Scientific American Supplement, No. 358, November 11, 1882

V >> Various >> Scientific American Supplement, No. 358, November 11, 1882

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Dr. Tyndall showed that where there is quiescence in the air the
tendency of his sterilized infusions to produce organisms was increased.
The conclusion from all these experiments is to show the importance of
laying out the general plan of dwellings in a town so that currents of
air shall be able to flow on all sides with as little impediment as
possible, by which means the air will be continually liable to renewal
by purer air. The dwellings which have been constructed in the place of
the very defective dwellings condemned by the medical officers of health
in various parts of London specially illustrate the importance of this
question of the circulation of air. These dwellings replace those in
which the normal mortality was as much as 33, 44, and 50 per 1,000. But
these improved dwellings provide ample space all round the blocks
of building, so that air can flow round and through them in every
direction, and so that there are no narrow courts and hidden corners for
the accumulation of refuse. The mortality in the new dwellings is as low
as 13 per 1,000 in some, and does not rise above 20 per 1,000 in any of
them, and upon an average of years it may be taken at from 14 to 16
per 1,000. It is to this point that I specially desire to draw
attention--namely, that these facts prove the possibility of bringing
down the death-rate of the class of population which inhabits this sort
of accommodation to rates varying from 15 to 16 per 1,000. I say of the
class of population, because habits and mode of life have an important
influence on health and on longevity.

Mr. Chadwick and Dr. Richardson obtained some statistics for
Westminster, for the use of a committee of the Society of Arts, which
indicate the very different conditions of health to which the different
classes of population are subject. It appeared from these statistics
that out of one hundred deaths of the first class, or gentry, six were
those of children in their first year, and nine of children within
their fifth year; while out of one hundred deaths of the wage classes
twenty-two are those of children in their first year, and thirty-nine
within their fifth year. If we take the average duration of life of all
who have died of the first class, men, women, and children, we find that
they have had an average of fifty-five years and eight months of life;
while of the wage classes they have had a mean of only twenty-eight
years and nine months. And if we take the average duration of life of
those who have escaped the earlier ravages of death up to twenty years
of age, the males who have died of the first class have had sixty-one
years of life, while of the wage class the males have had only
forty-seven years and seven months. Moreover, of the first class in
Westminster, the proportion who have attained the old age, and died
of natural causes, is 3.27 per cent., but of the wage classes only a
fraction, or two-thirds per cent., did so. I have obtained similar
returns for this town. It was considered desirable, for the purpose of
this return, to divide the population into the following five classes:
First, gentry and professional men; second, tradesmen and shopkeepers;
third, shipwrights, chain and anchor smiths, iron forge laborers, etc.,
fourth, seamen, watermen, fishermen, etc.; fifth, other wage clashes
and artisans; and each of these classes represents distinct sanitary
conditions and habits of life. The healthiest class is that of the
seamen, watermen, and fishermen. The mean age at death of all who died
of that class, men, women, and children, is thirty-seven years, as
compared with thirty five years for gentry and professional men; while
the mean age of shipwrights, chain and anchor makers, and iron forge
laborers is only twenty-two years. The President considered that these
points gave much food for reflection. He then touched upon the important
question of the effect of occupation upon health, and remarked: If we
take the professional and merchant class, who attend at their offices
during the daytime, we may be sure that, as a rule, they are placed
in unhealthy surroundings during that time, and in many cases have to
breathe during their hours of work as bad an atmosphere as that in which
the wage classes work. He also quoted returns showing that the great
mortality among the tradesmen class in Westminster was explained from
the fact that the best rooms in the houses in which they live were let
for lodgings, the tradesmen contenting themselves with living in the
basements or back premises, which were frequently unhealthy. He looked
for great improvements in the health of the wage classes by the
construction of improved dwellings; but, he confessed, in many cases
workmen required to be taught to attend to precautions devised for their
health.

