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Chicago
Public Schools
—TT–T-
A special Rep or t
of the Department of
C H I L ID STUDY
AND
P E D A G O Gº || C.
INVESTIGATION
ON
Children Atten ding
the Public Day-Schools
for the Deaf in Chicago
D. P. MacMILLAN, Ph. D.,
Director
F. G. BRUNER, Ph. D.,
Assistant
An Enlarged and Revised Edition of a Preliminary
Report Submitted to the Board of Education and
Printed on May 25, 1906


PUBLIC SCHOOLS
A SPECIAL REPORT OF
THE DEPARTMENT OF
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Child Study and Pedagogic
Investigation
ON
CHILDREN ATTENDING THE
PUBLIC DAY.SCHOOLS FOR
THE DEAF IN CHICAGO
D. P. MAC MILLAN, Ph. D.,
Director
F. G. BRUNER, Ph. D.,
An Enlarged and Revised Edition of a Preliminary
Report Submitted to the Board of Education and
Printed on May 25, 1906,
433677
tº NIVERSI’, ¥ tº F chºicAGO
LIBRAR}.S
266892
MARCH 1930
TABLE OF CONTENTS.
Page.
LETTER OF TRANSMITTAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
HEARING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
CLASSIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . II
SPEECH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I6
VISUAL ACUITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2I
PHYSICAL CONDITION:
Stature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ‘. . . . 25
Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Head Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Lung Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Strength of Grip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Grip Inder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Motor Ability . . . . . . . . . . * * * * * * * * * * is e º ºs e º 'º e º ºs º e º e º e ºs 4 I
Motor Inder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
MENTALITY:
Imitation and Suggestibility . . . . . . . . . . . . . . . . . . . . . . . . 48
Perception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
“4” Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Shot-sizing Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Lifted Weights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Amenability to Training . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
SUMMARY AND SUGGESTIONS . . . . . . . . . . . . . . . . . . . . 74 A d
LETTER OF TRANSMITTAL.
Chicago, October 12, 1908.
Mr. E. G. Cooley, Superintendent of Schools—
Dear Sir: I submit herewith a report on the deaf children
of the public schools of Chicago, and ask that a sufficient num-
ber of copies be printed at the earliest convenience. The subject-
matter has been on our hands now for a long time, and on ac-
count of the large number of requests for the information col-
lected by us, as well as the intrinsic interest and value of this
data for our teachers in service, I believe the whole subject ought
to be put in available form for use.
An account of our dealings with the special study of the deaf
children is given in a formal way in this letter of transmittal to
you.
The attention of the Department of Child Study and Peda-
gogic Investigation was first officially drawn to deaf children in
the public schools of Chicago by action of the Board of Educa-
tion at the opening of school in September, 1902. At this time
the Superintendent of Schools placed the matter before the
Committee on School Management, and on September 3, 1902,
the minutes of the Board indicate the following course of
action:
“The Committee on School Management reports that there
are in the School for the Deaf Mutes quite a number of children
who might be more properly taken care of in the schools for the
feeble-minded. As the task of separating the feeble-minded
from the normal children in these schools is a delicate one, the
committee recommends that the Superintendent be authorized to
employ the teachers in the Child Study Department to aid him
in determining whether they should be excluded from the public
schools or not.” (Proc. 1902, Page 70.)
A report on these children was submitted to the committee
On October 2, 1902, which showed that a psycho-physical ex-
amination had been given to 160 pupils in the rooms for deaf
children, among whom were found I6 children who were notice-
ably or markedly subnormal in mentality and were accordingly
4 LETTER OF TRANSMITTAL
recommended for exclusion from the public schools. Since that
time it has been the policy to have each child undergo a psycho-
physical examination by the Department of Child Study, as soon.
as the parents of the child make application for his admittance
to these rooms for deaf children. In two or three instances the
Supervisor had been prevailed upon to admit to these rooms,
when the classes were exceptionally small, certain children who
were practically deaf for ordinary school exercises and afflicted
with speech defects, for the reason that they would gain excep-
tional benefit from the kind of training which the teachers of
these children alone could give.
On account of the time-worn contention among parents of
deaf children as to the relative superiority of the lip-reading or
oral and the manual methods of teaching the deaf, and especially
as to the alleged non-adaptability of the oral method to any
children except those of more than ordinary brightness, and to
those with some power of hearing, it so happened that the whole
matter was again brought before the Committee on School Man-
agement at the beginning of the School year 1904-1905. No
definite action was taken by the Board until the following
communication was received October 26, 1904, from one of its
members which finally was effective in bringing about the more
comprehensive and formal report herein embodied.
“. . . Since the last meeting I have visited several deaf and
dumb schools, and I found them very much neglected. In one
case I found two children who were not deaf or dumb, and had
no right to be placed with these children. I also found at least
thirty or forty per cent of the children under normal, as well as
deaf and dumb, and was informed that teaching these children
the oral system was a waste of time on account of their impaired
mental condition. I also found teachers with classes so large
that it is impossible for one teacher to make progress with all
the children—naturally more attention was given to the brighter
children and the others were neglected. Therefore I think it
the duty of this Board to thoroughly investigate the entire mat-
ter and where there are children who cannot learn the oral sys-
tem, the combined alphabet or the sign system should be taught
in special rooms in schools other than where the oral system is
LETTER OF TRANSMITTAL 5.
taught. I also think more time should be given to the teaching
of reading, writing and arithmetic, as these studies seem to me
to be the most essential to a deaf and dumb person. . . I trust
your honorable body will give the matter the most thorough con-
sideration and investigation, as this department of the public
School system is much neglected and should have a thorough
reorganization, better rooms, more teachers and more attention
in general given to the children afflicted by the loss of hearing
and speech.”
On January 18, 1905, a committee consisting of the Super-
intendent of Schools, the Director of the Child Study Depart-
iment and three medical inspectors was appointed to investigate
the whole matter and to report its findings to the Board of Edu-
cation. In accordance with the usual routine of such matters
the whole inquiry was referred by the Superintendent of Schools
to the Department of Child Study and Pedagogic Investigation,
and on April 12, 1905, a brief summary of the results was sub-
mitted in a preliminary report. The only action taken on the
matter at this time was to refer it back to the investigators with
instructions to present the data in detail. The final report herein
submitted was placed in the hands of the Superintendent of
Schools, subject to call from the Committee on School Manage-
ment, which demand finally was made on May 25, 1906, where-
upon it was ordered printed at once, and copies distributed
among the members of the Board of Education and educators of
the city.
The original form in which it was printed by the Secretary
of the Board was, in certain features, abbreviated and popular-
ized and as such it fulfilled a temporary and local service, but
owing to the large number of requests for copies and inquiries
from school boards of other places, from educational governing
bodies and from professional and general libraries in this and
other countries, as well as the desirability of placing our re-
sults in permanent form for our teachers, it seems highly advis-
able to print the whole subject-matter in a form which will more
adequately meet the larger demand.
Very respectfully yours,
D. P. MAC MILLAN, Director.
EXPERIMENTAL STUDIES OF DEAF
CH!LDREN.
It is doubtful if more than a very small minority of persons
who have not had intimate dealings with deaf children are
familiar with the characteristics which differentiate this special
group from hearing children. One meets with all sorts of opin-
ions and notions concerning their capabilities or incapacities.
It is held by some that the senses of deaf children, other than
hearing, are exceptionally acute, and again the assertion is made
that children who are defective in one sense are deficient in all
the senses and for this reason they speak of the mind of the deaf
child as of a distinctly lower type.
This study is not, indeed, concerned with all the deaf child-
ren in Chicago, nor with all deaf children of School age. It
deals with deaf children attending the public day schools whom
this department considered of high enough grade of mentality
to be educable by the special class methods of the public schools
for the deaf. These deaf children have been admitted into these
special rooms of instruction upon recommendation, after being
subjected to a careful psycho-physical examination to determine
their mental status and the degree of hearing power which they
possessed. The feeble-minded and those of extreme sub-normal
mentality are not incorporated in our results. It was, then, our
object to carefully examine and estimate the comparative physi-
cal and mental status and to make an extended study of the
progress and school conditions of the deaf children in the public
day Schools of Chicago.
Some three months were devoted to this study. Children
were taken in groups of two or three in a private room in which
conditions were similar to those of the classroom, and in all
about one or two hours was given to each child. This length
of time was found necessary on account of the difficulty of get-
ting responses from this class of children, who are naturally so
excessively timid and hesitant in manner. This it is natural to
3 EXPERIMENTAL STUDIES
expect on account of the difference in their social life, which
is usually confined to intercourse with parents, teachers or
children similarly afflicted. Experience has shown that one must
have at least a half-hour's intimate association with any child
before he can be reasonably sure that the responses secured are
anything at all like normal, and that the estimate made of the
child's mental efficiency is not totally erroneous. If this be true
of children in general, it is so true as to be axiomatic when deaf
children are the subjects of examination. To estimate the men-
tal status or educational possibilities of the deaf child requires
not only special knowledge of their habits and characteristics,
but also considerable intimacy with their environment and social
conditions. A cursory examination will very frequently lead one
to adjudge a child as of sub-normal mentality, whereas a greater
familiarity with the disparities and mental traits of this class of
children will enable one to Secure surprising results. It was
found advantageous, in order to overcome the reticence of these
children, to make the first examination brief and preliminary,
So that the children might become personally acquainted with the
examiners and confident in all their modes of expression.
In order to investigate the hearing and speech possibilities
and progress of deaf children, it is indispensable that we have
Some knowledge of the sensory, nervous and bodily conditions
which are intimately related to both hearing and speech. Thus,
it is necessary to know something of the sight, as good vision
is necessary to good lip-reading. It is necessary to know
whether the defect in hearing is local or whether it is due to gen-
eral lack of sensitiveness. Likewise it is of value to know
whether the deaf child is less or more sensitive to impressions
of touch, weight, etc. In case these senses are obtuse, one might
well conclude that the deficiency in aural acuity is primarily due
to general dullness of the whole psychical system. If the other
senses are acute, the defect is probably due to the organ of
hearing and not to obtuse mentality. To acquire speech it is of
the first importance to have good organs of speech. The nose
and throat must be open and free. The naso-pharyngeal cavity
must be examined for enlarged tonsils and adenoid growths.
Something must be known of the hard and soft palate in their
DEAIF CHILDREN 9
relation to middle-ear deafness and breathing power, as well as
the condition of the tongue, both as to structure and mobility.
The general nervous condition of children very markedly in-
fluences their speech and mental ability. The same nervous con-
'ditions which induce such defects as stammering, stuttering, hes-
itancy, lisping and lalling are as likely to occur in deaf children
as in hearing children. Then, too, there are such nervous affec-
tions as chorea, nervous inertia and general incoordinations.
These especially influence mentality and speech.
The report of the Child Study Department for the year 1899–
1900 showed that those children who were larger, stronger
quicker and better nourished were mentally superior to those
who were not so well developed. The same conditions which
favor physical superiority are found to have a like or comparable
influence on the mental side. It therefore to a degree not only
affords a convenient but a serviceable cue to the mental status,
to know how deaf children compare in size, strength, quickness,
sensory and motor defects with hearing children of the same
age. In the case of a child having no language, it is difficult to
gain much information directly of his mental ability. It is, how-
ever, possible to measure his efficiency in such simple processes
as perception, and, in case a child possesses a few symbols, it is
possible to learn something of his immediate sense memory. It
was our aim to employ only simple tests to study all these various
phases of the sensory, physical, nervous and higher mental life
of these children, in order to secure cumulative evidence of
the exact nature of their hearing defects and of their mental
and physical conditions as these are related to the acquiring of
speech and school training.
HEARING.
METHOD OF CONDUCTING THE TEST.S.
Three instruments were used in the examination of hearing
power:
First: The Audiometer. The instrument used was an
ordinary Seashore audiometer. This is, in brief, a simple elec-
trical apparatus for producing a measurable noise, which is
brought about by the making and breaking of a secondary cur-
rent. This noise is transmitted to the ear of the person tested
IO EXPERI MIENTAL STUDIES
by a telephone receiver held tightly against the ear. The child
is tested with his back to the examiner and with eyes closed.
The instrument was devised for testing differences in aural .
acuity of persons not ordinarily considered defective in hearing.
In many cases its range is too limited for grading hearing power
when this power is not of sufficient acuity to detect speaking
tones of the human voice. The hearing power of children can be
conveniently graded according to the norms for hearing acuity,
worked out with normal children and already reported on. (See
Report No. 2, Department of Child Study and Pedagogical In-
vestigation.)
Second: “Snapper.” This little instrument when snapped
between the forefinger and thumb, makes a mechanical
snap of sufficient loudness to be heard by the human ear
of average acuity in a quiet medium at a distance of about 500
feet. It is held by the experimenter slightly behind the ear of
the child examined, out of range of vision either direct or lateral,
and the child is asked to count the clicks, or in case of the
younger children, the starting of the body entire, and the super-
ficial reflexes, especially the conjunctival, are observed. By
this means the hearing power of certain children could be gauged
who could not be reached by the more delicate instrument.
Third : Differential Tube. This piece of apparatus consists
of a tube of soft rubber whose internal diameter is 4 mm. and
whose length is IOO cm., fitted with hard rubber ear pieces to
be inserted into the ears, one end into the child’s ear and the
other into the ear of the examiner. This ear piece was held
firmly between the first finger and the thumb, and care was taken
that the stimulation was not communicated through the sense of
touch. A tuning fork of pitch “a” was struck on a hard sub-
stance and its base applied to the tube. First, in order to famil-
iarize the child with the sound, the fork was struck briskly on a
hard object and its base placed on the child's front teeth. Only
after the child became somewhat familiar with the sound thus
conducted, was recourse had to air conduction. This instrument
proved adaptable for testing hearing power of even lower grade
than the snapper, owing largely to the fact that the stimulus
had a greater duration, thus affording a better opportunity for
the element of attention to enter. *
DEAF CHILDREN II
This work with instruments was further supplemented by
tests made with the human voice in ordinary speaking tones and
in shouting, taking care when within close range that the child
was made as nearly as possible dependent upon the Sense of
hearing.
CLASSIFICATION.
The hearing ability of this group of children somewhat con-
veniently is divided into five classes. This division is purely
conventional and practical inasmuch as it is formulated wholly
on the basis of school room efficiency and the value which must
be attributed to the power of hearing in its relation to the acqui-
sition of oral speech.
In the first column, Class I, are shown the pupils who are
totally deaf-insensitive to the strongest Sound vibrations which
we had any means of employing.
In the second column, Class 2, are presented those who are
practically deaf, i. e., only Sounds which are continuous and most
intense can be heard. It is very probable that their hearing can
never be developed sufficiently to hear the human voice even with
the assistance of mechanical devices.
In column three, Class 3, is given the number of those child-
ren who possess a degree of hearing power—they hear loud
sounds, but yet they have not sufficient sensitivity and control
of hearing to understand vocal speech. The children of this
class offer hope that with the assistance of mechanical devices
for intensifying the voice, their hearing power may be developed
So that advantage may be taken of this normal means of ac-
quiring spoken language.
Class 4. Those pupils who are deaf for Ordinary School
conditions, are placed in column four of the table. In general,
the pupils of this class hear only words spoken loudly and close
to the ear and are therefore to be considered as deaf from the
point of view of conditions that ordinarily prevail in the school-
room. They do, however, possess sufficient hearing to assist
them in acquiring speech when appeal is made to their under-
standing through this sense avenue.
In column five, Class 5, is listed a certain small number of
hearing children who were temporarily in the rooms for the
I2 EXPERIMENTAL STUDIES
deaf and who are greatly in need of the training in articulation
which it is not possible for them to get in our School system,
except from teachers who have had special training in the rudi-
ments of voice culture.
TABLE I.
TPOWER OF HEARING.
Class 2.
Practically Class 3. Class 4. Class 5.
Schools Class 1. Deaf. Hear Hear loud Deaf for ordi- Hearing chil-
Totally only most in- |noises but can-| nary school | dren. In deaf
Deaf tense continu-jnot hear speech purpoSeS rooms for speech.
ous sounds training
Holden. . . . . . . . . 2 1. 2 5 O
Beidler. . . . . . . . . 2 0 0 1 0
Burr. . . . . . . . . . . 5 1 7 2 2
Clarke. . . . . . . . . 2 2 4 1 0
Darwin . . . . . . . . 10 4 8 3 2
Dore . . . . . . . . . . . 1 2 0 6 I
Froebel . . . . . . . . 4 1. 0 1. 0
Hammond. . . . . 3 2 3 0 O
Kozminski. . . . . 1. 1 4 0 O
Normal . . . . . . . . 2 1 3 1. 0
Ogden . . . . . . . . . 7 8 5 O 1
Seward . . . . . . . . 4. 2 0 1 O
Yale. . . . . . . . . . . 11 8 17 5 2
Totals. . . . . . . 55 33 53 25 8
Total number examined. . . . . . . . . . . . . . . . . . 174

