workers stay in the hive to act as
nurses. After about a week the grubs begin to spin a silken
covering for themselves, and when they are about three weeks
old they come out perfect bees.
Swarming. — The hive then becomes too full, and the
queen goes off with a great number of the bees to find a new
home. She settles on the branch of a tree, all the rest hanging
around her, till the owner comes with a new hive and shakes
them into it. Before the swarming a young queen has been
hatched, and she becomes the head of the old hive.
THE HOUSE-FLY
Recapitulate the structure of the butterfly and the bee,
and show that the structure of the fly is in many respects
similar — head, chest, abdomen ; six legs ; four wings (with
modification) ; changes.
Mouth. — The mouth contains the trunk, which is tongue,
lips, and teeth all in one.
Eyes. — Elicit, as in the case of the butterfly, that a fly can
see in all directions. The structure of the eyes is the same.
Feelers. — Two. Supposed to be for hearing and smelling
as well as for feeling.
Legs. — Six, each with three joints. The feet have claws,
hairs, and soft pads. Illustrate the action of a boy's sucker.
It is believed that the pads on the fly's feet act in the same
way, and that this is why flies can walk up the window and on
the ceiling.
Wings. — ' How t?iany wings has the butterfly 1 ' ' And the
bee ? ' All true insects have four wings. Show a fly, and let
1 62 Longmans' Object Lessons
the children try to find the four. They will probably be able to
find only two ; but if they look very carefully behind those they
will see two very small ones. These are called ' balancers ' or
'poisers,' and if even one of them is injured the insect cannot
fly, but can only flutter about on the ground.
Development. — The fly lays eggs. The warmth of the air
hatches these, and out of them come little grubs. Unlike the
grub of the butterfly, these have no legs ; but they have a
number of sharp bristles set round each of the rings of the
body, and by means of these the little creatures can wriggle
backwards and forwards. Refer to bluebottle grub, which the
children may have seen in meat.
The grubs eat greedily, and in a few days grow to their
full size.
Then the skin hardens into a case, and the grub seems
dead. After a time the covering (of the ' pupa ') bursts, and
a fly comes out.
THE ANT
An ' ant-hill.' — Find out the children who have seen an ' ant-
hill,' and ask them what they noticed. Bring out by questions
that ants, like bees, live together in large numbers ; that their
home is not in a hive, but underground ; and that when seen
underground they have no wings, though they are true insects.
Kinds. — ' ILozv many kinds of bees are there ? ' There are
the same three kinds of ants — the males, the females (or
queens), and the workers ; but a hive has only one female, while
an ant-hill may have several.
Wings. — All the ants the children saw in the ant-hill were
wingless, and the workers are always wingless ; but in the autumn
males and females have four wings, and leave the nest in thou-
sands. They choose their mates in the air, after which the
males soon die. Such of the queens as escape the birds snap
off their wings and start new homes.
Development. — The females lay eggs, out of which come
little grubs like those of the bee. The largest become females
Tlie Ant 163
and the smallest workers. They are all quite helpless, and
have to be tended by some of the workers. When the grub is
about to become an ant it spins a cocoon like that of the silk-
worm, only much smaller. Show if possible. Doubtless the
children who saw the inside of a nest noticed some of the ants
running about with these cocoons, and may have been told
(erroneously) that they were eggs. These cocoons must not be
too hot or too cold. When the day is warm they are taken
to the lower galleries of the nest [' Why ? '], and when the day
is cold they are taken up to get what heat they can from the
sun.
Food. — It is a mistake to suppose that ants store up corn
for the winter. They sleep through the cold months just as
bees do, and they could not eat corn if they had it.
Habits. — Give a brief account of some of the most interest-
ing habits of ants — their wars, their ' slaves,' their ' milking ' of
aphides, &c.'
THE SPIDER
[Place side by side large pictures of the spider and of some true
insect, such as the bee. It would be well also to have specimens
of the two creatures.]
The spider is not an insect. — By comparing the specimens
and the pictures bring out that the spider differs from the bee
(or other insect) in the following ways : —
(i) The bee has six legs, the spider eight.
(2) The body of the bee is divided into three parts — head,
chest, and abdomen — while the head and chest of the spider
make one part.