On the subject of sickness caused by insanitary conditions, he quoted
the remark of an East London clergyman that the "poor go on living in
wretched places, but have much ill-health." He showed from Mr. Burdett's
figures that the London voluntary hospitals and dispensaries cost nearly
L600,000 a year to administer--an expenditure incurred mainly for the
purpose of "patching up" the wretched poor who had been injured by bad
drainage, want of ventilation and the like; and he urged that it might
be safely assumed preventive measures would bring down the death-rate of
the wage class to one-half, reducing also the sickness rate in at least
a similar proportion. By means of this item alone the wage-earning power
of the industrious classes would be enlarged by some millions of pounds,
and their comfort correspondingly increased. There would also, he
contended, be other distinct economies, for there would be less need for
much of the accommodation in prisons, reformatories, and workhouses
now needed from evils incident to unhealthy circumstances and crowded
dwellings.

He dwelt upon the economic advantages of sanitary measures generally,
dealing first with the subject of the conversion of sewage into manure,
and then, in relation to the provision of healthful dwellings, such as
those of the Metropolitan Association for Improving the Dwellings of the
Industrial Classes, he showed that the cost of such dwellings had been
about L1,900,000 for 11,000 persons. By the saving in life and health,
through the continuance in earning power of men, whose lives would
otherwise have been cut short, he estimated that the expenditure of the
L1,900,000 for the 11,000 persons, by the addition often years' earning
power to the heads of families, brought in a return of L4,600,000, and
urged these facts as showing the pecuniary advantages accruing to the
nation from sanitary improvements which led to decreased death and
sickness rates. On the one hand, he said, insanitary dwellings and
insanitary conditions of life engendered sickness, entailed poverty, and
fostered crime, while improved dwellings insured improved health, and by
affording a security for the more continuous earning of wages created
the possibility of a comfortable home. Advanced sanitarians had long
preached these doctrines, and he was happy to think that they were at
last beginning to hear some results, and in those results he saw the
means of developing morality, contentment, and happiness among the
people.

* * * * *

[NATURE.]

PSYCHOLOGICAL DEVELOPMENT IN CHILDREN.

[Footnote: _Die Seele des Kindes Beobachtungen ueber die geistige
Entwickelung des Menschen in den ersten Lebensjahren_. Von W. Preyer,
ordentlichen Professor der Physiologie an der Universitaet und Director
des physiologischen Instituts zu Jena, etc. Leipzig: Th. Grieben. 1882.]

This is a large octavo volume, extending to over four hundred pages,
and consisting of daily observations without intermission of the
psychological development of the author's son from the time of birth
to the end of the first year, and of subsequent observations less
continuous up to the age of three years. Professor Preyer's name is a
sufficient guarantee of the closeness and accuracy of any series of
observations undertaken with so much earnestness and labor, but still
we may remark at the outset that any anticipation which; the reader may
form on this point will be more than justified by his perusal of this
book. We shall proceed to give a sketch of the results which strike
us as most important, although we cannot pretend to render within the
limits of a few columns any adequate epitome of so large a body of facts
and deductions.

The work is divided into three parts, of which the first deals with the
development of the senses, the second with the development of the will,
and the third with the development of the understanding.

Beginning with the sense of sight, the observations show that light is
perceived within five minutes after birth, and that the pupils react
within the first hour. On the second day the eyes are closed upon the
approach of a flame; on the eleventh the child seemed to enjoy the
sensation of light; and on the twenty-third to appreciate the rose color
of a curtain by smiling at it. Definite proof of color discrimination
was first obtained in the eighty-fifth week, but may, of course, have
been present earlier. When seven hundred and seventy days old the child
could point to the colors yellow, red, green, and blue, upon these being
named.