Although thus classified, it must not be assumed that these
children will always retain the exact relative order here pre-
sented. With some the hearing power deteriorates, while the
hearing power of others will show marked improvement owing
to their general mental training in giving attention and in
attaching significance to excitations of this sense organ. Even
among those congenitally defective in hearing it must not be
assumed that the hearing power will always remain stationary.
Some children were in the deaf rooms who were regarded as born
absolutely deaf and now at the age of fifteen or sixteen are
able to hear conversation. This improvement usually accom-
panies the great growth changes at the periods of second denti-
tion and of puberty. There are certain children with varying
degrees of deafness whose hearing has gradually improved; there
are other cases of deafness in which there is apparently no
improvement. The congenitally deaf, however, form, as far as
we are able to determine, only about 50 per cent of the total
number, but it is difficult to draw a hard-and-fast line of de-
markation between congenital cases and deafness as one of the
DEAF CHILDREN I3.
sequelae of disease. Many parents assign very insignificant causes
for this affliction. In many other cases it is impossible to deter-
mine just when deafness did occur, especially since scarlet fever,
spinal meningitis and other febrile diseases sometimes are ex-
perienced during the first year of the child’s life before speech
develops, and deafness is attributed to these, whereas as a
matter of fact, it antedated them. The two most frequent.
maladies which leave deafness as one of the sequelae in their
wake, as suggested above, are scarlet fever and spinal menin-
gitis. The significance of this is manifold in that very frequently
some tendency to mental aberration is also present, together with
nervous disturbances and inco-ordinations. Although not feeble-
minded always, these children so afflicted would be far below
the normal in mentality even were their hearing normal. It is
a matter of observation that deafness which occurs as a result
of disease is as frequently attributed to some catarrhal condi-
tion of the middle ear, atrophy of the ossicles of this region,
or degeneration of the typmanic membrane, as to some internal
ear trouble or lesion of the brain. Sometimes these diseases
cause absolute loss of hearing. In other cases there is but slight
diminution in auditory acuity. In every case it is very desir-
able to know just where the defect lies, as well as the degree of
deafness, in order to classify the child and suit his school train-
ing not only to his present status but also to his future needs.
Reference to Table I will show the relative proportion of
children in each of the five classes. In the first class there are
55; in the Second, 33; in the third, 53; in the fourth, 25. Were
the number examined very large, extending into the thousands
instead of 178, we might reasonably expect to find an equal
number of children in each class; that is, experimental evidence
goes to show that there are varying degrees of deafness, rang-
ing all the way from slight and temporary impairment
of hearing due to a cold, to the stage of absolute and permanent
silence. This, of course, necessitates some practical standard by
which one must judge whether a child's hearing is sufficiently
poor to justify his being assigned to the the rooms for the deaf.
Where the recommendation has been made by the Child Study
Department, the criterion has been a practical one, based not
I4. EXPERIMENTAL STUDIES
alone upon the child's absolute power to hear, but also upon
his inability to carry on the work successfully in the rooms with
hearing children. However deaf a child might be, he was never
recommended for the deaf classes as long as his progress in the
rooms with hearing pupils was satisfactory. Likewise in those
cases where the defect was more largely one of mentality in-
stead of defective hearing it has been the policy of the Child
Study Department to recommend that the child be excluded from
the rooms for the deaf. The above criterion seems the only one
usable in actual practice.
Among normal hearing children, speech is an instinctive ac-
quisition which shows itself at a relatively definite time in mental
ripening. The activities and speech of all persons in the home
are a constant appeal to the young and yearning listener, and
so there come to be set up mental associations between his acts
of hearing and his vocal responses. The activities of seeing,
hearing, touching, etc., which at first Operate somewhat inde-
pendently of each other, come to be firmly and constantly con-
Inected, so that one sense organ-act stands for the activity of
another sense-process or group of such processes. Seeing comes
to stand for touching. Hearing means doing or going to do.
The child hears his own prattle as well as the speech of others
about him. Others attribute meaning to his spontaneous bab-
blings and his special acts, and, in the initial steps at least, his
acts are named for him. These activities in which he indulges
and to which others give specific values and names, are at first
gross and inchoate, with meanings as vague, but gradually become
with his growth of consciousness, more definite and precise. In
this way a certain word or name heard is associated with some
object reacted upon and the child's natural babblings are made
to conform to the word heard. Thus the child, through his
Own hearing and with very small effort, catches the cues which
lead to his articulation of the words he has heard spoken by
those about him. But with the deaf child, the process of acquir-
ing speech is by no means so simple. No sounds are heard, or
if sensed at all, are heard very indistinctly, so that the procedure
becomes one in which intense and concentrated attention is nec-
essary to succeed at all.
DEAF CHILDREN I5
The most direct inherited associations are between speech
and hearing, and not between speech and sight, as must be the
procedure in the case of those whose power of hearing is ab-
sent or very defective. It is always very difficult to divert na-
ture's course, but this does not imply that it is never advisable
as exigencies arise to modify her laws or methods of procedure,
When limitations have been set to one group of associations, it
is absolutely indispensable to form a new set of associations if
training of any part is to take place, and this re-direction of an
instinctive procedure is not accomplished without considerable
effort. Intercourse between individuals is possible only by some
language medium, and a language medium implies some Sort
of symbols which refer directly to objects, activities or events,
and it further implies that the symbols used have a commoir
meaning to all using them.
All articulatory symbols of intercourse are relatively arbi-
trary and conventional, and their expression must occur either,
as is commonly the case, by the natural way of imitating with
the vocal mechanism what is received through the auditory appa-
ratus—in which case the symbols are expressed spontaneously—
or the meaning of these symbols must be consciously acquired
and their expression laboriously worked out, as in the case of
the deaf. In the latter there must occur a definite adjustment
of mouth-parts and chest activity on the one hand, or the
manipulation of the hands on the other, according as the vocal
or manual language is used. One must be learned as well as
the other. The selection and preference of one method over
another, must be decided on other than psychological grounds,
inasmuch as psychology properly defined, deals with a descrip-
tion and explanation of all mental processes, and so every men-
tal reaction, the true and serviceable as well as the false and
trivial, must have its history as to its origin, characteristics and
function. Both utility in social relations and facility or ease
of acquirement must largely determine whether one or the
Other method of training the deaf shall be used in the school-
1 OO111.
There is the further question as to whether the manual
method has certain limitations as compared with the oral in
I6 EXPERIMENTAL STUDIES
developing the mind. But this is a question that must be de-
cided, for the present at least, on theoretical and philosophical
grounds. Thus far there have been no scientific investigations
on adults, trained by these two methods, which might tend to
show that the range of expressive thought is greater or less in
one method than the other. The philosophical problem is one
that does not concern us here, for it leads to nothing more than
the expression of an opinion, and offers no hope for the solution
of the question.
SPEECH.
There are found in the rooms for the deaf, children who had
no speech when deafness occurred. There are others who had
learned to speak a little, and again, there are a few others whose
deafness appeared after five years of age and who possessed con-
siderable power of speech. It obviously would not be just to
group all these together. Therefore the children are distrib-
uted into three groups on the basis of their capacity for appre-
ciating and using speech, taking into account the time they have
been receiving instruction. We have then as a mater of fact
the following groups: (1) those whose speech is normal or
nearly so; (2) those whose speech is defective either in the
quality of tone of the vocal sounds or in the articulation of the
consonants, nasals, labials, sibilants, etc.; and (3) those who have
no speech or are incapable of uttering intelligently at least fifty
words. Of course all children who had lost their hearing be-
fore they had learned to talk would be in group 3 on first en-
tering school.
The problem, then, is that of determining the character
of the speech that has been acquired for the different periods
that the children have been in school. In keeping with this,
the children in the various rooms have been distributed accord-
ing to their efficiency in speech after they have been in school
three, five, seven and ten years. It must be borne in mind that
these groups do not include all the children in the rooms for
the deaf, since obviously there is a large number of them who
for various reasons have not been in school for as long a period
as three years. Furthermore, not only must the length of time
the pupil has been in school be considered but also his condition
DEAF CHILDREN 17
on entrance into school. Under those three groups, therefore,
of children whose speech is normal, whose speech is defective,
and those whose speech is practically wanting, it was thought
advisable to indicate the following (See Table II, p. 19):
I. Children who have sufficient hearing to assist them in
acquiring speech.
II. Pupils whose hearing was lost after the age of five
years—i.e., after quite a degree of facility in speech had been
gained before deafness occurred.
III. Pupils who lost hearing before five years of age—i. e.,
where an opportunity had been afforded for the loss of auditory
imagery and the fading of muscular habits associated with
articulation and phonation.
IV. Those born deaf, or those in whom the loss of hearing
occurred so early in life that speech had never been acquired.
THREE YEARS IN SCHOOL.
Of deaf children who have had speech training for no longer
than three years, we can make the following summary:
24, speech normal, or nearly so.
23, speech more or less defective—i. e., have considerable
speech, but the articulation or tonal quality of the voice is more
or less defective.
7, Speech wanting—i. e., from the practical standpoint, little
or no speech.
It must be understood that where speech is herein spoken
of as more or less defective, the child can usually be easily un-
derstood by almost everybody, and in all cases can be under-
stood by those who are accustomed to associate with him, though
his voice, to be sure, is unpleasant and unnatural.
Of these twenty-four whose speech was found to be normal,
it is interesting to learn that six children possessed some usable
remnants of hearing, while 18 were deaf. Of the 18 deaf at
least IO had lost their hearing after the age of five years, leav-
ing only 6 who were afflicted with deafness before the age of
five and 2 congenitally deaf. That is, we may say, that normal
speech had been taught to 8 of the 54 children by the indirect
method during the brief period of three years.
Turning to the 23, whose speech was understandable but
I8 EXPERIMENTAL STUDIES
somewhat defective, the data show, that 3 had some hearing
and 3 had lost their hearing after the age of five, 9 deaf chil-
dren had lost their hearing earlier than the age of five and 8
were born deaf.
Of the 7 who possessed little or no speech ability after
three years in school, none had ever had hearing to be of any
service in the acquisition of an articulatory language, 4 having
been congenitally deaf and 3 having lost their hearing early in
life.
To summarize then if we exclude from consideration first,
those who have sufficient hearing to assist them in acquiring
speech and those who lost their hearing after five years of
age, which two groups obviously form a separate class, we have
remaining those who lost their hearing before the age of five and
those who were born deaf. Of these we find :
8, normal speech.
I7, speech more or less defective.
7, Speech wanting.
FIVE OR SIX YEARS IN SCHOOL.
Turning now to the children who have been in school five
or six years, we find the cases distributed as follows:
I3, speech normal.
I4, speech more or less defective.
O, Speech wanting.
Considerable interest attaches to a comparison of the make
up of the children of these three groups with those of three year
School instruction. (See Table II.) Whereas, among the lat-
ter but 8 of 24 with normal speech had lost their hearing earlier
than five years, or were congenitally deaf, of those with 5 or 6
years of School instruction, IO of the 13 belonged to this class;
all of those with somewhat defective speech had lost their hear-
ing early in life; and no child of 5 and 6 years’ school instruction
Was found without speech sufficient to communicate his simpler
needs.
Again to summarize the results, excluding as above, that
special class comprising those who have some hearing and those
who lost their hearing later than the age of five, we have those
DEAF CHILDREN I9
classified as born deaf and having lost their hearing before the
age of five—of these there are:
IO, speech normal.
I4, speech more or less defective.
O, Speech wanting.
SEVEN OR MORE YEARS IN SCHOOL.
Taking up those children who have been in school seven or
more years, we find the following distribution. (See Table II.)
I3, Speech normal.
9, Speech more or less defective.
o, Speech wanting.
One boy among those with normal speech had hearing and
was temporarily given a place in the rooms for the deaf to rem-
edy his very defective articulation. Of the remaining I2, only
2 had lost their hearing later than five years, 2 were deprived of
their hearing before the age of 5 and 8 were congenital cases.
One only of the 9 with somewhat defective speech had lost
his hearing later than 5, 3 before the age of 5 and 5 had been
deaf from birth.
TABLE II.
ABILITY TO USE SPOKEN LANGUAGE.
Table showing the power of speech possessed by children of different degrees
of deafness, who have received speech training for three, five, seven, and ten
years respectively.

Hearing Deaf
Character of Time in sufficient
speech School to aid in Hearing Hearing Con
acquiring lost after | lost before it *
speech. the age of the age of '. #
five years | five years €3.
3 years. . . . . . . . . . . . 6 10 6 2
Speech normal, or 5 or 6 years. . . . . . . 3 0 7 3
nearly So. 7 years. . . . . . . . . . . . 0 2 2 5
10 years or more... 1. 0 0 3
Speech somewhat 3 years. . . . . . . . . . . . 3 3 Q 8
defective, either in 5 or 6 years........ 0 0 4. 10
quality of tone or 7 years. . . . . . . . . . . . O 1. 3 5
articulation of sounds.'10 years or more... 0 0 0 0
w 3 years. . . . . . . . . . . . 0 0 3 4
Speech wanting, 5 or 6 years........ 0 O 0 O
or less than 7 years. . . . . . . . . . . . 0 0 0 O
50 words 10 years or more... 0 0 O O
Totals. . . . . . . . . . . . . . . . . . . . . . . . . 13 16 34 40

Taking into consideration then the acquirement of speech as
it is related to time of instruction, we find of the whole number
of IO3 children who had had at least three years School training,
2O EXPERIMIENTAL STUDIES
that 96 succeeded in acquiring oral speech, of whom 50 possessed
normal speech and 46 were able to interpret oral language, but
to speak albeit with difficulty or slight defect. It will be seen,
moreover, that of this whole number there are I3 children who
possessed sufficient hearing to enable them to be materially as-
sisted in acquiring speech under schoolroom conditions. Of the
children who must be classed as deaf, I6 lost their hearing after
the age of 5 years; 34 were deprived of their hearing before the
age of 5 years, while there are 40 whose parents gave evidence
regarding their early lives which indicated that in all probability
these children were born deaf.
Although 7 children were found whose speech was wanting
after a period of training of 3 years, there were none after a
school period of 5 or more years who were not able to express
themselves more or less intelligibly.
Not considering those who lost their hearing later than the
age of 5, and those who have considerable hearing, 23 had voices
which were unpleasant and unnatural after three years of school
training, I4 after five years and 9 after seven or more years.
These comparisons are made with reference to the voice of the
normal child as a standard and are obviously unfair to a child
working under the limitations of the deaf. It would no doubt be
better to use a criterion of practical utility rather than one of
esthetic value, but it is impossible in the case of the former to
arrive at any norm for comparison, and hence we are forced to
the use of the apparently less practical standard of reference,
which, nevertheless, has, as a matter of fact, considerable signifi-
C311Ce.
The time that a child has been in school is not the only nor
is it the most important, factor in effecting speech efficiency.
The natural endowment of the child is an extremely important
consideration. Next stands the environment, some of the most
important factors of which are the character of the food which
the child receives, and the regulation of his rest and exercise.
It is further of significance whether the parents speak the lan-
guage of the school and are thus able to give the child some
drill in the exercise of his speech outside of school hours, or
in case the parents do speak the language of the school, whether
they have the time and inclination to thus co-operate with the
DEAF CHILDREN 2I
teachers. An attempt was made to evaluate all these factors in
the study of the condition of each child, and formed part of the
basis for the specific recommendations which were given to the
child’s teacher at the time he was examined with reference to
his school possibilities and the best line of treatment adapted to
His particular needs.
VISUAL ACUITY.
TABLE III.
VISUAI, ACUITY.
Tables showing the distribution of deaf and hearing children, respectively,
as regards the visual acuity of both eyes, whether the vision of the two eyes
is the same or different.
DEAF CHILDREN.
1.00 or 0.40 of nor-
tº gº 0.67 of nor-0.50 of nor- e
Vision better. Nor- mal. 20–50 Blind
mal mal. 20-30 || mal. 20-40 or less
The vision of both eyes being .. 225 35 21 2 0
The vision of one eye being
1.00. the other. . . . . . . . . . . . . . . . . . . . . . . . . . 22 9 3 5
The vision of one eye being
0.67, the other. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4 O
The vision of one eye being
0.50. the other. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 S
Total number examined, 353.
E[EARING CHILDREN.
1.00 or 0.67 of 0.50 of 0,40 of #. Blind or
Vision better, normal. normal, normal, "ºo * nearly
Normal 20–30 20-40 20-50 or 1 SO
e S
The vision of both eyes being.. 972 82 11 27 69 0
The vision of one eye being
1.00, the other. . . . . . . . . . . . . . . . . . . . . . . . . 119 8 11 21 4
The vision of one eye being
0.67, the other. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 18 20 1
The vision of one eye being
0.50, the other . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 7 0
The vision of one eye being
0.29, the other . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 0
Total number examined, 1,436.
The Oral method of training the deaf implies not only the
utterance of speech, but also speech-reading. With normal hear-
ing children this is done through the medium of the ear, where-
by even the slightest variation of tones and inflections are in-
terpreted naturally and without effort, yet each carrying with it
a significance that differentiates a shade of meaning.
Though the eyes are always used in discerning the attitude
of the speaker by the hearing child, the use of these organs plays
a subordinate role. Not so with the deaf child. Every idea
scommunicated to him, except the few he gets through touch, taste
22 EXPERIMIENTAL STUDIES
and smell, must reach him through his eyes. In interpreting
speech he must observe the most minute movements of the mouth-
parts, the eyes and facial muscles, to interpret their significance,
translate them into ideas and observe shades of meaning by
the slightest variations in muscular adjustments and movements.
Hence the condition of the deaf child's vision becomes a very im-
portant consideration. While there are many opportunities for
relaxation of the eyes of the normal child, these opportunities
are obviously less frequent in the case of those children who
have to depend on their vision almost entirely. Defective vision,
therefore, tends to produce greater limitations among the latter
than the former.
In Table III are given the distributions of deaf children and
of normal hearing children, from comparable Social environments
and home surroundings, as regards visual acuity. In this the
emphasis is laid on the function of vision as a determining factor
in acquiring school information. It is well known that a child
may have very defective vision in one eye and yet because the
other eye functions normally, the child may not be seriously
handicapped in receiving impressions from his surroundings.
Accordingly the acuity of each eye is registered separately and
the number of children is recorded who have good vision with
both eyes as well as the number of those who are visually acute
with one eye and defective in the other, or indeed, those who
have poor vision with both eyes.
In the upper half of the table is recorded the distribution of
353 deaf children and in the lower half a similar distribution
of I,436 hearing children. Looking at the upper half of the
table for a moment (the part referring to deaf children) it is
seen that in the first line, beginning at the left, are tabulated;
first the number of children with normal vision in both eyes
(225); then the number whose vision for both eyes is o.67 nor-
mal (35); O.50 normal (21); and O.4O normal (2), respectively.
In the second line is shown the number of deaf children whose
vision for one eye only is normal, while that of the other is o.67
normal (22); O.50 normal (9); O.40 normal (3); and where
the vision of one eye is wholly wanting (5). Then in the third
line follows the number whose vision in one eye is o.67 normal,
DEAF CHILDREN 23
as registered from the vision chart, while that of the other eye
is O.50 normal (II); O.40 normal (4); and vision entirely want-
ing (o). This will suffice to make the whole table easy of in-
terpretation.
From the distributions in the table it is thus seen that of the
total number of deaf children from whom we have visual acuity
records (353) there are 225 or 63.7 per cent whose vision
is normal as judged by the standards of the optician or occulist.
Two hundred and sixty-four of the 353 or nearly 75 per cent
have vision of at least one eye normal according to the same
standards, and nearly 90 (88.9) per cent have at least one eye
whose visual acuity is O.67 normal.
It is of interest and significance to compare the visual acuity
of deaf children with that of the 1,436 hearing children in the
lower half of the table. About 3 per cent fewer of the deaf
have the vision of both eyes normal. Four per cent fewer have
vision of at least one eye normal, but almost 2 per cent more of
the deaf have a visual acuity of both eyes O.67 normal or bet-
ter, as compared with their hearing companions. Certainly of
considerable pedagogical significance is the fact, moreover, that
the per cent of hearing children whose vision is very poor—o.5o
normal or lower for one or both eyes—is nearly one-half greater
than in the case of deaf children. Accordingly, it is clear that
deaf children are not handicapped by visual defects, to any
greater extent than are those children not afflicted with loss
of hearing. By way of accounting for the relatively poor show-
ing of deaf children among those whose vision is normal or
nearly So, it is probable that resort must be made to some psycho-
logical explanation induced by the deaf child’s inability to react
to the test as efficiently as do hearing children. And owing to
the paucity of numbers too much weight must not be attached
to the apparently better showing of deaf children when com-
paring those whose vision is very poor. As much as can be
asserted with confidence is that it is extremely probable in the
light of the experimental data exhibited in Table III, that deaf
and hearing children, on the whole do not differ as regards vis-
ion. A summary of the comparisons just made will perhaps
show what has been said to better advantage.
24 EXPERIMIENTAL STUDIES
Whole number of children: Deaf, 353 ; hearing children, 1,436.
Number. Per cent
Vision, 1.00 (20-20) or better. * Deaf. . . . . . . . . . . . . . . . . . . . . . . . . . 225 63.7
€yêS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hearing child. . . . . . . . . . . . . . . . 972 66.9
Vision, 1.00 (20-20) or better. one; Deaf. . . . . . . . . . . . . . . . . . . . . . . . . . 264 74.8
eye at least. . . . . . . . . . . . . . . . . . . . . . Hearing child... . . . . . . . . . . . . . . 1153 79.0
Vision, 0.67 (20–30) or better. Both | Deaf, . . . . . . . . . . . . . . . . . . . . . . . . . 282 79.9
eyes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hearing child... . . . . . . . . . . . . . . 1123 78.2
Vision, 0.67 (20–30) or better. One } Deaf. . . . . . . . . . . . . . . . . . . . . . . . . . 314 88.9
eye at least... . . . . . . . . . . . . . . . . . . . . Hearing child... . . . . . . . . . . . . . . 1287 89.6
Vision, 0.50 (20–40) or less. Both J Deaf. . . . . . . . . . . . . . . . . . . . . . . . . 33 9.3
€yêS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ! Hearing child... . . . . . . . . . . . . . . 188 13.1
In the foregoing statements of results and comparisons
nothing has been said as to what constitutes defective vision.
Of course it is well understood that defective vision from the
educator's standpoint is quite a different consideration from
visual defects as an oculist understands the matter. For in-
stance, a child may have normal vision (20/20) in one eye, and
the other may be only two-thirds, two-fourths, two-fifths, two-
sevenths or even less in visual acuity. It will readily be granted
even by oculists that if a child possesses sufficiently acute vision
to be able to carry on his school work well he must be placed in
a different category from those whose vision seriously impede
their school labors. Very unfortunately the minimum degree of
visual acuity that must be possessed to insure against eye strains,
inefficient book- and black-board work, and certain physical ills
which attend the functioning of weak visual organs, has not yet
been determined. Indeed it is improbable that any hard and
fast line can ever be set to mark off the functionally efficient
from the inefficient eyes, and particularly not in terms of visual
acuity alone. One frequently finds instances where the dioptric
defect is seemingly grave, and yet the individual appears to see
well and experiences no ill effects from the use of his eyes,
and on the contrary a very slight irregularity in the organ of
vision itself is frequently attended by very serious pains and
strains. In the latter the trouble is induced by bodily or nervous
depletion, primarily, and only secondarily is it to be attributed
to irregularity in the structure of the dioptric media.
*
PHYSICAL CONDITION.
Besides the foregoing data on the comparative sensitivity of
the sight and hearing of deaf children, and their acquired power
of speech after definite periods of School instruction, it is of im-
portance to gain some definite idea of their general physical con-
dition.
Here again it is to be observed that so-called practical obser-
vations and verbal descriptions of differences between this group
of children and normal children have always led to exaggerated
accounts and unwise statements regarding the deaf, sometimes
to their advantage, but more often to their disparagement. There-
fore the more positive and precise are the statements and the
greater variety of aspects of the physical make-up investigated,
the greater is the hope of our understanding the exact condi-
tions that must be encountered in attempting to educate these
children into citizenship. It is on this account highly desirable
to present certain quantitative statements of the physical status
and deficiencies of deaf children as are evidenced in the two
more or less, closely related aspects of physical growth, viz.,
size or bulk and movement or control.
In pursuance of this end, in the following tables are given
the comparative stature, height-sitting, weight, lung capacity,
maximum length and breadth of head, strength of hand-grip
and voluntary motor ability, distributed according to age and
sex throughout. (The greater number of cases (293) recorded
in some of these tables is brought about by the fact that they in-
clude measurements other than these made during the period of
this special investigation.)
STATURE.
The stature records represent the net heights expressed in
millimeters. (See Table IV.)
It will be seen that deaf boys are not so tall on the average
as normal hearing boys at any age with the exception of those
at the age of Io years, at which time a slight difference is in
favor of the deaf boys. This exception may be accounted for by
26 EXPERIMENTAL STUDIES
a class of boys who had been receiving instruction and unusual
physical training since their kindergarten days and who pos-
sessed especially favorable home surroundings:
The deaf girls before the age of Io years are noticeably
shorter than hearing girls and the differences are greater than
the inferiority of deaf boys for their corresponding age—norms;
but after this age the deaf girls are almost uniformly taller than
their hearing companions. To be sure the numbers are small
and the cases (75) of those years of apparent superiority may
be exceptional in this respect, but the fact is indicative at least
that for the deaf girls the disabilities which they experience in
hearing or the causes of their affliction have not, during this span
of years, impaired their growth as measured by their stature.
The height-sitting measurements show (Table V) that deaf
boys are uniformly inferior throughout the years represented.
The girls on the other hand are inferior up to the age of II
years; at the ages II, I2 and I3 they are taller sitting; at I4,
I5 and 16 years they are again inferior, and thereafter the four
cases show excess over the hearing girls.
Taking the deaf children as a whole and comparing them
with hearing children with regard to stature it is found that only
Seventy-seven out of one hundred and seventy-seven, or 43.5
per cent, of deaf boys are equal to or above the average stature
of hearing boys for equal age as against eighty-eight that would
be found with the same normal hearing boys, and in height-sit-
ting only sixty out of one hundred and sixty-seven boys, or
35.9 per cent, are equal to or above the average of normal hear-
ing boys, instead of a possible eighty-three or eighty-four out of
one hundred and sixty-seven in a normal group. Again we find
only fifty-two out of one hundred and twelve deaf girls, or 46.4
per cent who are equal to or above the average statures for the
normal hearing girls of their respective ages, and in height-sit-
ting only forty-three out one hundred and ten, or 39. I per cent,
are equal to or above the average of hearing girls for the same
ages represented. Both deaf boys and girls, consequently, it is
learned, are not quite so tall as are hearing children of corre-
sponding ages, and the deaf of both sexes have shorter bodies.
than do their hearing companions.
• *-* , as * : º TABLE IV.
STATURE.
Boys Girls
Age Deaf children, Hearing children, Deaf children, Hearing children,
No. of average height. A. D. average height. No. of average A. D. average
Yrs. Mos. C2S6S. Millimeters Millimeters C3 SCS height. height.
Millimeters Millimeters
6. . . .6 10 1123.2 28.0 1132.5 9 1097.3 35.4 1125.1
7.... 6 23 1178.2 44.2 1183.9 15 1163.4 45.7 1182.2
8. . . .6 23 1185.4 55.6 1234.8 14 1201.1 26.7 1227.5
9.... 6 18 1287.1 51.2 1288.0 7 1250.7 31.7 1277.4
10.... 6 20 1335.4 55.0 1330.3 12 1326.2 55.3 1324.1
11.... 6 12 1357.0 66.3 1371.9 7 1403.0 63. 1 1383.0
12, ... 6 14 1370.2 57.5 1418.9 8 1484.3 51.8 1443.2
13. . . .6 15 1465.9 69.6 1490.9 11 1541.1 72.1 1510.4
14. ... 6 12 1528.1 69. 1 1547.4 7 1501.7 84.5 1562.4
15. . . .6 13 1505.5 68.1 1614.1 11 1577.1 61.9 1574.2
16.... 6 11 1655.9 75.7 1666.5 5 1637.0 74.8 1591.8
17. . . . 6 4 1637.3 32.3 1690.4 6 1606.0 32.3 1593.4
18. . . .6 2 1633.0 69.0 1734.1 : ] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ." . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
S