(3) The bee has four wings, the spider none.
There are two other very important differences, which the
children cannot be made to see : —
(i) The bee breathes through a vast number of little air-
1 The white ant, of whose destructive powers such extraordinary tales are
told, is not an ant at all. It belongs to the same order as the dragon-fly (the
Neuroptera), ^^■hereas the ant belongs to the Hymenoptera.
M 2
1 64
Longmans' Object Lessons
tubes which run to every part of its l^ody, and the spider
breathes by means of lungs. •
(2) The bee comes out of an egg and passes through a
number of changes, but the spider is born a spider.
Fig. 67.
For these and other reasons we say that the spider is not an
insect.
Claws. — Spiders hve on insects. Some kinds hunt their
prey, and others catch it in webs. All kinds kill it with poison.
The upper jaw has one or more pairs of claws with a small hole
in each. At the base of the jaw is a little bag containing
poison. When the spider catches an insect the pressure of the
jaws forces some of the poison into the wound. Compare to
the action of the fangs and poison-bag of a snake. The poison
of the spider is very powerful, and in hot countries there are
spiders which can kill a bird with a single bite, and can cause
much pain even to a man.
Web. — There are many kinds of webs — the house spider,
for instance, has a different one from the garden spider. Every
web is made of threads coming from the spider's body. Near
Tlie Spider 165
the tail are from four to eight small lumps called ' spinnerets,'
each full of little holes. Inside the body is a large bag filled
with a thick, clear fluid. When the spider wishes to spin a web
it squeezes a drop of this fluid through the spinnerets and
places it against the object to which it wants to fasten its line.
It then removes its body, thus drawing out the fluid into a
thread which is at once hardened by the air. The line is really
made up of a large number of threads, like our ropes. Describe
the construction of a web — say, the garden spider's. The
threads are very elastic, and covered with a sticky substance.
When a fly comes against the web it is caught there by this
sticky substance. The spider rushes from the centre of the
web or from its hiding-place, grasps the fly, turns it rapidly
round and round with its fore feet, covering it completely with
a broad silken band which makes it quite unable to move.
Then the spider kills it with a bite, and either eats it at once or
leaves it till needed.
If a wasp or other large insect is caught, the spider does not
venture near till the struggles of the captive have caused it to
be securely fixed in the web.
THE SNAIL
Shells. — Snails live in shells. Show. Procure empty
shells, and break one or two to show the internal structure.
Question on the use of the shell to the snail. If the shell is
entirely removed the snail dies.
The ' foot.' — The flat under part which can be seen when
a snail is out of its shell is the 'foot,' by means of which the
creature creeps. (See Fig. 68, a.)
The head. — Joined to the ' foot ' below, but partly separate
above, is the head.
Tentacles and eyes. — There are two pairs of feelers. Show
the action in a living snail. The hinder and larger pair has
eyes at the end. Show the advantage of having eyes at the
end of feelers which can point in all directions. Let the
i66
Longmans^ Object Lessons
children see from living specimen how the snail protects its
eyes by ' retracting ' and ' inverting ' them.
Fig. 68. — A, external characters
B, snail dissected ; a. t, an
terior tentacle ; col, collar ; in
mouth.
The Tongue. — The tongue of the snail, like that of the
other creatures of its class, consists of a long band covered
with roughnesses often called teeth. This band acts as a rasp
or file.
Breathing. — Just within the lip of the shell is a thickened
ridge called the ' collar.' (Fig. 68 a, col^ In this is an open-
ing leading to the organ by which the creature breathes.
Food. — Ask about the action of snails in a garden, and hence
elicit that they live on vegetables. They will, however, eat
their own dead.
Hibernation. — There is a dearth of food in winter, and
hence snails pass the cold months in a state of sleep. They
creep into crevices, or under stones, or under heaps of leaves,
which they stick together with their own slime. They draw
themselves into their shells and cover the mouth with a kind of
door. The snail arranges its ' foot ' so as to fill the opening,
pours out slime, mixes it with earth, and then withdraws its
Tlie Snail 1 67
' foot.' The cover soon hardens, and the snail sometimes
makes two or three more further in of slime alone.