The eyelids are first closed to protect the eyes from the sudden
approach of a threatening body in the seventh or eighth week, although,
as already observed, they will close against a strong light as early as
the second day. The explanation of their beginning to close against the
approach of a threatening body is supposed to be that an uncomfortable
sensation is produced by the sudden and unexpected appearance, which
causes the lids to close without the child having any idea of danger to
its eyes; and the effect is not produced earlier in life because the
eyes do not then see sufficiently well. On the twenty-fifth day the
child first definitely noticed its father's face; when he nodded or
spoke in a deep voice, the child blinked. This Professor Preyer calls a
"surprise-reflex;" but definite astonishment (at the rapid opening and
closing of a fan) was not observed till the seventh month. The gaze was
first fixed on a stationary light on the sixth day, and the head
was first moved after a moving light on the eleventh day; on the
twenty-third day the eyeballs were first moved after a moving object
without rotation of the head; and on the eighty-first day objects were
first sought by the eyes. Up to this date the motion of the moving
object must be slow if it is to be followed by the eyes, but on the
one hundred and first day a pendulum swinging forty times a minute
was followed. In the thirty-first week the child looked after fallen
objects, and in the forty-seventh purposely threw objects down and
looked after them. Knowledge of weight appeared to be attained in
the forty-third week. Persons were first distinguished as friends
or strangers in the sixth month, photographs of persons were first
recognized in the one hundred and eighth week, and all glass bottles
were classified as belonging to the same genus as the feeding-bottle in
the eighth month.

With regard to the sense of hearing, it is first remarked that all
children for some time after birth are completely deaf, and it was not
till the middle of the fourth day that Professor Preyer obtained any
evidence of hearing in his child. This child first turned his head in
the direction of a sound in the eleventh week, and this movement in the
sixteenth week had become as rapid and certain as a reflex. At eight
months, or a year before its first attempts at speaking, the infant
distinguished between a tone and a noise, as shown by its pleasure on
hearing the sounds of a piano; after the first year the child found
satisfaction in itself striking the piano. In the twenty-first month
it danced to music, and in the twenty fourth imitated song; but it is
stated on the authority of other observers that some children have
been able to sing pitch correctly, and even a melody, as early as nine
months. One such child used at this age to sing in its sleep, and at
nineteen months could beat time correctly with its hand while singing an
air.

Concerning touch, taste, and smell, there is not so much to quote,
though it appears that at birth the sense of taste is best developed,
and that the infant then recognizes the difference between sweet, salt,
sour, and bitter. Likewise, passing over a number of observations on the
feelings of hunger, thirst, satisfaction, etc., we come to the
emotions. Fear was first shown in the fourteenth week; the child had an
instinctive dread of thunder, and later on of cats and dogs, of falling
from a height, etc. The date at which affection and sympathy first
showed themselves does not appear to have been noted, though at
twenty-seven months the child cried on seeing some paper figures of men
being cut with a pair of scissors.

In the second part of the book it is remarked that voluntary movements
are preceded, not only by reflex, but also by "impulsive movements," the
ceaseless activity of young infants being due to purposeless discharges
of nervous energy. Reflex movements are followed by instinctive, and
these by voluntary. The latter are first shown by grasping at objects,
which took place in Preyer's child during the nineteenth week. The
opposition of the thumb to the fingers, which in the ape is acquired
during the first week, is very slowly acquired in the child, while, of
course, the opposition of the great toe is never acquired at all;
in Preyer's child the thumb was first opposed to the fingers on
the eighty-fourth day. Up to the seventeenth month there is great
uncertainty in finding the mouth with anything held in the hand--a
spoon, for instance, striking the cheeks, chin, or nose, instead of at
once going between the lips; this forms a striking contrast to the case
of young chickens which are able to peck grains, etc., soon after they
are hatched. Sucking is not a pure reflex, because a satisfied child
will not suck when its lips are properly stimulated, and further, the
action may be originated centrally, as in a sleeping suckling. At a
later stage biting is as instinctive as sucking, and was first observed
to occur in the seventeenth week with the toothless gums. Later than
biting, but still before the teeth are cut, chewing becomes instinctive,
and also licking. Between the tenth and the sixteenth week the head
becomes completely balanced, the efforts in this direction being
voluntary and determined by the greater comfort of holding the head in
an upright position. Sitting up usually begins about the fourth month,
but may begin much later. In this connection an interesting remark
of Dr. Lauder Brunton is alluded to ("Bible and Science," page 239),
namely, that when a young child sits upon the floor the soles of his
feet are turned inward facing one another, as is the case with monkeys.
When laid upon their faces children at earliest can right themselves
during the fifth month. Preyer's child first attempted to stand in the
thirty-ninth week, but it was not until the beginning of the second year
that it could stand alone, or without assistance. The walking movements
which are performed by a child much too young to walk, when it is
held so that its feet touch the ground, are classified by Preyer as
instinctive. The time at which walking proper begins varies much with
different children, the limits being from eight to sixteen months. When
a child which is beginning to walk falls, it throws its arms forward to
break the fall; this action must be instinctive. In the twenty-fourth
month Preyer's child began spontaneously to dance to music and to beat
time correctly.