28 EXPERIMIENTAL STUDIES
WEIGHT.
With reference to weight (See Table VI) it may be said
that the deaf boys on the average are almost uniformly lighter
than the hearing boys, and although there are exceptions to this
at ages 7, 15 and 18, the numbers and the average deviations at
these ages make the data non-significant. In the case of the
girls there is greater irregularity in the data. This does not
become evident, however, until after the age of Io years. The
girls are, still, at no age, where the numbers are at all significant
as inferior to the norms for their hearing sisters as are the boys.
Again comparing the deaf children as a group with hearing
children, it is found that in weight, there are only forty out of
eighty-five boys, or 47 per cent, who are equal to, or above, the
averages for hearing boys for the same ages, and with girls we
find thirty-two out of a total of fifty-three girls of all ages, or
60.4 per cent, who are equal to or above the average of normal
girls for their ages. While deaf boys are, on the whole, there-
fore, slightly lighter than hearing boys, deaf girls are consider-
ably heavier on the average than are hearing girls of compar-
able ages.
HEAD MEASUREMENTS.*
In Table VII are recorded the head measurements of the
deaf children, boys and girls by ages; the average maximum
length and breadth of head of deaf children with the average
deviation for each age group placed side by side with the corre-
sponding figures for hearing boys and girls. (Note—See p 88.)
It will readily be seen that almost uniformly the deaf boys
have shorter heads than the hearing, and that in breadth of
head the deaf boys are almost as uniformly wider than the aver-
age of our norms from hearing children. Deaf girls show the
same tendencies in head measurements as the deaf boys. The
average maximum length of head of the deaf girls is less, while
the average greatest breadth is greater, although indeed there
are exceptions in breadth at ages 9, II, I6 and I7.
*The Smedley cephalometer was employed to make these meas-
urements. The details and methods with reference to the head meas-
urements conform with those of our best American and German anthro-
pologists.
- TABLE V.
HEIGHT SITTING.
Boys Girls
Age Deaf children, Hearing children, Deaf children, Hearing children,
No. of average height A. D. average height No. of average height A. D. average height
CaSCS sitting. sitting. CalSeS sitting. sitting.
Yrs. Mos, Millimeters Millimeters Millimeters Millimeters
5.... 6 2 584.0 2.0 | . . . . . . . . . . . . . . . . . . . . 2 593.0 5.0 | . . . . . . . . . . . . . . . . . . . .
6.... 6 11 622.8 13.8 635.4 10 600.8 33.1 629.0
7.... 6 20 642.1 22.9 657.8 14 647. 9 17.6 652.5
8.... 6 23 668.6 19.3 677.2 12 658.1 14.3 674.3
9.... 6 16 697.3 25.3 698.5 11 681.0 36.5 692.1
10.... 6 18 710.0 25.4 712.6 10 706.2 8.1 708.9
11.... 6 12 718.5 27.6 729.3 7 749.7 27.4 735.8
12.... 6 14 725.5 19.5 747.0 8 776.8 47.8 762.9
13. ... 6 15 759.3 25.9 777. 9 10 809.2 32.2 795.4
14. ... 6 11 792.3 41.4 806.4 8 804.9 33.6 824.3
15.... 6 12 797.5 30.6 836.8 11 825.8 40.5 839.9
16.... 6 10 859.0 45.8 871.7 3 829.3 21.0 850.9
17. ... 6 4 849.0 47.0 891.4 6 861.7 11.0 853.0
18. ... 6 1 914.0 | . . . . . . . . . . . . . . . . 914.6 2 865.0 23.0 857.2
19. . . .6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 855.8 31.8 | . . . . . . . . . . . . . . . . . . . .
§
3O EXPERIMIENTAL STUDIES
In addition to average lengths and breadths are given the
averages of the products of length and breadth of the head of
each child of both the deaf and the hearing children of the sev-
eral ages (Table VII). By consulting the columns of the table
which represent products it will be seen that in the case of the
boys, the deaf are uniformly inferior to the hearing children,
and this comparative status likewise obtains throughout with
the girls with the exception of the age of I2, where the nine
cases measured show a superiority on the side of the deaf.
In these measurements again let us consider the deaf as a
group and compare them with normal hearing children of com-
parable ages. In length of head only sixty-seven cases out of a
total of two hundred and seven, 32.3 per cent, are equal to or
in excess of the average hearing child for each age group. In
breadth, however, there are one hundred and twenty-four of the
whole number of two hundred and seven boys whose heads are
as broad or broader than the average—59.9 per cent.
Practically the same ratio obtains in the same measurements
with the girls. Only thirty-seven out of a total number of one
hundred and twenty-seven girls, or 29.1 per cent, are equal or
greater in length of head than the averages of our normal group
and in breadth there are eighty-seven out of the whole number
of girls, one hundred and twenty-seven, or 68.5 per cent, whose
heads are as wide or wider in greatest breadth than the average
of the normals for their ages of hearing children.f
Deaf children have, as a whole, therefore, smaller heads
than do hearing children, taking as a criterion the length, breadth
product,” and they are more brachiocephlic, broad-headed.
#These norms Of head measurementS have been taken from the
Statistics on Growth by Franz Boas, published in Report of Com-
missioner of Education, Chapter II, 1904. It is found in consulting
the records of this Department that with reference to this particular
physical measurement our cases are so largely atypical, that it is
thought unsafe to adopt them in a comparative study of this character,
and On this account recourse is had to the careful record of individual
Fmeasurements in the report of Professor Boas. The standard devia-
tions recorded in his tables are translated into the average deviation
by using the formula A. D.—,7979ö.
*It Would have been better, no doubt, to have rendered a comparison
of head Size based on the three head dimensions, employing as the
height measurement the maximum height of the head above the floor
of the auditory meati, but it was impossible for us to get satisfactory
records of the last named measurement.
TABLE VI.
WEIGHT.
Boys Girls
Deaf Children Hearing Children Deaf Children Hearing Children
Yrs *. OS No. of cases Average 1bs. A. D. No. of cases |Average 1bs. | No. of cases | Average it. A. D. No. of cases Aºaze
6. . . . . . 6 5 46.4 2.6 227 45.6 5 42.2 2.6 204 43.8
7. . . . . . 6 Q 5.2.1 4.0 230 49.6 4 47.1 3.7 236 48.5
8. . . . . . 6 17 54.8 4.2 255 55.4 4 51.3 4.0 232 52.8
9. . . . . . 6 7 57.4 6.2 228 60.8 7 61.6 4.6 221 58.3
10. . . . . . 6 12 62.0 6.2 254 64.65 5 63.8 4.2 240 64.0
11 . . . . . . 6 6 65. 1 7.0 228 71.5 3 72.6 6.6 223 71.0
12. . . . . . 6 6 66.9 7.7 256 78.4 3 85.6 6.4 247 80.3
13. . . . . . 6 8 86.7 8.1 230 88.6 7 86.9 7.7 255 91.2
14. . . . . . 6 5 88.2 12.5 250 98.5 3 96.9 17.2 301 103.4
15. . . . . . 6 4 118.1 13.0 205 112.2 5 109.3 16.9 379 108.5
16. . . . . . 6 2 116.8 11.8 146 121.5 1 99.7 | . . . . . . . . . . . . . . 358 114.3
17 . . . . . . 6 2 122.1 6.6 92 130.3 4. 129.1 8.1 251 116.2
18. . . . . . 6 2 146.1 4.6 40 138.3 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
19. . . . . . 6 2 128.9 5.7 23 141.6 1. 97.7 | . . . . . . . . . . . . . . 48 120.0
20. . . . . . 6 1 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158.2 1. 107.4 | . . . . . . . . . . . . . . 22 118.9
21. . . . . . 6 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1. 107.6 | . . . . . . . . . . . . . . 4 120.5
24. . . . . . 6 : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 116.6 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
º
32 EXPERIMENTAL STUDIES
LUNG CAPACITY.
The measurement of the lung capacity was taken by means
of the ordinary wet spirometer (Narragansett) and simply in-
dicates the greatest amount of air that can be expelled from the
lungs after a forced inspiration. This is after everything is
considered, perhaps also the best test of the amount of air that
is available for use. It may not give a direct index of the actual
or possible size of the lungs, but it affords in a way a convenient,
safe and valuable criterion of the degree of activity to which
the vocal apparatus has been subjected, or is capable of exercis-
ing at the time the test is made, as well as the extent of the
child’s general physical activity. It is on this account quite
natural that we should find that the deaf children are markedly
inferior in lung capacity to normal hearing children, and this
palpable inferiority, even in the case of those deaf children who
were given special physical and speech training, gives us an in-
dication of the immense amount of physical exercise other than
speech that normal hearing children naturally indulge in and
from which the deaf are barred by reason of their sensory handi-
caps. The intimate relation which exists between middle ear
infirmities, high and narrow bone-palate formation with all the
accompaniments and causes of obstructed breathing and dimin-
ished lung capacity has doubtless been observed by every careful
investigator of normal children with merely defective hearing.
It has likewise been pretty well recognized that the amount
of usable air in the lungs of normal adults varies, within
limits, with the degree of general physical activity. But besides
suffering the consequences of inertness during early years, the
deaf children do not give their lungs anything like the same de-
gree of exercise that normal hearing children indulge in, since
indeed they vocalize so little, and hence the cumulative effects
of this double handicap becomes palpable and hard to overcome
even with persistent exercise. In no other particular are the
deaf children so uniformly or markedly inferior to the hearing
normal children as in lung capacity. This is seen clearly by
reference to Table VIII.
The deaf boys are inferior at every age. This inferiority, to
be sure, is not so pronounced at ages II and I2 years, or at
$3
TABLE VII.
HiAD MEASUREMENTS.–BOYS.
- - s
Length-Deafs Length-Hearings” Breadth-Deafs Breadth-Hearings | Average pro- | Average pro-
Age No. of -------- I - --- *ś ... .
Ca,SeS and breadth- an rea. wº
IIllin, A. D. IIll Il A. D. In 111, A. D. IIll Il. A. D. Deaf Hearing
6 Q 180.4 7.1 178.2 5.3 143.2 4.4 140.7 4.1 25768 25866
7 28 172.5 7.1 179.6 5.1 142.1 4.8 142.1 3.7 24776 25627
8 26 176.9 8.8 180.1 4.5 144.3 3.9 143.6 3.8 25562 26325
9 15 175.5 7.1 181.2 5.0 144.4 4.1 144.0 3.7 25119 26649
10 22 181.7 6.2 181.7 4.4 146.8 9.1 144.5 3.6 26750 26912
11 17 180.5 6.2 183.4 4.8 146.0 4.4 144.6 4.0 26364 26707
12 18 177.5 7.8 183.3 4.8 147.1 5.3 145.6 4.5 26098 27242
13 18 181.5 7.2 185.2 5.1 146.7 4.0 146.8 3.8 26643 27186
14 13 182.7 5.5 187.2 5.1 151.0 4.1 146.9 3.8 27253 273.71
15 17 181.9 7.0 188.3 4.9 148.5 5.3 148.1 3.7 27025 27832
16 11 184.6 5.2 190.8 6.1 147.6 5.6 149.2 3.8 27275 285.15
17 6 185.3 4.6 191.6 4.8 148.0 6.3 149.5 3.9 27456 2877 7
18 4 185.2 6.7 | . . . . . . . . . . . . . . . . . . . . . . . . . 147.7 4.2 . . . . . . . . . . . . . . . . . . . . . . . . . . 27388 29088
FIEAD MEASUREMENTS-GIIRLS.
Length-Deafs Length-Hearings Breadth-Deafs Breadth-Hearings Average pro- | Average pro-
Age No. of duct of length duct of length
CaSCS IIT IIle A. D. IIllſle A. D. Iſidºl, A. D. IILLIle A. D. and breadth- and breadth-
Deaf Hearing
6 11 165.8 6.0 173. 1 3.7 140.1 3.1 138.0 2.8 23750 23984
7 12 169.1 4.1 174.7 4.8 142.5 4.6 139.1 3.3 23986 24571
8 15 172.7 4.4 175.0 4.7 141.6 2.7 140.3 3.4 24533 24639
9 11 170.0 3.8 176.3 5.0 135.9 3.7 140.2 3.8 23573 24782
10 13 174.1 6.7 177.8 4.7 144.9 3.4 142.1 3.6 25256 25429
11 11 173.6 5.1 178.2 4.3 141.4 4.8 142.1 3.9 24587 25542
12 9 180.5 6.2 180.0 4.3 147.0 2.6 143.2 3.7 26574 25564
13 12 179.0 5.9 181.7 5.4 146.1 5.5 144.0 3.9 26167 26386
14 7 182.0 5.1 182.5 5.1 144.5 4.7 144.0 4.2 26339 26431
15 13 179.6 6.1 184.3 4.1 146.0 3.8 145.4 3.6 26247 26370
l6 6 175.8 4.1 183.7 4.5 143.0 5.6 144.6 3.9 25172 26206
17 7 179.0 6 184.8 4.4 143. 4.0 145.2 3.4 25709 26791
*Among the hearing children the figures represent the average measurements of approximately 100 children of each sex for
each age group.