Snails delight in warm, moist weather. They are always
active at night when the ground is covered with dew, and in
the day-time after rain.
In hot countries, where there is no winter, they sleep during
the dry season.
Eggs. — Snails lay eggs about the size of a pea. These
eggs are covered by a skin, and may often be found in gardens
just under the surface of the soil.
Edible snails. — The whelk and the periwinkle, which are
only sea-snails, are eaten, and there is no reason why the land-
snail should not be eaten also, as in fact it is in France and
Italy. The ancient Romans reckoned snails a great dainty, and
fattened them for the table. The feeding made them grow to
a great size, and an old writer (Pliny) says that three snails, two
lettuces, two eggs, a barley cake, sweet wine, and snow made a
good supper for himself and his friend.
THE EARTH-WORM
Lives. — The worm is adapted for living underground
(i) By its shape. Show a worm, and make the children
note that the head is pointed and that there are no parts
sticking out from the body.
(2) It has no legs. The mole, which also lives under-
ground, has very short legs.
(3) It is covered with slime. Let the children feel it.
This keeps the earth from sticking to the body.
Rings and motion. — The body of the worm is made up of
a large number of rings. Refer to the way in which a snake
moves. Though a worm has neither ribs nor scales it moves
in much the same way. Around most of the rings are set
eight little bristles. These can be felt as a living worm is
pulled backwards through the fingers, and they can readily be
seen with a lens. The bristles are curved and pointed. The
1.68 Longmans^ Object Lessons
worm moves by extending its body, seizing any roughness with
its bristles, and then contracting.
Food. — The worm hves chiefly on vegetable matter, especi-
ally decaying leaves. It swallows much earth, but this is the
only way it has of carrying to the surface the soil displaced in
making its hole.
Moutli. — The mouth is an opening under the first ring.
The worm drags its food underground, and before swallowing
moistens it with a kind of slime, which helps to digest it.
Senses. — Worms come up chiefly at night, and may then
often be found half-way out of their holes. If a light be
suddenly shown they withdraw at once, which proves that
though they have no eyes they are sensitive to light. They are
also very sensitive to any motion, even the breath of a spectator
being enough to make them retreat. They have no ears or
nose ; but they must have some sense of smell, as they can find
out favourite food and distinguish red from green cabbage.
They show fondness for carrot, celery, onion, and horse-
radish.
Uses. — Ask if the children have seen on lawns or in
meadows the curiously twisted little heaps of earth known as
' worm-casts.' These are the earth dug out by the worm when
burrowing, and, though gardeners dislike to see them, they are
useful as manure.
The passages made by the worm are also useful, as they let
in rain and air to the roots of plants.
The worm also does good by turning leaves and other
vegetable matter into manure, which it places beneath the
earth where it is wanted.
169
C : Lessons on Flowers
THE WALLFLOWER
[Provide enough flowers to let each child have at least two
perfect specimens. Let each child also have a slate or a piece of
paper divided by three horizontal lines into four equal parts.]
Calyx. — ' What is the iiajiie of this flower 1 ' ' Il'hat is the
name of this partV [The stem or stalk.] Notice that at the
top of the stalk and under the blossom there are some little
leaves. These seem to form a little cup for the blossom, and
are called the calyx.
Each of the little leaves forming the calyx is called a sepal.
' LLow many sepals has the wallflower 1 ' [Four.] ' What is
the colour of them ? ' In most flowers the sepals are green, but
in the wallflower they are often reddish. 'Are the sepals joined
to one another ? ' Let each child puU off the sepals, lay them on
the first division of the slate (or paper), and write underneath
them, ' Four sepals make the calyx.'
Look at the perfect flower and see how the sepals are
placed on the stalk. [One pair above the other.] ' Are the
sepals of the same size ? '
Corolla. — We now come to the blossom. Those who study
plants call this the corolla (a Latin word meaning a small
crown).
Each leaf in the corolla is called a petal (a Greek word
meaning a leaf). ' LLow many petals has the ivallfloiuer 1 '
[Four.] 'Are they joined to one another V Let children pull
them off, lay them on the second division of the slate (or
paper), and write underneath, ' Four petals make the corolla.'