A chapter is devoted to imitative movements. At the end of the fifteenth
week the child would imitate the movement of protruding the lips, at
nine months would cry on hearing other children do so, and at twelve
months used to perform in its sleep imitative movements which had made a
strong impression while awake--e.g., blowing; this shows that dreaming
occurs at least as early as the first year. After the first year
imitative movements are more readily learned than before.

Shaking the head as a sign of negation was found by Preyer, as by other
observers, to be instinctive, and he adopts Darwin's explanation of the
fact--viz., that the satisfied suckling in refusing the breast must
needs move its head from side to side. In the seventeenth month the
child exhibited a definite act of intelligent adjustment, for, desiring
to reach a toy down from a press, it drew a traveling-bag from another
part of the room to stand upon. We mention this incident because it
exhibits the same level of mental development as that of Cuvier's orang,
which, on desiring to reach an object off a high shelf, drew a chair
below the shelf to stand upon. Anger was expressed in the tenth month,
shame and pride in the nineteenth.

Between the tenth and eleventh month the first perception of causality
was observed. Thus on the three hundred and nineteenth day the child was
beating on a plate with a spoon and accidentally found that the sound
was damped by placing the other hand upon the plate; it then changed its
hands and repeated the experiment. Similarly at eleven months it struck
a spoon upon a newspaper, and changed hands to see if this would modify
the sound. In some children, however, the perception of causality to
this extent occurs earlier. The present writer has seen a boy when
exactly eight months old deriving much pleasure from striking the
keys of a piano, and clearly showing that he understood the action of
striking the keys to be the antecedent required for the production of
the sound.

The third part of the book is concerned, as already stated, with the
development of the understanding. Here it is noticed that memory and
recognition of the mother's voice occurs as early as the second month;
at four months the child cried for his absent nurse; and at eighteen
months he knew if one of ten toy animals were removed. In Preyer's
opinion--and we think there can be no question of its accuracy--the
intelligence of a child before it can speak a word is in advance of that
of the most intelligent animal. He gives numerous examples to prove that
a high level of reason is attained by infants shortly before they begin
to speak, and therefore that the doctrine which ascribes all thought to
language is erroneous.

Highly elaborate observations were made on the development of speech,
the date at which every new articulate sound was made being recorded.
The following appear to us the results under this head which are most
worth quoting.

Instinctive articulation without meaning may occur as early as the
seventh week, but usually not till the end of the first half year. Tones
are understood before words, and vowel sounds before consonants, so
that if the vowel sounds alone are given of a word which the child
understands (thirteen months), it will understand as well as if the word
were fully spoken. Many children before they are six months old will
repeat words parrot-like by mere imitation, without attaching to them
any meaning. But this "echo-speaking" never takes place before the first
understanding of certain other words is shown--never, e.g., earlier than
the fourth month. Again, all children which hear but do not yet speak,
thus repeat many words without understanding them, and conversely,
understand many words without being able to repeat them. Such facts
lead Professor Preyer to suggest a somewhat elaborate _schema_ of
the mechanism of speech, both on its physiological and psychological
aspects; but this _schema_ we have not sufficient space to reproduce.