34 EXPERIMENTAL STUDIES
the particular epoch in their lives at which we notice that some
of the other measusements showed an equality or even superior-
ity to the norms for hearing children. The same inferiority is
apparent in the case of the deaf girls, and here again the great-
est inferiority is shown at those years, Io, II and I2 years, at
which we previously saw a lack of uniformity.
Here again it should be noted that because of the relatively
small number of children examined at each age it is probably
a safer criterion to take the total number of deaf children whose
lung capacity is equal to or above the average for hearing child-
ren of the same age. In counting over the cases with this object
in mind we find among the one hundred and forty-seven deaf
boys, of all ages examined, that only eighteen, or I2.2 per cent,
are equal to or above the average for hearing boys, and that in
the case of the deaf girls thirty-two out of a total of ninety-five
of all ages, or 33.9 per cent, are equal to or above the average
for hearing girls, instead of 50 per cent, which figure would
indicate them as normal.
It is interesting to note the position of deaf children with
reference to lung capacity in the per centile group of hearing
children.”
These are shown in Table IX, in which is indicated the per
centile group of hearing children into which the average of the
records of the deaf of each age fall. In a parallel column is
given also the average for each age, of the ratios which the in-
dividual lung capacity records of deaf children make with the
average lung capacity of hearing children of the same age. Thus
it is seen that the average lung capacity of deaf boys, and girls
as well, of the mean age of six and one-half years, falls in the
*For an explanation of these percentile groupings, see Report of
the Child Study Department, Public Schools, Chicago, 1901, p. 13. In
brief, the method of procedure was as follows: the four or five hun-
dred records secured for the children at each age were distributed
according to rank. The minimum measurement gives the zero per-
centile for the whole group. To determine the ten percentile, ten per
cent of the number of cards is removed, beginning with the minimal
record, and the highest measurement On the card SO removed is re-
Corded as the maximal limit of the ten percentile group. A similar
placing and selecting of the next highest ten per cent of records with
their minimal and maximal limits gives us the twenty percentile group,
and so on, for the others.
TABLE VIII.
LUNG CAPACITY.
Boys Girls
Deaf Children Hearing Children Deaf Children Hearing Children
. Age No. of Average A. D No. of Average No. of A verage A. D. No. of Average
Yrs. Mos CalSeS Cll, CII1S, Ca. SeS Cºl. CITIS. C3 SeS Cl1, CIIlS. tº sº-ºº º CalSeS Cll, CII1S,
6. . . . . . 6 9 833 181 227 1098 8 631 114 204 1008
7. . . . . . 6 17 1003 174 230 1240 6 800 200 236 1121
8. . . . . . 6 21 1164 172 255 1388 9 983 148 232 1215
9. . . . . . 6 11 1282 169 228 1549 10 1283 168 221 1360
10. . . . . . 6 19 1466 146 254 1659 8 1394 84 240 1456
11 . . . . . . 6 12 1604 195 228 1799 7 1571 153 223 1587
12. . . . . . 6 12 1704 138 256 1956 9 1706 349 247 1729
13. . . . . . 6 17 1868 186 230 2246 11 1828 285 255 1924
14. . . . . . 6 7 2171 367 250 2527 5 1990 352 301 2117
15. . . . . . 6 9 2239 290 205 2858 9 2106 341 379 2225
16 . . . . . . 6 6 2817 277 146 3363 5 2150 380 354 2306
17. . . . . . 6 2 2250 755 92 3570 6 2.192 325 251 2304
18. . . . . . 6 3 3067 843 40 3700 3 2133 310 137 2351
19. . . . . . 6 2 3200 150 23 3872 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 2441
20. . . . . . 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1. 2300 | . . . . . . . . . . . . 22
21. . . . . . 6 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2150 | . . . . . . . . . . . . 4 2250
• * * * * ,
* * * * *
* * * * * *
* * * * , ,
|
§


36 EXPERIMIENTAL STUDIES
*
º
;
:
:
;
TABLE IX.
LUNG CAPACITY.
Boys Girls
Age Percentile Group | Average of the Percantile Group Average of the
e of Normals in ratios of of Normals in ratios of
Yrs. Mos. which deaf deaf children to which deaf deaf children to
children fall normal hearing children fall normal hearing
5....6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0–10 74
6. ... 6 0–10 .81 0–10 62
7.... 6 10–20 .82 0–10 77
8.... 6 10–20 .83 20–30 83
9.... 6 90 10–20 82
10.... 6 20–30 88 40–50 96
11.... 6 20–30 91 60–70 1.03
12.... 6 10–20 .85 10–20 85
13. ... 6 10–20 .81 20-30 88
14. ... 6 10–20 .77 10–20 84
15.... 6 10–20 .75 40 96
16.... 6 10–20 .79 40–50 98
17. ... 6 Be! ". f .63 40–50 98
elow limits o
18. ... 6 normals -48 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
19. . . .6 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30–40 95
ten per centile group of hearing boys and girls of that age, and
on the average, deaf boys have a lung capacity .81 as large as
hearing boys, and deaf girls .74 as large as hearing girls, at
this age.
The table presents the data so clearly that further comment
is unnecessary. The striking inferiority of deaf children of both
sexes at all ages, almost uniformly, stands out in this table even
more convincingly than in Table VIII.
STRENGTH OF GRIP.
To determine to what degree the strength of the grip of
deaf children is inferior or superior to normal children of the
same age and school conditions, an adjustable grip dynamometer
was used, which registers the strength of grip in kilos (I kilo=
2.2 lbs.). The gross results of these tests are given in Table X.
The ages, number of pupils of each age tested, grip of
right and left hand are given in parallel columns for boys
and girls respectively, and the norms of the grip of normal
children (taken from Child Study Report No. 2, 1899–1900),
placed in columns adjoining for ready comparison.
By consulting Table X we find that the deaf boys are slight-
ly superior in right hand at ages 7, 8, 9 and II. After the age
of 12 years they are uniformly inferior, and this inferiority in-
creases with age. The strength of left hand is superior with:
DEAF CHILDREN
37
TABLE X.
STIRENGTH OF GRIP.-DEAF BOYS.
Right Hand Left Hand
Deaf Hearing Deaf Hearing
Age No. of children, children, children, children,
CalSeS average | A. D. a Verage average A. D. Average.
#Yrs. Mos. grip, grip, gT1D, g|T1 p,
kgs. kgs. kgs. kgs.
5.... 6 2 6.5 .5 ! . . . . . . . . . . . . 5.5 .5 7. 12
6. ... 6 7 9.7 1.9 9.97 8.7 1.7 9.29
7.... 6 28 12.7 2.7 11.51 11.7 2.0 10.92
8.... 6 24 15.8 2.5 13.31 14.6 2.8 12.43
9.... 6 20 16.4 2.4 15.37 15.6 3.0 14.51
10.... 6 23 19.5 2.8 17.67 17.8 2.1 16.66
11.... 6 17 21.7 3.5 20.03 19.5 2.4 18.80
12.... 6 18 21.7 2.8 22.45 20.7 3.0 20.62
13. ... 6 18 23.4 3.0 26.43 21.1 2.2 24.40
14. ... 6 14 28.9 8.1 30.40 28.5 6.5 28.40
15.... 6 14 28.1 4.9 36.38 26.3 6.3 33.73
16.... 6 11 38.6 7.2 42.35 37.2 6.7 39.40
17. ... 6 6 37.7 2.3 47.14 37.4 1.6 42.87
18.... 6 4. 35.5 7.0 51.43 37.5 10.0 47. 16
19. . . . 6 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . sº
20: . . .6 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
STRENGTH OF GRIP.--DEAF GIRLS.
Right Hand Left Hand
Deaf Hearing Deaf Hearing
Age children, children, children, children,
No. Of average | A. D. average average | A. D. average
Yrs. Mos C3 SeS grip, grip, grip, grip,
kgs. kgs. kgs. kgs.
6. . . . . . 6 10 8.8 2.2 9. 12 8.10 2.10 8.49
7. . . . . . 6 7 12.9 1.9 10.65 9.80 2.50 9.99
8. . . . . . 6 14 11.1 2.3 11. 67 10. 60 2.00 10.96
9. . . . . . 6 11 12.6 1.6 13.88 12.20 1.10 12.99
10. . . . . . 6 13 15.4 1.7 15.43 14.70 2.30 14.46
il . . . . . . 6 11 16.8 3.3 17.65 15.60 3.10 16.58
12. . . . . . 6 Q 19.3 2.3 20. 19 16.70 2.70 18.97
13. . . . . . 6 12 24.2 4.2 23.49 22.90 4.58 21.80
14. . . . . . 6 10 23.7 3.5 26.10 22.40 3.12 24.03
15. . . . . . 6 14 27.5 3.8 27.91 25.40 4.07 25.80
16. . . . . . 6 5 35.2 3.4 29.50 30.10 2.80 27.31
17. . . . . . 6 7 32.0 3.1 29.63 29.00 2.85 27.55
18. . . . . . 6 1 33.0 | . . . . . . 29.87 28.00 | . . . . . . . . 27.77
; is a tº a e º ; 4. 39.0 2.0 | . . . . . . . . . . . . 32.25 5.25 | . . . . . . . . . . . -


the deaf boys at ages 7, Io, II, I2 and I4 years and inferior at
ages 6, 8, 9, 12, 13, 15, 16, 17 and 18.
The deaf girls are weaker in right hand grip than the norms
for hearing girls at ages 6, 8, 9, Io, II, 12, 14, 15 and slightly
stronger at ages 7, 13, 16, 17 and 18. Practically the same com-
parative status obtains in grip of left hand of these deaf girls.
Again because the number of cases of the deaf is so small,
a comparative estimate of the children as a whole may better be
38 EXPERIMIENTAL STUDIES
made from the number of children of the group who are equal to
or superior to the average of our normal children in this test of
strength. In actual numbers it is found that ninety boys out of
two hundred and four, or 44.1 per cent, are equal to or Superior
to the averages for hearing children. With the left hand, as a
group, the deaf boys stand higher than with the right hand, in-
asmuch as one hundred out of two hundred and four, or 49.7
per cent, are equal or superior to the average of children of the
ages included in the norms.
In the case of the deaf girls there are fifty-five both left and
right hand out of the total number of one hundred and twenty-
four, or 44.4 per cent, who stand equal to or Superior to the
norms of hearing children for the ages represented. It appears,
therefore, that the deaf boys as a group more nearly approach
the norms of their hearing companions than the girls with the
left hand, while the advantage is slightly in the favor of deaf
girls as a group in respect to the right hand.
GRIP INDEX.
The observation has quite frequently been noted * that left-
handedness is found more frequently among deaf children than
among the hearing. Various reasons have been assigned for
this peculiarity, although all agree, however, in supposing that
there is some intimate connection between speech and this dif-
ferentiation in hand power or selectiveness in manipulation.
In Report No. 2 (1900) of this Department, the data with
reference to changes in growth of hand strength of normal
children were presented. Moreover, it will be remembered that
in Prof. J. Mark Baldwin's studies of his two children ++ there
was an account of a noticeable preference for one hand Over
another in grasping for attractive objects which made its initial
appearance about the time of speech beginnings. This apparent
correlation of the two modes of expression at the time of their
origin seems to be again in evidence at the time of the great
**Mental Development in the Child and the Race, 1896, chap. I.
*Hartmann, Ueber TaubStumme, Deutsch med. Wochenschr, III,
1877.
Deaf-Mutism—(trans. Cassell), 1880. J. Kerr Love; Deaf-
Mutism, Chap. I, Glasgow, 1896. St. Hilaire: La Surdi-Mutite, p. 251,
Paris, 1900.
DEAF CHILDREN 39
transformations of life. An instance of this occurs during the
pubertal epoch. In the reports of this department attention was
called to the fact that the greatest difference between the
strength of the hands occurred at early adolescence contempo-
raneously with the greatest changes of voice. Another group of
facts somewhat akin in import relates to speech defects. It was
found in our work that by far the greatest number of minor
speech defects was discovered among children who were pro-
nouncedly left-handed or who acquired ambidexterity by reason
of the teacher’s persistence and the parents’ training. This
whole line of reasoning may be merely a matter of coincidence.
It seems much more reasonable to suggest that all cases of minor
speech defects correlate directly with inferior intelligence, as
TABLE XI.
MANUAL INDEX.*
GRIP.
Boys Girls
Deaf Hearing Deaf Hearing
A ge
Yrs. Mos. No. Of Index | No. of | Index No. of Index No. of | Index
cases per cent cases | per cent CaseS per Cent CaSeS per Cent
6. ... 6 7 88.8 | . . . . . . . . . . . . . . . . . . 10 89.6 | . . . . . . . . . . . . . . . . . . .
7.... 6 28 90.0 8 Q3.1 7 85.0 9 90.0
8. ... 6 24 87.0 29 92.0 14 93.0 28 92.9
9. ... 6 19 86.0 44 93.1 12 91.0 30 91.5
10.... 6 23 89.0 42 93.04 13 92.0 41 91.7
11. ... 6 16 94.0 44 95.4 11 94.0 45 92.1
12. ... 6 18 92.0 40 91.6 9 86.0 47 92.4
13. ... 6 18 91.0 48 91.1 12 95.0 45 93.6
14. ... 6 14 94.0 36 91.8 8 92.6 64 93.1
15.... 6 14 93.0 31 92.5 14 91.0 47 91.7
16.... 6 11 93.0 20 90.9 6 93.16 39 90.6
17. ... 6 5 94.2 90 91.8 7 90.85 51 89.9
18. ... 6 4 93.2 37 89.4 4. 83.0 75 89.9

*NOTE.-The measure of the Index is in each case, the per cent which the
weaker hand is of the stronger. The degree of right- or left-handedness is
not therefore indicated.
indeed our work with subnormal pupils would seem to indicate,
and that ambidexterity is one of the marks of inferior mental-
ity instead of the converse, as further work with reform school
boys gave evidence of. (See General Reports II and III). This
feature of the whole matter is held in reserve for another series
of studies.
It must not be forgotten, however, that this matter of the
4O EXPERIMENTAL STUDIES
number of deaf children who are left-handed is a relatively sec-
Ondary problem in comparison with the larger aspects of growth
in hand strength which center about the differences in hand
power between the right and left hands of deaf children through-
out the years of growth.
This growth in specialization is indicated in Table XI, in
terms of manual index. The measure of the manual index is in
each instance the per cent which the weaker hand is of the
Stronger, and for convenient comparison the index of normal
hearing children is placed in adjoining columns, both for boys
and girls.
There seems to be greater difference—that is, the manual in-
dex is less—between the strength of grip of the hands of deaf
boys as compared with hearing boys at the ages 7, 8, 9, Io and
II years. Beginning with the age of I2 years and from 12 to
18 years, both inclusive, there is less difference in the strength
of the hands of deaf boys as compared with their hearing mates
of corresponding ages. In comparing the younger deaf boys
with those older in years it is found that, in general, the differ-
ence between the strength of the hands tends to diminish, that
is, whereas, in the early years the manual index is less than
ninety, it goes up to ninety-three or ninety-four in the older
years. As the deaf boys increase in age there is less and less
difference between the strength of their hands, less specialization
or selectiveness in manual power. This is the direct opposite of
what we find among hearing boys, among whom we find that the
strength of hands is more equal in the early years, and that the
difference between the hands increases perceptibly as they grow
older.” This may be only another indication that deaf boys are
later in maturing than hearing boys, or that the lack of activity
of all sorts and especially of constructive manipulation of ma-
terials is So great an environmental handicap as to practically
make the deaf boys a species by themselves. There is by no
means so great uniformity found in the differences of hand
power of deaf girls as compared with their hearing companions
of equal ages. There is less difference between the strength of
*Compare Binet. Quotation from Dr. St. Hilaire, “that grip of left
Jhand differs less from light hand than normals.” Also, Kilian.
DEAF CHILDREN 4 I
the hand of deaf girls at ages 8, Io, II, 13, 16 and 17 years;
and greater difference between the hands of deaf girls than in
the case of hearing girls at ages 7, 9, 12, 14, 15 and 18 years
respectively. The general tendency, however, so far as this can
be read from the data at hand, seems to show that up to the age
of 12 years there is less difference between the strength of hands
of deaf girls than hearing girls of equal ages—the direct oppo-
site of the relation that was found to obtain in the case of
deaf boys.
In comparing the younger deaf girls with those of older
years we find that the differences between the hands increase as
they grow older, the opposite of what we found prevailing
among deaf boys, and more in line with the trend of develop-
ment of normal hearing girls. Again this may be largely due
to the fact that the difference in activity which is found between
deaf and hearing girls is not so great as the difference between
deaf and hearing boys.
To summarize, the nature of the data is such as to make it
unwarrantable to assert that any differences exist in relative
strength of the two hands of deaf girls as compared with their
hearing sisters, but with reference to deaf boys the data seem to
indicate that for younger years, during pre-adolescence, more
differentiation in the strength of the two hands, respectively, ob-
tains than among the hearing, and for the adolescent years, less
differentiation prevails than among children with normal hear-
ing—that is, the deaf are more ambidexterous.
MOTOR ABILITY.
In examining the voluntary output of energy one should take
into account not only the gross and spasmodic total result of
effort usually called strength and represented in one instance as
hand-grip (Table X), but also the factor of the quickness or
speed of voluntary movement. This factor of voluntary motor
ability is recorded herein as simple tapping-time, and in our tests
registers the number of taps that can be made with an electric
tapper during thirty seconds. The two most important elements
in a test, namely, precision of movement and constancy in effort
and execution unfortunately we shall have to ignore entirely,
and hence there is presented only the total number of taps made
during thirty seconds.
42
EXPERIMENTAL STUDIES
TABLE XII.
MOTOR ABILITY-DEAF BOYS.
Right Hand Left Hand
Deaf Hearing Deaf Hearing
Age No. of children, children, children, children,
cases average no. A. D. average no. average no. A. D. average no.
Yrs. Mos. of taps, of taps, of taps, of taps,
30 secs. 30 Secs. 30 secs. 30 Secs.
5.... 6 2 76.1 15.0 l. . . . . . . . . . . . . . 72.0 12.0 | . . . . . . . . . . . . . .
6. ... 6 7 117.8 19.5 ! . . . . . . . . . . . . . . 100.5 2.6 | . . . . . . . . . . . . . .
7.... 6 20 120.1 13.5 ! . . . . . . . . . . . . . . 97.7 13.8 | . . . . . . . . . . . . . .
8.... 6 22 129.2 18.6 147 105.8 22.6 117
9.... 6 22 137.9 10.8 151 115.0 12.3 127
10.... 6 22 • 138.0 19.5 161 114.6 19.0 132
11.... 6 17 146.8 16.1 169 124.1 16.1 141
12.... 6 18 163.3 15.5 170 141.2 14.4 145
13. ... 6 17 165.3 16.9 184 145.0 20.0 156
14. ... 6 14 174.0 21.5 184 145.4 18.7 155
15.... 6 17 176.4 26.4 191 152.8 16.6 169
16.... 6 12 182.0 21.5 196 159.5 20.1 170
17. ... 6 7 162.4 9.9 196 146.3 18.6 174
18. ... 6 4 164.5 12.5 197 150.6 25.7 183
19. . . . 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
20. . . .6 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MOTOR ABILITY-DEAF GIRLS.
Right hand Left hand
Deaf Hearing Deaf Hearing
A ge No. of childen, children, children, children,
cases average no. A. D. average no. average no. A. D. average no.
Yrs. Mos. of taps, of taps of taps, of taps,
30 Secs. 30 Secs. 30 secs. 30 Secs.
5.... 6 1 115.0 | . . . . . . . . . . . . . . . . . . . . . . 105.0 l. . . . . . . . . . . . . . . . . . . . . . .
6. ... 6 8 112.9 11.1 ! . . . . . . . . . . . . . . 95.1 26.0 [ . . . . . . . . . . . . . .
7.... 6 13 109.9 14.5 ! . . . . . . . . . . . . . . 103.7 21.3 | . . . . . . . . . . . . . .
8. . . . 6 14 122.5 12.2 146 93.8 17.0 117
9.... 6 10 134.9 14.5 149 116.5 13.8 118
10.... 6 13 141.5 17.2 157 128.2 12.1 129
11.... 6 10 148.2 22.4 169 132.2 13.0 139
12.... 6 9 153.7 20.6 169 131.4 20.2 140
13. ... 6 12 156.9 18.1 178 137.1 26.9 153
14. ... 6 7 157.7 21.1 181 133.3 14.0 157
15. ... 6 12 174.0 24.1 181 158.7 21.0 159
16.... 6 6 177.1 12.8 188 161.1 10.5 167
17. ... 6 7 175.7 14.9 184 163.4 11.9 162
18. ... 6 1 178.0 | . . . . . . . . 193 159.0 [ . . . . . . . . 169
19.... 6 3 188.0 18.0 [ . . . . . . . . . . . . . . 171.0 9.3 | . . . . . . . . . . . . . .
20.... 6 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .''. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