Look at the perfect flower and see how the petals are
arranged. [They form a cross.] Notice the shape of the
petals. They look like leaves, each with a long white stalk or
claw and a broad, coloured blade.
170 Longmans' Object Lessons
Stamens. — You now notice a circle of little white threads
with powdery heads. Each of these is called a stamen (the
Latin word for thread). Let children pull them off carefully
and lay them on the third division of the slate (or paper).
' Were the stamens joined to one another t ' ' How many are
there ? ' [Six.] Write, ' Six stamens.' Notice the length of
them. [Four long and two short.]
Pistil. — ' What is noiv leftV This thickish green body
standing on the stalk is called the pistil because in many
flowers it is shaped like a pestle. Let the children pull off the
pistil, lay it on the fourth division of the slate (or paper), and
vfrite underneath, ' Pistil.'
Blackboard summary.
AVallflower.
Calyx = four sepals.
(i) Nearly of the same colour as the blossom.
(2) Quite separate.
(3) All equal.
(4) Two above, two below.
Corolla = four petals,
(i) Quite separate.
(2) All equal.
(3) Shaped like a leaf with a long stalk.
Stamens.
(i) Six (four long, two short).
(2) Quite separate.
Pistil.
[This lesson should be thoroughly revised till the children
are quite familiar with both the names and the things intro-
duced.]
Tlie Primrose 171
THE PRIMROSE
[Let each child have long-styled and short-styled primroses, and
a slate or paper divided by a horizontal hne into two equal parts.
Before beginning the last part of the lesson give out a wallflower
to each child.]
Two kinds. — ' What is the name of tliis floiver ? ' ' Show
tlie corolla.' ' Look at the centre of each.' ' Place on the upper
half of your slates [or papers) the floivers ivith little yellow points
in the centre, and on the lower half the flowers with little green
points in the centre.' ^ Pull the corolla ge?ttly aivay from the stalk
of each floiver in the upper division, and lay down the parts
in the division.' ' P)o the same with the flowers in the lower
division.'
Calyx. — ' Colour V [Green.] ' Number of points ?' [Five.]
' How many sepals, then 1 ' ' Are they separate or joined 1 '
[Joined.] Notice the puffed appearance and the five ridges.
Z^xo\\.Z,.—' Nicmber of petals r [Five.] ' Equal V ' Shape V
[Slightly divided at the top.] ' Try to separate one petal from
the rest' [They are united.] The lower parts form a tube.
Stamens. — ' Take up a corolla from the upper part of the slate
(or paper).' ^ Tear it so as to lay open the tube.' '■What do you
see at the upper part of the tube ? ' [Little yellow heads.]
' What are these 1 ' [Stamens.] ' Count them.' [Five.] ' What
do you notice about the length of them 1 ' [They are very short.]
'Now tear open a corolla from the lower part of the slate {or
paper.' ' IVhere are the stamens ? ' [In the lower part of the
tube.] ' Count them.' [Five.]
' Where are the stamens fixed in both kinds offloivers ? ' [On
the tube of the corolla.]
Pistil.— Cut or tear open a calyx from the upper division.
'What do you see on the stalk 2' [The pistil.] Point out
resemblance in shape to a pesde, mentioned in the last
lesson.
Now cut or tear open a calyx from the lower division.
Show the pistil. ' What is the difference between the pistils of
172
Longmans' Object Lessons
the two flowers cut open V [The pistil in the upper division is
short, and in the lower division long.]
^ Into how nia?7y parts may each pistil be divided?' [Three.]
(i) The little lump at the top of the flower stalk is called
the ovary.
(2) The thread running up from the ovary is called the
style.
(3) The little lump at the top of the style is called the
stigma.
Primroses are of two kinds —
(i) Short-styled (stamens above stigma).
(2) Long-styled (stamens below stigma).
Comparison with wallflower. — Work out the comparison,
which will give the following blackboard summary : —
WallJIowey
Primrose
Calyx . .
Reddish
Four sepals
Separate
Green
Five
United
Corolla .
Four petals
Separate
Five
United
Stamens .
Six
On stalk
Long threads
Five
On petals
Short threads
Pistil . .