In Table XII are given in parallel columns the following:
(a) The number of children tested at each age.
(b) The average number of taps made in thirty seconds by
the children.
(c) The average deviation of the records from the average.
For ready comparison the averages for normal children for cor-
responding ages are placed beside those of the deaf. The rec-
ords are given for both boys and girls for the right and left
hands.
DEAF CHILDREN 43
By going over this table somewhat in detail one sees that
the deaf boys are with the right hand notably and uniformly
slower than normal hearing boys, and that although not so quick
at any age with the left hand, they are not in this case so in-
ferior, and at the age of twelve years almost equal to the hear-
ing boys. Moreover, this relative slowness seems to increase as
they grow older.
In the case of the girls we find that they too are much
slower at all ages with the right hand, and with the left, though
slower than hearing girls, they are at no age as much slower
relatively as with the right hand. Indeed, at the ages fifteen
to seventeen, they are almost equal in quickness to hearing
girls with the left hand, and at the age of seventeen years they
are actually quicker on the average. Moreover, the inferiority
of the girls, unlike that of the boys, appears to decrease with age,
and this may be only another indication of the increased degree
of general physical activity in which they come to indulge, as
well as of other environmental factors.
Again on account of the paucity of numbers at each age it
is advantageous to take the deaf boys and girls as a group and
compare them in quickness directly with the hearing boys and
girls for the corresponding ages represented in each deaf group.
It is thus found that of all deaf boys examined, only forty-one
out of one hundred and seventy-two, or 23.8 per cent, are as
fast or faster than the averages for hearing boys of their ages
with right or left hand, and that only twenty-nine of a total of
one hundred and one, 23.8 per cent, deaf girls are, with the
right hand, equal to or above the average for normal hearing
girls of corresponding ages, while only thirty-four out of ninety-
nine cases, 37.3 per cent, recorded for quickness of left hand,
equal or surpass the averages of hearing girls for the same ages.
The relative standing of the deaf, all in all, when compared
with hearing children in the cases of both boys and girls, is
therefore found to be, even less favorable, when rapidity of
movement is involved, than was found in the measurements of
stature and weight, and only slightly better than the relative
standing of the deaf in lung capacity.
The facts are diagramatically exemplified in the accompany-
44 EXPERI MENTAL STUDIES
ing figure, which indicates the positions occupied on a per centile
scale drawn from a large number of hearing children of each
age, the average standing of deaf boys and girls of correspond-
ing ages. From this it is seen for example, that the average
standing of seven year old deaf girls is lower than the average of
the lowest Io per cent of the records selected from the
performances of hearing girls. In one instance, only, I2 year
old deaf girls, does their average tapping rate exceed the aver-
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THE HORIZONTAL NUMERALS REPRESENT THE AGES OF THE RESPECTIVE GROUPS–
THE PERCENTS ON THE WERTICAL LINE SHOW THE RATINGS OF THE DEAF BOYS,
AND GIRLS FOR THE DIFFERENT YEARS.
age of hearing girls, and in the averages for three age groups
only among boys do their performances equal the average of
hearing children.
Further, in the tests of motor ability as with the hand-
strength there is an advantage and interest in giving the manual
index. This index of manual quickness (See Table XIII)
measures in each instance the fraction which the slower hand

DEAF CHILDREN 45
is of the faster. In comparing then the manual index, as deter-
mined by relative quickness of movement, of deaf boys with
hearing boys, it is seen that there is practically no difference
observable until after the age of eleven and one-half years.
After this age, however, the manual index is higher among the
deaf boys, showing that the difference in motor control of the
right and left hand is not so great as among hearing boys of
the same ages, or that specialization in this method of ex-
pression has not attained as high a degree among the deaf as
the hearing, that is, the deaf tend more to ambidexterity than do
ordinary hearing children.
TABLE XIII.
MANUAL INDEX.”—MOTOR ABILITY.
Boys Girls
Deaf Hearing Deaf Hearing
A ge
Yrs. Mos.' No. of No. of No. of No. of
C3 SeS Index C3 SeS Index CalSeS Index CalSeS Index
6. ... 6 6 79.3 . . . . . . . . . . . . . . . . . . . . . 8 85.5 | . . . . . . . . . . . . . . . . . . . . .
7.... 6 25 79.9 8 79.0 12 83.9 11 80.1
8.... 6 22 81. 18 33 81.4 14 79.0 8 80.32
9.... 6 21 83.7 60 82.6 10 83.6 44 79.4
10.... 6 22 81.9 47 82.3 12 86. 0 48 82.4
11.... 6 17 82.5 49 83.0 10 88.2 46 83. 1
12.... 6 18 87.1 44 82.5 9 86.1 49 80.7
13. ... 6 17 85.5 50 84.6 11 85.5 44 86.7
14. . . .6 14 83.2 40 82.08 7 85.1 68 86.1
15.... 6 16 86.1 35 86.6 11 87.2 48 86.7
16.... 6 11 91.7 21 87.1 6 91.1 40 88.0
17. ... 6 7 88.9 13 88.7 7 92.1 51 88.1
18. ... 6 3 86.2 3 93.3 1. 89.0 # 5.5
*NOTE.-The measure of the Index is in each instance the per cent which
the slower hand is of the faster.
Again in running our eye over the data in each column to
determine differences due to age among deaf boys, it will readily
be seen that in general there is not so great a difference between
the younger and the older deaf boys as is found to obtain in
the case of the younger normal hearing boys and the older hear-
ing boys.
With respect to the manual index of deaf girls it is seen that
at nearly every age there is not so great a difference in
the control of the hands as is found to prevail among the hear-
ing girls of comparable ages. This difference between the deaf
and hearing girls is very pronounced at some ages, notably at
46 EXPERIMIENTAL STUDIES
ages, seven, nine, ten, eleven, twelve, fifteen, sixteen, and seven-
teen years and not so marked or even slightly less at ages, eight,
thirteen, fourteen, and eighteen years. It appears safe to war-
rant the statement, however, that there is less pronounced dif-
ferentiation or selectiveness in motor manipulation among deaf
girls than is found in the case of their hearing sisters.
One fact stands out prominently in the tests of motor abil-
ity, notably that both deaf boys and deaf girls of I2 years and
older more nearly approach the standing of hearing children than
do those of the younger years. That is, as deaf children
increase in age, they become more nearly like normal hearing
children. There seems to be no other casual factor to which
this relative increase in efficiency with age can be attributed ex-
cept that lack of definite motor control is intimately related to
mental maturity. Since in their early years, deaf children have
had few experiences as compared with hearing children, this
increase in motor ability would be more rapid with mental train-
ing than is that of the hearing child. This suggestion of the
very close correlation between mentality and the development
of the nervous mechanism is likewise illustrated and exempli-
fied by work which has been done on primitive people. These
show that while not greatly inferior to the normal average white
people of civilization in strength for their stature, there is a
marked inferiority in their quickness of response. This differ-
ence in moving time is apparent even in the doing of things with
little or no meaning, as well as in the performance of acts that
require a more complex mental factor to initiate and control
them. It may be said that responses are the result of Stimula-
tion, and that the nervous mechanism, subject to the more
varied and greater number of sensations appreciated, other
things being equal, will respond the more rapidly. This cor-
relation suggests the very interesting psychological problem of
the inverse influence of the psychical on the efficiency of the
motor mechanism. The question of the influence of bodily more-
ments in giving rise to mental content has long been recognized.
The influence of the psychical on the physical means that an
unused mind, no matter from what caused, is accompanied by
sluggish bodily action. It suggests also, the influence which
School training of the purely mental type has in affecting an in-
crease in manual productivity.
MENTALITY.
The problem of determining the mental status of deaf chil-
dren is infinitely more complicated than that of estimating the
psychical efficiency of hearing children. This is to be attributed
in no small measure to the fact that their symbols for express-
ing themselves and making known to us the contents of their
minds are few and inadequate.
On account of the paucity of symbols, too, it becomes exceed-
ingly difficult to devise any tests which may be used with the
same degree of facility and certitude on the deaf and hearing
children alike, and thus make a quantitative statement of the
differences of mentality between a deaf and hearing child. This
does not mean, of course, that the mental condition of a deaf
child cannot be determined with a fair degree of certainty by
one who has had special training and has acquired special skill
in bringing out and interpreting responses which are indicative
of the deaf child's mental power. In testing the mentality the
aim was more specifically that of examining definite functions
rather than of evaluating proficiency in any particular line of
School training. -
Proceeding from the simplest to the more complex processes,
simple tests were given to determine the following functions
of the child:
(a) Imitative ability;
(b) Suggestibility; i. e., his ability to follow directions;
(c) Perceptive ability; i. e., the child’s efficiency or
skill in discriminating sense differences in degree and kind.
(d) Capability in reproducing immediately (at once) a con-
text which is relatively without connection with other meanings,
i. e., the immediate sense memory. (With the deaf children
the reproduction of things heard is eliminated.)
(e) Ability to think, i. e., to intelligently use such con-
cepts as cause and effect, part and whole, and the like.
With reference to the general power of thinking, it should
be stated that in speaking of such a highly complex mental activ-
48 EXPERIMENTAL STUDIES
ity as the power of forming good judgments, it is always
necessary to tell in advance the particular field in which this
activity is operative. It is a common observation that persons
may exercise good judgment in dealing with one phase of human
life, and yet show exceptionally poor judgment with another
group of facts. A man, for instance, may be sound in Science
but most eccentric and unsafe in business and religion. Hence
it is unwise to use any arbitrary tests for general comparison
of individuals or groups, who may happen to have had diverse
interests and different training. In this test of the deaf chil-
dren, an estimate was made merely of each child’s ability to
size up situations and in general to interpret and communicate
meanings.
In addition it should be noted that the simpler tests were
used for diagnostic purposes, and no effort was made to state
them in quantitative terms. The question of primary import-
ance was: Has the child a mind which is well balanced or
sane, and susceptible of training, or is he feeble-minded ?
Imitation.
To determine whether the child had sufficient mental abil-
ity to imitate, the following tests were employed: The child
was placed at a distance of four or five feet facing the experi-
menter. He was encouraged to observe attentively and execute
the same acts which the experimenter performed, such as (I)
placing the feet together, heels and toes; (2) standing erect,
with head and shoulders thrown back; (3) raising one or both
hands to a horizontal position at the side, and in front or per-
pendicularly above the shoulders; (4) with the hands extended
horizontally in front, the child spread apart his fingers, follow-
ing the experimenter, holding now one, and now two, together.
Suggestibility.
To determine the child's suggestibility, two tests were em-
ployed. In the first the child performed certain acts which he
had just seen the experimenter execute. He made three, four
or five, or any number of steps, after watching the experimenter
perform the same, or he tapped a certain number of times in
response to the same number performed by the experimenter.
This implies that an idea or image of the performance or end to
DEAF CHILDREN 49
be attained exists in the mind of the child, and that he has the
ability to work out the meaning of the image or idea in some
definite act or series of acts. There is also involved in a sug-
gestion test the concept or translation from one sense to an-
other. In order for the child to take three steps as a result of
having seen three hand movements, it is necessary that he have
definitely formed the concept of three, and this is by no means a
simple function.
In the second test for suggestibility packs of specially pre-
pared cards were used, and the child was required to sort them
in groups of their likes and unlikes. Three of such packs were
employed, each containing forty cards. On the cards of the first
series were pasted small circles of eight elementary colors. After
the cards had been thoroughly mixed the child was requested to
Sort them into piles, according to color. On the cards in the
second series were pictures of familiar objects instead of colors;
in the third simple geometrical forms. The procedure in all
three parts of the series was practically identical. How-
ever simple and elementary these tests for imitation and suggest-
ibility may seem, experience with large numbers of children in
the Child Study laboratory has shown that feeble-minded chil-
dren are unable to execute even such simple operations.
Perception.
As tests which largely involve simple perception three were
employed; one calling for sense discrimination by sight, the sec-
ond by the sense of touch and the third bringing into play the
muscular sense.
To test the first function—sense discrimination by sight—
use was made of a special form of what is customarily known
as the “A” Test. (See form of this test, pp. 50 and 51.) The
test is one which has done service in the Child Study Laboratory
of the Chicago Public Schools for a number of years, and was
invented and devised largely for diagnostic purposes. As is seen,
the test is composed of two parts. In the first, one hundred
“a’s” (18 point size) are arranged symmetrically in rows, so as
to involve the perceptive factor to a negligible degree, in mark-
ing them out, while in the second half of the test the one hund-
4 & – 3
red “a’s” are scattered promiscuously among the remaining let-
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EXPERIMENTAL STUDIES
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52 EXPERIMENTAL STUDIES
ters of the alphabet, so as to form one hundred groups of letters
of five each.
The first part of the “A” test was designed with two ob-
jects in view. By taking the time required by the child to place
a stroke with a pencil through each of the one hundred “a’s”
when he has been requested to do it as rapidly as possible, a
measure is afforded of a certain type of motor ability. But in
addition to this there is also afforded, which is more particularly
to the purpose of the test in hand, a measure of the physiological,
or motor time consumed in marking one hundred “a’s.” After
completing part one, the child was instructed to place a stroke
through the a's in the page print (see p. 51), as quickly as
possible, being sure to mark out every “a”; the instructions be-
ing uniformily as given above for deaf and hearing children
alike. A measure of the time required to perform this test was
also taken and a record made of the number of “a’s” not marked.
It is readily apparent that at least two factors enter into
the selection and marking of “a’s” as called for in this test; the
one a mental factor concerned in the several acts of discrimina-
tion in finding the “a's,” and the second, physiological, having
to do with the motor task of making the marks. To disinte-
grate these factors and arrive at a measure of the purely men-
tal time actually involved in perception, is the point of chief
moment, to make the test of value in stating quantitative differ-
ences between individuals and groups. And this is acomplished
approximately by subtracting the motor time gotten in the first
part of the test from the total time required to perform the sec-
ond part. This latter we shall call the “Perception Time” (P.
T.) in the discussions and tables.
There is one factor in connection with the “A-Test” which
makes the results awkward to handle. If every child marked out
all the “a's,” differences in perception might be stated directly
in terms of the perception time. The fact is, however, that many
children fail to find all the a's, there being sometimes as many
as forty that the child does not see and mark out. Here, con-
sequently, are two variables, which thus far there has been found
no satisfactory way of equating in terms of each other. Thus
t
TABLE XIV.
PERCEPTION TEST.-“A” TEST.
DEAIF CHILDREN
Motor time, is
average
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53



54 EXPERIMENTAL STUDIES
it is impossible to say, exactly, whether a child who has marked
out all the a's and whose perception time is 60 seconds, has bet-
ter or poorer ability, as regards this test, than the child whose
perception time is, say one-half as great—30 seconds—but who
has failed to mark out ten or fifteen of the a's. A probable de-
termination of the efficiency of children in the test, however,
was secured by calculating from the time required to mark out
the a's in each case, the estimated time that would be required
to mark out IOO a's. That is, in the event that it took I70 sec-
onds to pick out 85 per cent of the a's, it was estimated that
200 seconds would be required to pick out all the a's. No cor-
rection, however, was made for a’s overlooked in those cases
where at least 96 per cent had been marked. For the most part
the children were tested one at a time, and in no case were
there more than three children given the test together.
All the data from the “A-Test” available for statistical pre-
sentation will be found in the accompanying tables. (See Tables
XIV and XV.) The tables are sufficiently self-explanatory
to require little direction in reading off the data and their sig-
nificance. To facilitate comparisons with hearing children the
data from this group are placed in parallel columns with those
from the deaf. It is seen that there are indicated for each age:
(I) the number of children examined, (2) the average motor
time, and (3) the average perception-time (total time less motor
time), together with the average deviation of the individual rec-
ords from the mean or average of each group; also the number
of a's on the average not discerned.
Table XIV exhibits the data so as to show the relative num-
ber and per cent of deaf children of each age whose records
fall below the average or mean performance of hearing children
of corresponding ages. It is, indeed, the more telling of the two
tables, too, inasmuch as the influence of the small number of rec-
ords which make up the average of each group, and the skewing
tendencies of extreme records, loose their undue weight.
Motor Time—
We are not concerned particularly, with the question of
motor proficiency in the present instance, but it is worth while
in passing to note the comparative standing of deaf and hear-
DEAF CHILDREN 55
ing children, respectively, in motor time as measured by the
first part of this test—a form of motor-ability test. The rela-
tive motor inferiority of deaf children stands out most clearly
during the earlier years, but it is by no means lacking for any
of the ages considered in these comparative measurements, since
at no age is the average motor time for deaf children as low as
for their normal hearing companions. Table XV shows the
relative motor inefficiency of deaf children, if anything, even
more conclusively. We find that at the age of seven the rec-
ords of all deaf children are poorer than the average for hearing
children. At eight years of age, II of I6, or 69 per cent of the
deaf make poorer records; at nine years, 9 of I5, or 60 per
cent; at ten years 20 of 26, or 77 per cent, and when children
of eleven years are compared, again all rank lower than the
average for hearing children of the same age. Of the total
number of deaf children who performed this part of the test,
I48 in all, 122 or 82.4 per cent, stood lower in motor efficiency
than the averages of the records for children with normal hear-
ing of comparable ages. The numbers are too few to warrant
closer mathematical treatment, and indeed such treatment is
unnecessary in the face of the data just offered. The reasons
for this manifest motor inferiority have already been com-
mented upon, and nothing requires to be added in this place.
Perception Time—
Again looking at Table XIV, in the columns headed “Per-
ception Time,” differences between the two classes of children,
more pronounced than those shown in the ‘Motor Time,” are
observed. The time required by deaf children to pick out the
One hundred a's, on the average, ranges from almost twice that
required by hearing children at the age of seven, to more than
a third longer for the later years, fourteen and fifteen. For
none of the age groups is the average perception time of chil-
dren who have no hearing anything like as small as for chil-
dren who hear normally, though the difference between the two
groups progressively diminishes with increasing years.
Judging from this tendency of the difference in perception
time of the two classes to become less with age, it is not un-
56 } LXIPERIMENTAL STUDIES
likely that were deaf adults and those with hearing examined
and compared little difference would be discovered.
Considerable variability is exhibited by the average devia-
tions of both groups, and a much greater amount of variability
among the performances of the deaf than of hearing children.
That the differences brought out by the averages of the two
groups, however, is real, is conclusively shown by the charac-
ter of the data shown in Table XV, where the number and per
cent of deaf children whose standings are inferior to the aver-
ages of hearing children of comparable ages are given. Thus
it is seen that at the age of seven years all deaf children pos-
sess a lower standing than the average for children who hear; at
TABLE XV.
“A” TEST-PERCEPTION.
SUMMARY OF TABLE XIV.
Relative number and per cent of Deaf children whose records stand lower
than the averages for their respective ages of Hearing children.
Motor time Perception time
Number Number Number Number
Age examined lower Per cent examined Lower Per cent
7 9 9 100 7 7 100
8 16 11 69 14 12 86
9 15 9 60 15 12 80
10 26 20 77 26 23 88.4
11 15 15 100 15 11 73.2
12 Q 9 100 9 9 100
13 17 12 70 16 12 75
I4 9 78 9 : 100
15 20 18 90 20 15 75
16 12 12 100 12 8 66.7
All |
3.geS 148 122 82.4 143 118 ſ 82.5


eight, I2 of 14, or 86 per cent; at nine, I2 of I5, or 80 per
cent; at ten, 23 of 26, or 88.4 per cent of the deaf require a
longer time to pick out from among four hundred other letters
the one hundred “a’s” than the averages of their hearing com-
panions for comparable age-groups. Concerning deaf children
of all ages grouped together, we discover that 82.5 per cent,
I 18 of the whole I43 examined, have a longer perception-time
than the averages of children of the same ages not thus af-
flicted.
When the number of “a’s” not marked is taken into account
DEAF CHILDREN 57
the results are in all essential respects comparable to those
above. (See Table XIV). Deaf children not only require a
longer time on the average to discriminate between the “a’s” and
the remaining letters of the alphabet when they are intermin-
gled, as in the “A” Test, but they are also able to discriminate
less accurately than children whose ears function normally, as
is indicated by the greater number of errors, “a’s” overlooked,
—and this deficiency likewise extends to all ages. Indeed, if
we follow closely the results of the test, we are forced to say
that deaf boys and girls from twelve to fourteen show rela-
tively less discriminability than do those of the younger years.
The data regarding the A-Test are strikingly conclusive.
Deaf children, on the average, are from two to three years less
mature than hearing children of the same ages in the kind of
ability that is called for in this test. And certainly this can not
be attributed to the fact that a certain kind of skill is called
for in the test, that the lack of school training from which deaf
children suffer would fully account for. On the contrary, it is
difficult to see how ordinary school exercises would conduce to
rapid and accurate symbol discrimination, except in the gen-
eral sense of leading the child to be more keen and alert in
meeting any general and unfamiliar situation. From other tests
and measurements, as well as from intimate association and
observation, we are forced to conclude that a relative imma-
turity of from two to three years, as compared with hearing
children, extends to all phases of the mental life of the deaf,
and no doubt, too, its cause is to be found in the natural alien-
ation which the minds of these children suffer by reason of the
sensory barriers that have been set against their intermingling
in the mental and social life of the communities in which they
were born and are maturing.
Perception of Sige.
Shot Test—
The second test, which deals primarily with perception, had
for its object, as stated above, the determination of a child's
sensitivity as measured by the ability shown in discriminating
the sizes of small objects by the active exercise of the sense of
58 EXPERIMENTAL STUDIES
touch. This end was brought about by using a series of light
canvas bags containing ordinary commercial shot of the fol-
lowing sizes: Nos. BB, B, I, 2, 3, 4, 5, 6, 7, 8, 9, IO, II,
I2, dust shot.
The test had, like the foregoing test, grown out of the daily
duties and needs of the Department of Child Study, and had
been effectively used almost daily for four or five years, in the
regular series of tests and measurements given to normal and
abnormal children in the laboratory.
In conducting the test a child was first given a bag con-
taining the median-size of the series, or shot number 6, at the
same time another bag containing a size shot so large that
ordinarily little difficulty would be encountered in perceiving
the actual size-differences, after the child had rolled the shot-
bag between the forefingers and thumb.
It was found that in the case of very young deaf children
these ideas of comparison, “greater than,” “less than,” are
rather late in developing, and teachers of the manual alphabet
assert that such relational ideas are probably of all ideas the
most difficult to appreciate and express in communicable sym-
bols. With young children, especially those who had practically
no language, considerable patience and perseverance was found
necessary in order to have them get this conception of greater
and less associated with or abstracted from the objects or quali-
ties compared. Hence the necessity of using large differences
at the beginning of the test. These considerations are equally
pertinent to those perceptional tests dealing with the attempts
to determine and express differences of weights, which are con-
sidered later on. -
As soon as a degree of familiarity was gained by the child
with the test and method of procedure, bags containing shot-
sizes of smaller differences from the median-size, number 6,
were presented and compared by him each in turn with the
standard, until each size, both larger and smaller than the me-
dian, was tested and a judgment expressed on the sensed differ-
ence. In each instance great care was exercised by the exam-
iner that there be no marks of identification on the bags examined,
nor acquaintance with any particular way in presenting the bags,
DEAF CHILDREN 59
nor any other means or measure of the child’s devising or dis-
covery which could interfere with the end desired, viz.: to deter-
mine the least difference, greater or less, than the median size,
number 6 shot, that might be accurately sensed under controlled
conditions.
Whether indeed the sizes of shot used in the series are
graded uniformly or not, is a question which need not concern
us, since it would be impossible to state, even though the actual
differences between the variously numbered shot were equal,
that the qualitative results obtained in the tests have absolute
significance, e. g., that one child has twice or three times the
sensitivity to tactual perception of size that another child pos-
SČSS6S.
Below are given such measurements of the shot in diame-
ters, in both the English and metric systems, as are actually
necessary for a speedy application of the test:
It is admitted that this test is in itself a very complex proc-
ess, involving not only the ordinary skin sensations of touch,
but also calling into exercise the muscular and articular sensa-
tions. But this variety of sensory data, as well as further dif-
ferentiations due to individual variations, such as differences in
the thickness of the cuticle, and again lack of uniformity among
the subjects who were examined in relying upon the compo-
nent factors in the actual test of sizing—such, as for example,
may be brought about by one person's dependence in the test
upon pressing the shots between the fingers and thumb, while
another relies upon lightly rolling the contents of the bags—
will enter only remotely into the test from the point of view
herein taken, which is to determine whether deaf children, on
Size 2 3.70 mm. O.I.46 inches
Size 3 3. I5 mm. O.I28 inches
Size 4 2.99 mm. O.II8 inches
Size 5 2.89 mm. O.II4 inches
Size 6 2.79 mm. O.IIo inches
Size 7 2.66 mm. O.IO4 inches
Size 8 2.36 mm. O.O93 inches
Size 9 I.83 mm. o.O76 inches
Size Io I.75 mm. O.O69 inches
Size II I.52 mm. O.O6O inches
6O IXPERIMENTAL STUDIES
the average rank higher or lower than hearing children in this
very primitive and still in our day substantial mode of gaining
information.
The results of this test are presented in Table XVI. In this
the deaf children are compared directly with the hearing chil-
dren of their respective ages. The table is divided into two
main divisions, or parts. The main division on the left, for
both deaf and hearing, indicates the portion of the experiment
in which the standard is compared with shot of a smaller size,
and the other main division has reference to that part in which
the shot compared is larger than the standard. The sizes of the
shot sensed are given at the top of each column from I to XII,
and the results of comparative sensitivity under these headings
show the per cent of children who are able to sense one, two
and three size-differences.
As already indicated, differences in sensitivity of subjects
do not always run parallel to objective differences, but it is,
however, quite natural to make the inference that actual dif-
ferences in the sizes of shot discriminated measure to a degree
subjective differences in the sizing sensitivity of individuals, so
that a child who can discriminate size 6 from size 7, or size 6
from size 5, has a keener sense of touch than a child who can
only sense differences between two, three or more sizes.
Owing to the small number of cases, the girls and the boys,
respectively, are divided into three groups; first, those chil-
dren from 6 to 8 years; second, those from 9 to 12 years;
third, those between the ages of I3 and 18 years. The ages of
the groups are given in the first column of Table XVI, and in
the second column is presented the number of cases examined
in each group. For ready reference the recorded per cent of
correct answers in each instance is marked by Roman numerals.
Thus, in the third column, marked I, is recorded the per cent
number of children who correctly sensed a difference between
the sizes 6 and 7. In comparing, therefore, the deaf children
with the hearing of like ages, in this particular test, we exam-
ine columns I and IV, VII and X, for records of their re-
Spective abilities in dealing with one size; columns II and V,
VIII and XI, for differences of two sizes; and columns III
TABLE XVI.
PERCEPTION OF SIZE BY SENSE OF TOUCH.
Deaf children Hearing children Deaf children Hearing children
Ages No. of ..I. II. III. No. of IV. V. VI. VII. VIII. IX. X. XI. ' XII.
g cases | Size 6 || Size 6 || Size 6 cases | Size 6 Size 6 Size 6 || Size 6 Size 6 || Size 6 || Size 6 || Size 6 || Size 6
from from from from from from from from from from from from
size 7, size 8, size 9, size 7, size 8, size 9, size 5, size 4, size 3, size 5, size 4, size 3,
per Cent per cent per cent per cent per cent per cent || per cent per cent per cent per cent per cent per cent
BOYS
6. . . .8 17 23.5 76.5 | . . . . . . . . . . 5 60 40 | . . . . . . . . . . 21 68.4 10.6 80 l . . . . . . . . . . 20
9. . . 12 26 42.3 42.3 15.4 31 60 40 | . . . . . . . . . . 37.7 42.3 20 73 27 | . . . . . . . . . .
13. ... 18 32 56.2 43.8 . . . . . . . . . . 18 78 22 | . . . . . . . . . . 56.2 40.6 4.2 67 28 5
GIRLS
6. . . .8 10 40 60 l . . . . . . . . . . 9 67 33 . . . . . . . . . . 40 60 | . . . . . . . . . . 44 56 | . . . . . . . . . .
9. . . 12 18 61.1 38.9 . . . . . . . . . . 24 58.3 37.7 4. 55.6. 44.4 | . . . . . . . . . . 54 42 4
13. ... 18 28 60.7 28.6 10.7 17 70, 29.4 | . . . . . . . . . . 71.4 17.9 10.7 83 17 | . . . . . . . . . .
º



62 EXPERIMENTAL STUDIES
and VI, IX and XII, for the results secured when the test in-
volved actual differences of three sizes.
It is readily seen that at no age-group do so many deaf
children accurately sense small differences as their hearing
mates. Thus, in the 6 to 8 age-group of boys, 23.5 per cent
only of the deaf children gave correct answers in attempting
to sense a difference between sizes 6 and 7, whereas 60 per
cent of the hearing children of corresponding ages were able to
answer correctly (See columns I and IV), and in comparing
sizes 6 with size 5, the deaf and hearing children stand, re-
spectively, 21 and 80 per cents (columns VII and X).
Owing to the nature of the data in this Table, it is unnec-
cessary to discuss any more than the recorded abilities of the
children in dealing with differences of one size. (Columns I,
IV, VII, X). It is interesting, nevertheless, to note that where-
as I5.4 per cent of all deaf boys, in the age-group 9 to I2
years, are recorded as being able to perceive no smaller differ-
ences than three sizes (column III), there were no hearing
boys of the same age who were unable to detect size differences of
at least two.
It is, moreover, apparent that while sensitivity in this test
increases with age, there is a much greater increase observed
among the deaf boys and girls than among the hearing chil-
dren of comparable ages, for we see that the per cent stands,
respectively 23.5-42.3-56.2 and 21.-37.7-56.2 for the deaf boys,
as against 60.-6O.-78. and 80.-73.-67. for hearing boys (columns
I, VII, IV, X), and 40.-61. I-60.7 on one-half of the Table, and
4O-55.6-7I.4 on the other half for deaf girls, as against 67.58.3-
70.6 and 44.-54.-83. for hearing girls (columns I, VII, IV, X).
Besides a discussion of the differences due to increased ages
of the deaf and hearing children, it is interesting to note
whether our tables show any sex differences in this particular
test of sensitivity. It is apparent, to speak in general terms,
that deaf girls are more sensitive in this test than deaf boys,
while, on the other hand, among the hearing children, the ad-
vantage in sensitivity lies with the boys. (See especially age-
group 9 to I2 years, for deaf and hearing boys and girls). The
reasons for this are, however, difficult to point out. It may,
DEAF CHILDREN 63
indeed, be due to some fundamental difference between deaf and
hearing children; again differences of training and daily ex-
periences may affect their skill in reacting in this test, or we
may have to fall back on the observation that the number of
deaf children in each age-group is so small as to preclude
positive statements on this score.
For the very reasons, however, that the number of cases is
so comparatively small, and the data of the sizing-test are pre-
sented in terms of ranks of individuals, it is of some interest
to turn to the additional data subjoined, which show the num-
ber and per cent of children who are able to size differences as
TABLE XVII.
SIZING TEST (ACTIVE TOUCH).
... Showing the number and the per cent of children, who are able to sense
differences as indicated, the children being grouped without reference to age.
No ..I. II. III. Iv. v. VI.
of * } Size 6 Size 6 Size 6 Size 6 Size 6 Size 6
C3 SeS from from from from from from
size 7 size 8 size 9 size 5 size 4 size 3
Deaf boys, all
algeS. . . . . . . . . . 75 |33, or 44% |38, or 51% 4, or 5% |32, or 43% 35, or 47% 8, or 10%
Deaf girls, all
algeS. . . . . . . . . . 56 |32, or 57% |21, or 37% 3, or 6% |34, or 61% | 19, or 34% 3, or 5%
Boys and girls. 131 |65, or 50% |59, or 45% 7, or 5% |66, or 50% 54, or 41% |11, or 9%
Hearing boys,
all ages. . . . . . 54 |35, or 65% |19, or 35% | . . . . . . . . . . 40, or 74% | 12, or 22% 2, or 4%
Hearing girls,
all ages. . . . . . 51 |32, or 63% |18, or 35% | 1, or 2% |32, or 63% | 18, or 35% | 1, or 2%
Boys and girls. 105 |67, or 63.8%|37, or 35.2%| 1, or 1% 72, or 68.5%l 30, or 28% 3, or 3%
indicated in Table XVII, where the children are grouped with-
out reference to age. In this Table XVII it is more than
ever apparent that deaf children, as a group, are not so sen-
sitive as hearing children. Giving exact statement, it is seen
that only 50 per cent of the deaf children sensed the smaller
size differences (See columns I and IV of Table XVII), where-
as 68.5 per cent, or at least 63.8 per cent of the hearing boys
and girls, accurately detected a difference of one size. Of
course, the qualification should be made that the number of
children in the different age-groups are not equal. However,
because there are more children in the older age-groups than in
the younger, and again since sensitivity is observed to increase
with age, whatever advantage there is, lies with the deaf chil-
dren.
Again, by reason of the further groupings of children
64 EXPERIMIENTAL STUDIES
which this table makes, the sex differences of the deaf and
hearing children, already alluded to, become more significant.
Taking the deaf first in order, it will be seen that 44 per cent
of the boys gave correct answers to the test on one side, below
size 6, and again 43 per cent of the whole group were correct
for a difference of one size above size 6, whereas the deaf
girls gave 57 and 61 per cent, respectively, correct. The deaf
girls, as a group, although inferior to their hearing sisters in
sensitivity, are not so much below as the deaf boys in this par-
ticular. The hearing boys stand 65 and 74 per cent for One
point's discrimination, while 63 per cent of the hearing girls,
as a group, show ability to perceive differences of one size above
or below the standard. Moreover, from internal evidence in the
table, the deaf and hearing boys seem more variable in abilities
than the hearing and deaf girls.
Least Noticeable Differences in Lifted Weights.
Turning now to the third perception test, we come to con-
sider the child's power to discriminate small differences in lifted
weights, where the lifting or hefting is done by a free, full-arm
movement, such as occurs when a child passes alternately from
one weight to the other in lifting them from a table, upon
which they have been placed.
For the test series small wooden bottles of uniform size and
dimensions were employed. So far as external appearances
go, they could not be easily distinguished the one from the
other. The bottles were loaded to the required weight with a
filling of shot. They were then packed with paraffin and cotton,
so as to prevent any movement of the contents within, after
which they were carefully sealed. The series ran at intervals
of two grams from a weight of 8 grams to one of 32 grams. In
order it stood, 8, IO, I2, I4, 16, 18, 20, 22, 24, 26, 28, 30, 32
grams. With the 16 gram weight, which was used as a point
of departure, or standard, weights heavier and lighter were com-
pared; the I6 gram weight and the one heavier or lighter than
it, having been placed upon a table before the child, and he
asked to heft them, one after the other, and to indicate which of
the two was the heavier. Care was taken, however, to keep the
DEAF CHILDREN 65
child dependent upon actually sensed factors in hefting, and to
guard against his identification of the standard weight by extra-
neous signs. A comparable method of procedure was followed,
sometimes with weights heavier, sometimes with those lighter
than the standard, in irregular order, until the experimenter,
after several determinations around the standard weight, had
satisfied himself of the least noticeable difference in weight,
both lighter and heavier than the standard, that the child could
Se11Se.
In recording the data it seemed best in indicate simply which
weights the child could discriminate, accurately and invariably,
from the standard, or I6 gram weight.
Consequently the tables, showing the comparative Sensitivity
of deaf children for weight, like the preceding tables for siz–
ing, give the results in terms of the number and per cent of
boys and girls who were able to distinguish between (I) a
weight of 16 grams and one of 18 grams, (2) one of I6 grams
and one of 20 grams, (3) one of I6 and one of 22 grams on the
one side of the standard, and between (4) weights of I6 and I4.
grams, (5) I6 and I2 grams, and (6) I6 and IO grams, re-
spectively, on the other.
Such data as we were able to collect are recorded in Table
XVIII, arranged so as to show sex differences, and the com-
parative standing of deaf and hearing children, respectively, of
comparable ages. As in the preceding test, because of the pau-
city of numbers, it was deemed advisable to somewhat arbi-
trarily group the records according to age. Thus, in the first
group, we placed the records of the boys and girls ranging in
ages between 6 and 8, inclusively; in the second, the preadoles-
ents (9 to I2 years), while the last group is composed, for the
most part, of children beyond the age of puberty (13 to 18
years, inclusively).
Inasmuch as the primary interest in comparing hearing and
deaf children, with respect to this test, centers about the least
perceptible difference in weight, which, on the whole, the
groups, respectively, are able to sense, it is with the
parts of the data which indicate the number and per cent of
children making the smaller discriminations, that we are chiefly
66 EXPERIMENTAL STUDIES
concerned. Indeed, since the figures are, for the most part,
mutually exclusive, in casting up age, sea and group compar-
isons, we need consider only the data found in the columns in-
dicated by the Roman numerals I, IV, VII and X.
Examining critically now the data in the columns indicated,
it is to be noted that for the younger years (6 to 8) deaf boys
are rather strikingly inferior to their hearing mates in this
sense, while the converse holds in the case of the girls. In the
I6 and 18 gram set, 66.7 per cent of deaf boys were able to
make the discrimination invariably, as against 80 per cent of
the hearing boys. The figures for deaf and hearing girls are
66.7 per cent and 44.4 per cent, respectively. In the I6 and I4
gram set again 66.7 per cent of the deaf boys always rendered
correct judgments, while IOO per cent of the hearing boys were
able to do so. For deaf girls the figure is 71.4 per cent, against
66.7 per cent for hearing girls. The number of hearing chil-
dren, especially at these ages, is unfortunately small, so that
too much weight cannot be attached to the results.
In the next age-group (9 to I2 years) the numbers are lar-
ger, and the conclusions consequently a little more reliable.
Deaf boys now rank in muscular sensitivity above hearing boys,
the per cents being, for the 16-18 gram pair 88.4 and 74, re-
spectively, for the deaf and hearing boys, and for the 16-14
gram pair, 77.3 and 72, respectively, for the groups considered.
Between deaf and hearing girls of this age-group, the differ-
ences are discovered to be inconsequential. The figures for the
I6–18 gram pair are 53.3 and 54.0 per cent, respectively, and
for the I6–14 gram pair of weights, 64.2 and 58.3, per cent.
The groups of adolescents (13 to 18 years) are not so large;
but differences between the groups in the mental attitude in
which the test would be approached, ought to be less signifi-
cant than for the younger ages. (If this factor actually enters
into the test.) So far as the results go, no significant differ-
ences in muscular sensitivity between deaf and hearing boys
or deaf and hearing girls stand out. Deaf boys rank lower in
the I6-18 gram set than hearing boys, as is shown by the rela-
tive per cents who invariably rendered correct judgments, 60
per cent of the deaf and 66.7 per cent of the hearing boys, but this
TABLE XVIII.
PERCEPTION OF WEIGHT (ACTIVE).
*.
Deaf children Hearing children Deaf children Hearing children
Ages No. of I. II. • III. No. of IV. V. VI. VII. VIII. IX. X. XI. XII.
& C3 SeS 16 gms. | 16 gms. | 16 gms. cases | 16 gms. | 16 gms. 16 gms. 16 gms. | 16 gms. | 16 gms. | 16 gms. | 16 gms. | 16 gms.
from from from from from from from from from from from from
18 gms., | 20 gms., 22 gms., 18 gms., 20 gms., 22 gms., || 14 gms., | 12 gms., | 10 gms., | 14 gms., | 12 gms., | 10 gms.,
per cent per cent per cent per cent per cent per cent || per cent | per cent per cent per cent per cent | per cent
BOYS
6. ... 8 15 66.7 33.3 | . . . . . . . . . . 5 0.0 20.0 | . . . . . . . . . . 66.7 20.0 13.3 100.0 [ . . . . . . . . . . . . . . . . . . . . .
9.... 12 22 88.4 11.6 | . . . . . . . . . . 32 74.0 26-0 | . . . . . . . . . . 77.3 18.2 4.5 72.0 28 . . . . . . . . . .
13. ... 18 25 60.0 36.0 4 18 .7 33.3 | . . . . . . . . . . 64.0 32-0 | . . . . . . . . . . 61.0 33.3 5.7
GIRLS
... 8 9 66.7 33.3 | . . . . . . . . . . 9 44.4 44.4 11.2 71.4 28.6 * 9 s e s e a 66.7 33.3 | . . . . . . . . . .
9. . . . 12 15 53.3 46.7 | . . . . . . . . . . 24 54.0 46.0 ! . . . . . . . . . . 64.2 35.8 . . . . . . . . . . 58.3 41.7 . . . . . . . . . . .
13. ... 18 23 78.3 21-7 | . . . . . . . . . . 17 70. 6 29.4 | . . . . . . . . . . 69.6 26.1 4.3 70.6 29.4 | . . . . . . . . . .
;
S