The same in e\
ery
flower
Some short-styled, some
long-styled
THE BUTTERCUP
[Provide flowers as in the preceding lessons. Also, as in the
lesson on the wallflower, let children have slates or paper divided
horizontally into four equal parts. The number of sepals, &c. varies
very much in the different and even in the same species.]
Calyx. — ' What is the name of this flower ? ' ' Shoiv the
calyx.' ' How many sepals 1 ' [Five.] ' Colour ? ' [Yellowish-
green.] [Under the name Buttercup are included at least three
different flowers, all common. It matters little which kind is
Tlie Buttercup 173
taken, but note that the sepals are spi-eading or sharply curved
back according to the kind of flower taken.] Make the
children observe that the sepals are equal and quite separate
('free'). Let children pluck off sepals and place them on the
highest division of their slates (or papers), writing, ' Calyx ^
five sepals.'
Corolla. — '■ CohmrV "■ How many petals V [Five.] Have
the petals plucked off and placed on second division of slates
(or papers). ' Five petals = corolla.' Make children observe
that the petals are equal and quite separate ('free').
Petal of wallflower was like a leaf with a long stalk or claw.
Petal of buttercup is almost, but not quite, without stalk.
Stamens. — Have them plucked off and placed on the third
division of slates (or papers). Ask children to count them.
Answers will probably vary ; no answer will be under twenty.
In such cases the number of stamens is said to be ' indefinite.'
Stamen can be easily divided into two parts ^
(i) A thread-like stalk, called 2i filament (from a Latin word
meaning a thin thread).
(2) A yellow head, called the anther.
From the anthers comes a yellow dust, czS\s.A pollen.
Pistil. — Each of the little green points now left is the
stigma of one part of the pistil of the buttercup. Each part is
called a carpel.
Place them on the fourth division of the slate (or paper).
Count them. (Indefinite.) Write, 'Carpels (indefinite) =pistil.'
' Into how many parts did we divide the pistil of the
primrose V [Three — stigma, style, ovary.] The ovary and
style may be seen in each carpel of the buttercup. Inside the
ovary is a little body which becomes the seed.
Blackboard summary. — Recapitulate the lessons on the
Wallflower and the Primrose so as to bring out the table given
at the end of the second. Add another column with details of
the buttercup.
174 Longmans' Object Lessons
THE DEAD-NETTLE"^
Nettles. — There are two kinds of nettles growing wild in all
parts of the country — one, which stings when touched, and the
other, which does not sting, and is called the dead-nettle. The
latter has white or purple flowers. [The dead-nettle with
white or that with purple flowers will do for the purposes of
this lesson, though the white is preferable on account of the
larger size of its flowers.]
Calyx. — Green ; easil)' detached ; five sepals, united ; not
all of the same size.
Corolla. — Note the shape. The petals of the preceding
flowers were of the same size ; these are unequal. The corolla
is supposed to look something like a mouth with two lips \bi-
labiate]. The upper one, which bends over, has two divisions,
the lower one three. There are therefore flve petals (united).
Stamens. — The little hollow box which stands at the summit
of a stamen is the anther, and contains the pollen. The anthers
of the dead-nettle are black. By counting them it will be seen
that there are four stamens. The two outer and lower ones
are longer than the other two. The stamens, as in the primrose,
spring from the coralla tube, as will be seen if it is cut open.
Pistil. — Long, white, forked at the top.
Insects. — It is necessary that the pollen of one flower
should be carried to another. This is a task which insects
often unconsciously perform in their search after honey.
The peculiar shape of the dead-nettle facilitates the deposit in
one flower of the pollen caught on the body during a visit to
another. The stiff hairs placed inside the corolla tube are
supposed to be for the purpose of keeping small insects away
from the honey.
1 In this and the following lessons on flowers the same method should be
followed as in the preceding. Only the facts are given here.
TJie TtiHp 175
THE TULIP
[Illustrate with 'single,' not ' double' floweis.]
Calyx and Corolla. — The flower seems to have no calyx,
and the corolla to be made up of six equal petals not united.
These are arranged in two circles of three, the leaves of the
outer circle being placed opposite the openings between those
of the inner circle. When the calyx and the corolla are thus
alike they are called the perianth. (Gr. -n-ipi—peri — 'around,'
and dr6o