68 EXPERIMENTAL STUDIES
inferiority is compensated for in the 16-14 gram pair of weights,
where the per cent of deaf who sensed a difference was 64 as
against 61 for the boys with hearing. In the case of the girls,
the deaf have a slight advantage in the I6-18 gram pair, 78.3
per cent making correct judgments, as opposed to 70.6 per cent
of the hearing girls, but with the 16-14 gram set 69.6 per cent
of the deaf girls invariably gave correct replies and 70.6 per
cent of the hearing girls.
Looking for differences between the boys and girls as re-
gards sensitivity for lifted weights, among deaf children it is
discovered that for the younger years, the sexes do not differ
very significantly, the same per cent of boys and girls sensing
a weight difference between 16 and 18 grams, and only a slight
advantage being shown in favor of the girls in the I6-14 gram
Set. Among hearing children of the same ages, on the con-
trary, the boys show up markedly better than the girls, 80 per
cent sensing the difference in the 18–16 gram set, and Ioo per
cent in the I6-14 gram set, as against 44.4 per cent and 66.7 per
cent, respectively, for the two sets, in the case of the girls.
Comparing the sexes in the second age-group (9 to I2 years
old), we find the boys uniformly better both as regards deaf
and hearing children. The figures run as follows:
Deaf. Hearing.
I6-18 set. I6-14 set. I6-18 set. I6–14 set.
Per cent. Per cent. Per cent. Per cent.
Boys . . . . . . . . . . 88.4 77.3 74.O 72.O.
Girls . . . . . . . . . . 53.3 64.2 54.O 58.3
Conditions are reversed when we turn to the older group
of boys and girls, those between the ages of 13 and 18 years, as
may be seen from the following summary:
Deaf. Hearing.
I6–18 set. I6-14 set. I6-18 set. I6-14 set.
Per cent. Per cent. Per cent. Per cent.
Boys . . . . . . e ſº º e 6O 64 66.7 6I.O.
Girls . . . . . . e e º 'º 78.3 69.6 70.6 70.6.
Thus, although some sex differences were discovered, when
age groups were considered separately, taken all together the
group tendencies counteract one another, so as to obliterate any
DEAF CHILDREN 69
conclusive evidences of such tendencies in one direction or an-
other.
Looking for differences in sensitivity that might come with
increased age, the data also offer nothing very promising. The
I6-18 set does show such a tendency in the case of the hearing
girls, but the exact converse is shown, with both this weight set
and the I6-14 gram set in the case of the hearing boys. The
data for the deaf are altogether too irregularly distributed to
warrant any general conclusion. A larger representation in each
age-group, however, might bring out some decided evidence of
improvement in the weight sensitivity with age, but it is equally
likely that the responsible factor is the elementary nature of the
teSt.
PERCEPTION OF WEIGHT (ACTIVE).
BRIEF SUMMARY OF TABLE XVIII.

No. of 16 grs. from 16 grs. from
Ca,SeS 18 grs., 14 grS.,
per Cent per cent
Deaf boys, all ages. . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 71 69.3
Deaf girls, all ages. . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 68. 1 68.1
Boys and girls (deaf) . . . . . . . . . . . . . . . . . . . . . . . . ‘. . 109 69.7 68.8
Hearing boys, all ages. . . . . . . . . . . . . . . . . . . . . . . . 55 72.9 70. 9
Hearing girls, all ages . . . . . . . . . . . . . . . . . . . . . . . 50 58.0 64.0
Boys and girls (hearing) . . . . . . . . . . . . . . . . . . . . . . 105 65.7 67.6
In the foregoing discussion, because the numbers at each
age are so small, the children were placed in three groups, and,
to a degree, the disadvantages due to small numbers were over-
come, though, to be sure, not wholly obviated. There are sev-
eral advantages, therefore, in comparing the deaf boys and girls
as a whole, irrespective of age, with hearing boys and girls
under like conditions, as well as to compare our deaf children
as a whole, with their hearing companions. The results of such
groupings are presented in Table XVIII (Summary), and we
accordingly see that, in sensing a difference of two grams be-
tween two lifted weights, 71 per cent and again 69 per cent of
the deaf boys gave correct responses, as against 73 per cent and
7I per cent of the number of hearing boys examined. Further,
68 per cent and again 68 per cent of all deaf girls correctly
sensed a difference of two grams, whereas only 58 per cent and
64 per cent of the hearing girls were equally sensitive. Finally,
70 EXPERIMENTAL STUDIES
in the group representing boys and girls, we see in comparing
the deaf children with hearing children in this test that 70 per
cent in one instance and 69 per cent in the other case, of all the
deaf girls examined, accurately sensed the actual differences of
two grams in the weights presented, whereas 66 per cent and
again 68 per cent of the whole number of hearing girls ex-
amined, were able to note the same differences. Deaf girls,
therefore, as a whole, irrespective of age, rank better than their
hearing sisters, but, on the contrary, deaf boys rank more poor-
ly, and, taking boys and girls together, irrespective of age,
while the advantage lies slightly with the deaf, their superiority
over their hearing companions is not sufficiently marked, con-
sidering the paucity of numbers, to warrant us in asserting that
the difference is real.
Memory.
Among the different materials employed for testing the im-
mediate sense-memory, the ordinary Arabic numerals must be
considered among the best, both from the point of view of con-
venience and reliability of results. Numerals are symbols used
in our civilization, and inasmuch as they are in themselves rel-
atively non-significant, they can be employed readily in making
a comparative study of one kind of memory. A numeral is not
liable to have more associations with one individual than with
another. To test the visual sense-memory, cards on which were
placed in rows the ordinary Arabic numerals were held before
the child, after which the cards were removed and the child
was required to reproduce the numerals which were seen, in the
exact order in which they appeared on the cards, either orally
or in writing. In order to avoid groupings the child read the
numerals from right to left, and the greatest number which he
could accurately reproduce was considered a measure of his vis-
ual sense-memory. In the second part of the test the numerals
were repeated to the child by the experimenter, care being taken
that there should be no rhythm which could induce groupings;
and the child reproduced the numerals as before.
The test thus consisted of the two parts (I) pure visual
sense-memory, (2) indirect visual-memory, read from the lips
of the experimenter. This latter also afforded a test of the
DEAF CHILDREN 71
child’s ability to read unrelated word-symbols from the lips of
the speaker.
TABLE XIX.
MEMORY SPAN.
Age Visual Lip reading
Y IM Number *
rS OS Deaf Normal Deaf
7. . . . . . 6 10 3.3 5 3.2
8. . . . . . 6 13 3.3 5 3.0
9. . . . . . 6 13 3.7 6 3.1
10. . . . . . 6 17 4.1 6 3.7
11. . . . . . 6 12 4.4 6 4.0
12. . . . . . 6 7 4.7 7 4.4
13. . . . . . 6 12 4.8 7 4.2
14. . . . . . 6 12 5.2 7 4.7
15. . . . . . 6 17 4.9 7 4 3
16. . . . . . 6 6 5.7 7 4.3
17. . . . . . 6 4 5.5 7 4.7
18. . . . . . 6 2 5.0 7 4.0
19. . . . . . 6 2 5.0 S 5.0
In Table XIX are given the memory spans of deaf and nor-
mal hearing children in parallel columns. It is seen that where-
as the hearing child of from seven to eight years has, on the
average, a memory span of five numerals, the deaf child has
a memory span of but three numerals, and while the hearing
children from 12 to 19 years of age have, on the average, a
memory span of seven numerals, the deaf children can remem-
ber but four or five. It is further seen that there is but a slight
superiority when the numerals are directly seen in comparison
with the indirect reading, or reading from the lips. This offers
a suggestion that lip-reading has kept pace with the child’s
general development.
Taking all these tests and observations together for the
purpose of estimating the mental status of the deaf children, we
see that it is possible to get a general view of their compara-
tive abilities with respect to particular mental powers. But when
these mental functions are all taken together they do not ex-
haust the content of such a highly complex thing as mentality.
It is necessary always to bear in mind what we really mean in
everyday life by mental capability or mentality. Is it the abil-
ity to speak, to read, to write, to follow directions, carry on Or-
dinary functions of life without assistance, or does it mean
the capacity an individual has to improve by training and prac-
tice and the relative facility with which training can be accom-
72 EXPERIMENTAL STUDIES
plished P. With the deaf child we necessarily must place more
emphasis on the latter, i. e., the teachableness of the individual.
Sometimes he cannot speak, read, write or follow directions as
given by us, because he lacks the symbols—language, the me-
dium by which we, as hearing individuals, indicate directions.
And until he learns the symbols and the meanings attached to
them it is impossible to test him by such standards. Such a pro-
cedure would be as unfair as to give the unclassified man direc-
tions in Greek, and then classify him as mentally deficient be-
cause he was unable to follow them.
Therefore, the chief criterion used in testing the mentality
of the children in the deaf rooms was their amenability to train-
ing. The question put to ourselves was this: Has the child
sufficient mentality so that, with the training he shall receive in
school, he will be partially or wholly self-supporting when he has
reached maturity, or will he likely become a ward of the State?
Such a criterion naturally gives us three somewhat distinct
classes, which may be called:
I. Mentally Normal: Those who will be wholly self-supe
porting at maturity.
2. Slightly Sub-Normal: Those who will not be, in all proba-
bility, wholly self-supporting when they attain to man-
hood and womanhood, but may require some external
direction in any occupation which they may take up, or
in the general conduct of life.
3. Those who will probably require direction and care, and
hence must be regarded as wards of the State.
We find, then, that as thus classified, the deaf children are
distributed in the following order, and these ratings are made
partly on the basis of the personal judgment of the examiner—
being the result of an hour's careful inspection of the child’s
work—but more particularly based on the child’s performance
in the mental tests given:
Number of Normal Mentality . . . . . . . . . . . . . . . . . . . . . . . . . I73
Number Slightly Retarded or Sub-Normal. . . . . . . . . . . . . . . II
Number Mentally Defective, or of those who do not give
promise of being at least partially self-supporting at
maturity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O
Total number examined . . . . . . . . . . . . . . . . . . . . . . . . . 184
DEAF CHILDREN 73
It is thus seen that of the total number of 184 children in
attendance at the deaf schools, only II, or 6 per cent, are SO
backward mentally that they do not give hope of being able to
support themselves independently after they have reached the
ages of manhood and womanhood, and further, there is not a
single individual whom it seems the State will have to take
over as a ward.* It may be noted that this number, 6 per cent,
of the group of deaf children who are accounted as Sub-Nor-
mal, is considerably higher than we find among all School chil-
dren, among whom 5 or 6 per thousand are regarded as dis-
tinctly Sub-Normal in the very technical use of the word. This
rather large number is doubtless intimately related to, if not,
indeed, caused by, the diseases and disorders that bring about
impairment of hearing in such a large number of the deaf chil-
dren.
*This does not mean that there are no mentally-defective and
feeble-minded children among the deaf in Chicago, but that in the pre-
liminary examination of deaf children, by this Department, for admis-
sion to the rooms for the instruction of the deaf, the parents of those
who were too low a grade of mentality to profit by such instruction as
the public schools afford, were advised to send their children to institu-
tions where special province is the care of such cases. In no Case Were
feeble-minded children permitted to enroll in the classes for the deaf.
SUMMARY AND SUGGESTIONS.
In making a brief resumé of the study heretofore presented
in detail, the attempt will be to give the results in barest out-
line only and then add the suggestions which come to mind as
a consequence of these results.
It was pointed out that the intimate relation between the
mental and physical life of children made it necessary, if the
study should be full and complete, that these aspects of the
child's life should receive careful consideration. Further, by
way of introduction, it was indicated that owing to the extreme
timidity and narrow social life of deaf children, time, patience
and skill were required in order to elicit any responses which
would be indicative and characteristic of this type of children.
The hearing ability of the deaf was found to vary by degrees
from absolute silence and insensibility to any sounds whatever,
to a condition of semi-deficiency where the auditory acuity was
too defective for the child to carry on his work in the grades
with hearing children, i. e., it was found that deaf children do
not form a distinct group. There are all grades of hearing
power and the classification r tight better be based on the use
which the power of hearing serves in social communication.
It was found that only thirty-two per cent of the whole num-
ber of deaf children were totally deaf; nineteen per cent were
found to be practically deaf, that is, they gave no hope of ever
being able to hear the human voice, even with the aid of mechan-
ical instruments. There were thirty per cent who were unable
to hear speech, but could hear loud noises. This and the next
group, which contains fourteen per cent, who could hear loud
speech, form a class which may for certain purposes be grouped
together. In comparing the intensity of the noise which some
of these children are able to hear, with that which some adults,
whose hearing became impaired after maturity, are capable of
appreciating and responding to intelligently, it is found that
there are deaf children who hear no speech at all whose absolute
hearing power is superior to that of some of those who hear and
DEAF CHILDREN 75
depend on speech. This difference in speech-hearing ability
seems to be due entirely to the absence of the habit of attention
to the significance of sound-sensations on the part of deaf chil-
dren. These considerations offer the suggestion that if some
means were employed of intensifying speech-sounds and in this
way create the habit of attending to sound sensations of speech,
in many cases the hearing of the deaf children might be so im-
proved that to a considerable extent they could be made depend-
ent on hearing in carrying on social intercourse. Of course, such
a habit could not be developed short of many months of training
and for this reason we found it impracticable to make the test of
the value of any apparatus on the market for this purpose. Differ-
ent devices of hearing apparatus are very highly recommended,
but we are not aware that any of these have been extensively
tried anywhere in Chicago. Not having given any apparatus
for developing the power of hearing a careful and crucial test,
the Child Study Department does not therefore feel justified in
recommending any particular form or device, but we do think
that some apparatus should be given a trial, especially since
twenty per cent of all children in attendance at different rooms
for deaf children give the hope of having their hearing sufficient-
ly improved to hear conversation.
Passing to the part of the investigation relating to the speech
and speech-reading of the deaf, the main consideration in rela-
tion to the time that had been spent in acquiring it, was the
character of the speech. Necessarily the character of the deaf
child's speech depends on the amount of training he has received.
This aggregate of training, in a great majority of cases, can be
measured by the time the child has been in school. Waiving all
consideration of those children who possess sufficient hearing to
enable them to speak in the natural way and those who lost their
hearing after they had learned to speak, thus limiting ourselves
to those who are born deaf and to those who lost their hearing
early in life, we find that after a period of three years in school,
twenty-five per cent have speech which is normal, or nearly so;
there are fifty-three per cent whose speech is defective and twen-
ty-two per cent in whom speech is practically wanting, i. e., less
than fifty words.
76 EXPERIMENTAL STUDIES
To repeat here, for the sake of clearness, a statement made
in the body of the report, when we speak of a deaf child's speech
as normal, we mean that his articulation and tonal quality are
good, but not that his range of vocabulary is equal to that of a
hearing child of the same age. A latitude in this particular
must be allowed of from three to five years. After a school
period of five years we find that forty-two per cent of those
born deaf or those who lost their hearing early in life, have
speech which is normal or nearly so, fifty-eight per cent have
speech which is more or less defective and not a single indi-
vidual was found who could not intelligently talk at least fifty
words. At the end of seven years of school training forty-seven
per cent were found to have normal speech and fifty-three per
cent with speech somewhat defective. Only four individuals
had been in school as long as ten years. Of these one had some
hearing; the other three, congenital cases, were found to have
speech which was normal.
From the foregoing it appears that at least where conditions
obtain as they do in our day schools for deaf children, more than
three years of training is necessary in order that the average
deaf child shall acquire speech, but that almost every child (so
far as our results indicate) is able to learn the use of speech
and speech-reading after a school period of five years.
It is unfortunate that the school has no control of the home
and social conditions of children and especially the deaf. If it
were possible to control, in a measure, the food, rest, exercise
and language environment of the deaf child, and if it were pos-
sible to enlist the co-operation of parents in employing school
methods of communicating with their children, whatever these
methods may be, the acquirement of any language would be
greatly facilitated. In fact, it is found to be so with the method
now in use, in those homes where parents are eager to learn and
adopt the school room practices. Children from better homes,
it was observed, were from two to four years in advance of those
who came from less favored homes. However, it is doubtful
whether many consider the time element as after all the factor
of paramount importance. Probably the most vital consideration
is whether the great majority of deaf children or all deaf chil-
DEAF CHILIDREN 77
dren can acquire speech even after ten years of training, and if
(as shown by the results of our investigations) all children, after
they have been in school from five to ten years, do gain a suffi-
cient mastery of speech to carry on intercourse with hearing
people, then the question arises whether the oral method be of
more service to them than the manual in the succeeding forty
or fifty years, while they are earning a livelihood and are getting
the most out of life that it has to offer. But as before men-
tioned, the problem of the relative value of oral or manual lan-
guage as a means and medium of intercourse in the Social and
industrial world is one which it was impossible for us to evaluate
and on this account we prefer to leave it untouched.
There are, however, certain suggestions that refer more spe-
cifically to those who are engaged in teaching the deaf, which
we feel ought to be made. Where oral speech is to be taught,
it is undoubtedly the part of wisdom to take cues from nature's
ways of dealing with normal hearing children. Every effort
should be made to ascertain as early as possible in the life of
these children the nature and degree of deafness, together with
the causes which brought about the defect, so that perchance
something may be done to remedy or improve the conditions.
In the case of the congenital deaf and those who lost their hear-
ing before the middle of the second year, the ideal procedure
would be to have instruction begin as nearly as possible after
the time that speech tendencies normally develop.” It is one of
the laws of instinctive behavior that if tendencies to activity are
not utilized at the time they appear in nature's program, they
fade and the activity must be developed anew at the expense of
considerable effort, and there is no reason why this does not
apply to speech as well as to other human activities. Whether
kindergartens should form a part of the public school system of
education for the deaf is a matter pertaining wholly to public
policy and administration, but certain it is that those few chil-
dren now in the deaf schools who have had the advantage of
early instruction are far in advance of the less favored chil-
dren in their power to adjust themselves to the educational forces
at work in our social life.
*Cf. Kerr Archives Of Otol. 33: 129.
78 EXPERIMENTAL STUDIES
The important part which hearing plays in the acquiring of
speech is another element that cannot be too much emphasized.
By all means advantage should be taken of the hearing power
which the child has, however little this may be. Especially im-
portant is this in the case of those children whose hearing be-
came impaired through disease after speech had been acquired.
Unless the hearing factor is utilized, there is a tendency for con-
fusion to result from the inability of the child to distinguish the
hearing images from the imperfectly formed visual images. (Of
course reference is here made only to language images.)
In the matter of sight, which is so overwhelmingly impor-
tant in the life of the deaf child instructed in the oral method,
who must depend on this sense almost entirely, the investigation
showed very happily that the visual acuity of the deaf is on the
whole as good as that of the hearing children. Nor is the rela-
tive number of those suffering from decidedly defective vision
greater in the former group than it is in the latter. The sug-
gestion is pertinent here that the eyes of the deaf children should
receive frequent testing so as to obviate any permanent impair-
ment of vision which may result in consequence of eye strains.
In comparing the stature of the deaf with that of hearing
children, it was discovered that both deaf boys and deaf girls
were, on the whole, shorter in stature for corresponding years,
and both sexes among the deaf have shorter bodies in proportion
to the total height, than hearing boys and girls. With respect to
weight, deaf boys were slightly lighter, on the whole, than their
hearing fellows, but on the other hand, deaf girls were slightly
heavier, age for age, than hearing girls. Deaf children in gen-
eral, of both sexes, were found to have smaller heads than nor-
mal hearing children, when as a criterion of size, the length-
breadth product is employed. On the average, too, they were
more brachiocephalic (broader headed.)
The most striking comparative inferiority of the deaf was
pointed out in connection with the data on lung capacity. Deaf
boys as a group, it was seen, stood about on a par with the
twenty-five percentile group of hearing boys; and the deaf girls
had about the same rank as the thirty-five percentiles of their
hearing sisters. In general average, deaf boys and girls rank
DEAF CHILDREN 79
seventy-five and eighty-five per cent, respectively, of the norms
for hearing children of their respective sexes. It is thus seen
that the effect of sedentary life is especially marked in diminish-
ing the vital capacity of the deaf. Of course, speech normally
has a tendency to develop lung power, but the deaf child suffers
from the deprivation of this as well as from the deficiency of
physical exercises, so that his blood is insufficiently aerated and
Oxydized, giving rise to anaemic conditions with all their attend-
ant evils.
Taking as a measure of strength, the ability to compress an
adjustable dynamometer, with each hand separately, it was found
that deaf boys, although slightly stronger than hearing boys
during their younger years, with the on-coming of adolescence,
showed a marked inferiority, and this was equally palpable in the
case of the less used and stronger hands. Between deaf and
hearing girls no significant difference stood out, and this, as
previously intimated, is but natural to expect. Hearing girls
are much less given to activity, as a whole, than hearing boys,
but that between hearing and deaf girls is probably not such as
to carry significant weight. Further, in the way of indicating
strength differences between the two groups of children, may
also be employed the grip indices, i. e., the fraction which the
weaker hand is of the stronger in each individual case, on the
average. Here again, there was found to be no significant dif-
ference between the grip indices of deaf and hearing girls; on
the contrary, deaf boys were found to be less ambidexterous
during the pre-adolesent years, but more ambidexterous after
the age of maturing, than hearing boys.
Taking as another measure of bodily efficiency, the quickness
with which a child is able to perform voluntary co-ordinated
movements as determined by the number of taps which can be
made in thirty seconds, it was found that at no age was the
average for deaf boys equal to the average of hearing boys,
with the right hand, and with the left hand the difference in
motor ability in favor of the hearing boys is still more apparent.
Deaf girls in the case of both hands, were found strikingly in-
ferior to hearing girls, and at no age is the average performance
of the deaf significantly higher than that of their hearing sis-
s
:
*
i
8O EXPERIMENTAL STUDIES
ters. It was further noted that both deaf boys and deaf girls
of I2 years and older more nearly approached, the standings of
hearing children in tests of motor ability than the deaf of young-
er years. Furthermore, while the grip indices showed deaf boys
approaching maturity only, to be more ambidexterous than hear-
ing boys, the motor ability indices showed that the deaf of both
sexes, at all ages, are more ambidexterous on the average than
their hearing companions. It may be added, too, that this latter
index is, all in all, a better criterion of manual selectiveness than
that of grip. The relative standing then, of deaf children as a
class, in comparison with hearing children, was found to be even
less favorable, where rapidity of movement is involved, than was
apparent in the measurements of stature and weight, and only
slightly better than their relative standing in lung capacity.
By way of accounting for the more favorable showing of
the deaf children of more mature years, it was pointed out that
there seemed to be some intimate relation between an increased
variety of mental content and growth in motility, that is, accord-
ing to this view we should expect, with increased mental train-
ing, a greater degree of motor activity. By this indirect means,
therefore, the outflow of significant motor energy is enhanced.
But the problem of increasing bodily efficiencies should be at-
tacked directly. Certain provisions should be made to develop
the bodies of the deaf children. Their tendencies to be inert and
inactive should be counteracted or overcome. Considerable en-
couragement or stimulation is necessary to bring about continual
increase in bodily activity in order that their movements may ap-
proach that free and unstrained type of the normal hearing chil-
dren in their plays and home life. These large, free and easy
movements have, besides the advantage of developing and main-
taining the physical tone, the added value of furnishing stimula-
tion to mental growth. On this account, deaf children should be
encouraged to participate in the spontaneous out-of-door games
of hearing children as far as they are able, i. e., the plays of
the door-yard and of the street. Likewise, the periods of desk
work in the schools, especially for children under 12 years of age
should be as short as possible and the emphasis should be placed
tº-" DEAF CHILDREN 8I
upon the gross physical activities which are called into play in
their marches, games and constructive arts.
In turning to the more distinctly mental features of the in-
vestigation, the results show the deaf to be equal to normal hear-
ing children in the more elementary functions, such as imitation
and suggestibility, which are, to be sure, extremely elementary
and fundamental in character, but in the higher functions they
were found to be generally inferior. In the first test, for which
measurements were received—the “A-Test”—deaf boys as well as
deaf girls of all ages, are found to rank from three to four years
below hearing children, both as regards the time of discrimina-
tion and accuracy, in selecting one symbol from others of its
kind in a page of printed matter. A smaller per cent of deaf
children of both sexes than hearing children were found to be
able to discriminate the smallest differences in size, and in heft-
ing or sensing small differences in weight, probably no differences
obtain between the two classes of children. Deaf boys were
found to be slightly inferior to hearing boys in general, whereas
deaf girls were discovered to be generally superior to the hear-
ing. Discriminations made in the latter test (weight) are based
on shocks of differences into which a comparison with a con-
Scious standard weight-image is not thought to enter, in spite of
many contentions to the contrary, that is, the sensory data are
relatively less complicated than are those which enter into the
sizing test, and hence the weight test, like those of imitation and
sensibility, would be less liable to indicate individual differences
than the test calling for discrimination of size.
With regard to immediate sense-memory, which was the
only aspect of that important function which it was found prac-
ticable to employ on these children, it was pointed out that at
all ages, the memory span of the deaf averages about two nu-
merals less that that for hearing children, about the same rela-
tive inferiority that was observed in the case of the “A-Test.”
This inferiority of the deaf on the mental side perhaps means
no more than that the child is from three to four years less
mature than the hearing child of his age, and that his date of
maturing will be correspondingly delayed. It does not neces-
Sarily mean that, adult deaf individuals will be much inferior in
82 EXPERIMIENTAL STUDIES
mental comprehension and initiative to hearing adults. Indeed,
this mental retardation may be due to conditions in training,
and were the deaf child’s instruction begun in infancy instead
of at six years, the difference might be reduced or even elimi-
nated.
The problem of determining the number of deaf children
who are sub-normal, using a relatively pure mental standard, pre-
sents difficulties which we find it impossible to meet. One can
never determine just how much training a deaf child has had.
It is found much more feasible and practicable to employ as a
criterion the individual’s susceptibility to training. On this ba-
sis the investigation showed that there are but 6 per cent of
those in the rooms for deaf children who do not give promise
of being able to at least support themselves on reaching ma-
turity. And even these 6 per cent of the total number, will be
at least partially self-supporting; that is, able to earn a live-
lihood under direction. Further, not one was found whom it
would seem that the State must eventually take over as a ward.
The question of grading the deaf children is one that merits
consideration, and it seems highly desirable to have the chil-
dren well classified. Although individual instruction undoubt-
edly has many advantages over class work, nevertheless the
stimulus that comes from companionship with their mates in
a class exercise has a decided educational value. This associa-
tion without doubt goes far to incite, continue and cultivate
tendencies to express and communicate ideas. It would also
tend to prevent the too close dependence of children upon the
teacher's initiative, and to avoid the narrowing effects ensuing
from their fitting responses only to that which is expected or
demanded of them. In day schools where the children are dis-
persed over the city, proper classification is of course a puzzling
problem.
Commendable efforts have already been made in the public
day Schools for the teaching of the deaf in Chicago, in estab-
lishing within certain districts of the city centers where a con-
siderable number of deaf children are collected, making it possi-
ble to grade and classify children according to age, natural apti-
tude and school experience. But there is the additional desid-
- DEAF CHILDREN 83
him. of a proper Course of Study for the deaf. As in the
case of instruction of hearing children, there should be pro-
vided for deaf children, adapted to different years of their
School training, a certain definite body of information with
which teachers should be expected to make the children con-
versant. This is especially important in view of the fact that
it becomes necessary sometimes to transfer a deaf child from a
school in one part of the city to another. It thus ought to be
possible to have a certain repertoire of words and activities
which all deaf children should acquire during their first year
of school life, and in the same way for the following three or
four years. The saving of the teacher's time and energy in
duplicating work already done, in discovering the amount and
character of the previous training of the child, would be con-
siderable, and a decided step in advance would have been taken
in the direction of a proper grading of the deaf.
In offering the above experimental study of the compara-
tive physical and mental life of the deaf there are, of course,
many psychological and educational problems which have not
been touched upon. The foregoing is, however, presented with
the hope that it will throw considerable new light upon a prob-
lem which has hitherto been approached only from the stand-
point of theory and personal experience.
APPENDIX.
HISTORICAL NOTES.
So far as the Department of Child Study is aware, no
scientific study has ever been undertaken with the same object
in view, similar methods of procedure and with comparable
groups of children. Reference should, however, be made to Dr.
Love's studies * of fifty-four deaf children of the Glasgow In-
stitution in 1896, and their reported standing as compared with
boys of corresponding ages in the public Schools of that city.
The statistics on the physical characteristics of the children
(grouped at ages 15, 13, II and 9 years respectively), relating to
height, weight, circumstances of head and chest, seem to show
that they compare favorably with the normal hearing children
of corresponding ages, but the numbers are so small as to render
it very unsafe to generalize the findings on this special group
or to compare the results obtained with those of other workers.
The same is true in referring to the mental qualities of the deaf
children, with the added stricture that no ultra-school tests were
given. Classifications of mental status were based on observa-
tions and estimates of the teachers and no check is presented to
us of the personal equation of the observers whereby compari-
sons can be made between the mentality of these children and
any other selected group of deaf children.
Again one must note Binet’s work “” on the head measure-
ments of deaf children at the National Institute of Asnières,
France, in 1901. To these cephalic measurements should be
added, as indeed they were incorporated by the author, the sta-
tistics previously published by the attending physician to the in-
stitution, Dr. St. Hilaire *** on height, weight, lung capacity,
thoracic perimeter, strength of hand grip, circumference of head,
in every item of which the deaf children are recorded as in-
*J. Kerr Love, Deaf Mutism, 1896.
**Alfred Binet, Les Proportion du Crane chez Sourds-Meuts
L'Annee Psychologique, VIII, 1901; 385.
***Etienne Saint-Hilaire, La Surdi-Mutité, Étude Medicale, 1900.
86 APPENDIX
ferior to the normal hearing children of the same ages. The spe-
cific object of this study was to note cephalic changes in a com-
parison of the three groups according to age of the children ex-
amined. The shape of the heads of deaf children between five
and seven years was compared with the group nine to eleven
years, at which time the transformations evidenced by the vari-
ous diameters were pronounced, and these two groups were, in
turn, compared with the older groups, ranging in age from fifteen
to seventeen years. The comparative status of the deaf and
hearing children in these French institutions will be referred to
on a later page of this study. Any attempt to draw direct com-
parisons between groups of children must always be open to
certain reservations, but in this case it may be noted at once that
the deaf children attending the public day schools of Chicago
are a specially selected group, due to the preliminary entrance
examinations to these rooms which are given by this depart-
ment.
Dr. Ferrai, in 1902, made some comparative psychological
experiments * on twenty-four deaf children and twenty-two
normal orphaned children from socially comparable institu-
tions in Rome. The recorded results of the mental tests which
dealt, it should be noted, only with simple and complex memory,
ought to be of the greatest importance, but unfortunately they
are not of such a character as to show anything more than dif-
ferences due to training and environment. The general conclu-
sions exhibit pretty much what might be expected from the ma-
terial presented—that the deaf-mutes have a memory much in-
ferior to hearing children, and give evidence of much greater
improvement and progress during a definite period, because in-
deed, there is greater possibility of rapid improvement in their
case before the psychological limits are reached with the subject
matter at hand.
The study made by Schaefer and Mahner (**) of four
deaf, four blind and four normal hearing children is likewise
of interest, mainly for the attempt to establish direct compari-
sons between these special and variant groups of children. The
*Dr. Carlo Ferrai, Recerchi comparative Psicologia sperimentale
sui Sordo muiti. Intern. Archiv fur Schulhygiene. Band I, heft 4,
**Ztsch. f. Psych., 38; 1905, pp. 1-23,
APPENDIX 87
results are, however, vitiated by the fact that none of the deafs
were congenital, but became afflicted between the ages of 2 to
9 years. Furthermore, the attempt to make comparisons be-
tween the deaf children at each age and the normal hearing chil-
dren two years younger may have seemed suggestive for the
special group of institutions investigated, but certainly cannot
be supposed to yield results susceptible of very general applica-
tion. -
The somewhat intensive study of Dr. Decroly and Mme.
Degand on visual memory of seven deaf children is in a
measure deserving of special mention for its insistence upon
Specifically psychological methods of attacking the problem of
the development of the deaf. The deaf children who were com-
pared with normal hearing children are reported as not of equal
ages in each instance, and consequently no true index of the rate
of natural mental maturing is given us.
Such an important investigation as Dr. F. Danzieger’s
of the 286 deaf mutes of the institution at Ratibor, Germany, deals
as the title shows, specifically with malformations of palate and
its relation to nose, eye and ear defects, but in general it can-
vasses the characteristics of the family medium into which deaf
children are born—the prevalence of deafness in the blood rela-
tions and the diffused neuropathic tendencies of the near-of-kin.
It may be described as a study which is largely taken up with a
discussion and comparison of groups of deaf children with one
another and not of deaf children with hearing children. These
groups are divided on the basis of the casual factors of deafness
and also more or less upon the time of appearance of the afflic-
tion.
-
*L'Annee Psychol. (1906), Vol. 13; p. 128.
**Dr. F. Danzieger, “Die Missbildungen des Gaumens und ihr
Zusammenhang mit Nase, Auge, u. Ohr,” Wiesbaden, 1900,
APPENDIX
A COMPARISON
OF DEAF AND HEARING BOYS OF CHICAGO AND PARIS.

10 years 12 years 14 years
Features IPer Per Per
examined Cent cent cent
Deaf | Hear- which | Deaf | Hear- which | Deaf | Hear- which
IIlg. deaf 111g deaf 111g deaf
is of is of is of
hearing hearing hearing
iº IIT IIT III III, mm. I mm. II1111, IT1111,
Height |Chicago ...|1335.4! 1330.3 || 100.4 |1370.2] 1418.9 96.5 |1528.1| 1547.4 98.9
Paris...... 1243.0|| 1340.0 92.7 |1310.0|| 1370.0 94.9 |1430.0|| 1510.0 94.7
º kgs. I kgs. kgs. kgs. kgs. kgs.
Weight |Chicago ...| 28.18, 29.3 95.8 || 30.4 || 35.6 85.3 40.09| 44.7 89.5
Paris . . . . . . 27.47| 31. S8.6 |32.24 || 33.0 97.9 || 39.17; 41.0 95 5
Cll. Cl1. Cl1. Cll, Cl1. Cll.
Lung & CIT). CIT1. CIIl, CII1, CIIl. CIIle
capacity |Shicago 1466 | 1659 88.3 || 1704 || 1956 87.1 21.71 || 2527 85.9
Paris . . . . . . 1000 | 1670 59.8 || 1190 | 1800 66.1 || 1741 | 2030 85.7
Circum. IIT IIle
O Chicago ... 527 | . . . . . . . . . . . . . . . . . 521,2]. . . . . . . . . . . . . . . . 539.3] . . . . . . . . . . . . . . . . .
Head Paris...... 508 521 97.3 || 519.0| 533 97.3 529.0| 533 99.2
Chicago kgs. I kgs. kgs. I kgs. kgs. kgs.
R. H. . . . 19.5 17.7 108.0 | 21.7 || 22.4 92.4 || 28.9 || 30.4 95.0
Hand L. H. . . . 17.8 16.6 107.0 20.7 20.6 100.0 28.5 28.04 || 101.8
g|T1p Paris
. H. . . . 12.87; 17.5 73.5 || 17.5 21.12 || 82.8 || 23.66. 25.45 92.9
L. H. . . . 13.37; 17.0 78.6 | 16.6 19.5 85.1 23.0 21.18 95.4
The direct comparison of the Deaf and Hearing Boys of Chicago and Paris,
as well as the relative standing of the Deaf as compared with the Hearing can
be easily read off in the Table.
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