Although the formation of ideas is not at first, or even for a
considerable time, dependent on speech (any more than it is in the case
of the lower animals), it constitutes the condition to the learning of
speech, and afterward speech reacts upon the development of ideation. A
child may and usually does imitate the sounds of animals as names of the
animals which make them long before it can speak one word, and, so far
as Preyer's evidence goes, interjections are all originally imitative
of sounds. Children with a still very small vocabulary use words
metaphorically, as "tooth-heaven" to signify the upper gums, and it is
a mistake to suppose that the first words in a child's vocabulary are
invariably noun-substantives, as distinguished from adjectives or even
verbs. As this statement is at variance with almost universal opinion,
we think it is desirable to furnish the following corroboration. The
present writer has notes of a child which possessed a vocabulary of
only a dozen words or so. The only properly English words were "poor,"
"dirty," and "cook," and of these the two adjectives, no less than the
noun-substantive, were always appropriately used. The remaining words
were nursery words, and of these "ta-ta" was used as a verb meaning to
go, to go out, to go away, etc., inclusive of all possible moods and
tenses. Thus, for instance, on one occasion, when the child was wheeling
about her doll in her own perambulator, the writer stole away the doll
without her perceiving the theft. When she thought that the doll had had
a sufficiently long ride, she walked round the perambulator to take
it out. Not finding the doll where she had left it she was greatly
perplexed, and then began to say many times "poor Na-na, poor Na-na,"
"Na-na ta-ta, Na-na ta-ta;" this clearly meant--poor Na-na has
disappeared. And many other examples might be given of this child
similarly using her small stock of adjectives and verbs correctly.

According to Preyer, from the first week to the fifth month the only
vowel sounds used are _ue_ and _a_. On the forty-third day he heard the
first consonant, which was _m_, and also the vowel _o_. Next day
the child said _ta hu_, on the forty-sixth day _goe oeroe_, and on the
fifty-first _arra_ All the vowel sounds were acquired in the fifth
month. We have no space to go further into the successive dates at which
the remaining consonants were acquired. In the eleventh month the child
first _learnt_ to articulate a certain word (_ada_) by imitation, and
afterward repeated the taught word spontaneously. The first year passed
without any other indication of a connection between articulation and
ideation than was supplied by the child using a string of different
syllables (and not merely a repetition of the same one) on perceiving a
rapid movement, as any one hurriedly leaving the room, etc.; but this
child nevertheless understood certain words (such as "handchen geben")
when only fifty-two weeks old. Inefficient attempts at imitative
speaking precede the accurate attempts, and at fourteen months this
inefficiency was still very apparent, being in marked contrast with the
precision whereby it would imitate syllables which it could already
say; the _will_ to imitate all syllables was present, though not the
_ability_. At the beginning of the fourteenth month on being asked: "Wo
ist dein Schrank?" the child would turn its head in the direction of the
cupboard, draw the person who asked the question toward it (though the
child could not then walk); and so with other objects the names of which
it knew. During the next month the child would point to the object when
the question was asked, and also cough, blow, or stamp on being told to
do so. In the seventeenth month there was a considerable advance in the
use of sign-language (such as bringing a hat to the nurse as a request
to go out), but still no words were spoken save _ma-ma, pa-pa_, etc. In
the twentieth month the child could first repeat words of two unlike
syllables. When twenty-three months old the first evidence of judgment
was given; the child having drunk milk which was too hot for it, said
the word "heiss." In the sixty-third week this word had been learnt in
imitative speaking, so it required eight and a half months for it to be
properly used as a predicate. At the same age on being asked, "Where is
your beard?" the child would place its hand on its chin and move its
thumb and fingers as if drawing hair through them, or as it was in the
habit of doing if it touched its father's beard; this is evidence of
imagination, which, however, certainly occurs much earlier in life. At
the close of the second year a great advance was made in using two words
together as a sentence--e.g., "home, milk," to signify a desire to go
home and have some milk. In the first month of the third year sentences
of three or even four words were used, as "papa, pear, plate, please."
Hitherto the same word would often be employed to express several or
many associated meanings, and no words appeared to have been entirely
invented. The powers of association and inference were well developed.
For instance, the child received many presents on its birthday, and
being pleased said "bursta" (=Geburtstage); afterward when similarly
pleased it would say the same word. Again, when it injured its hand it
was told to blow upon it, and on afterward knocking its head it blew
into the air. At this age also the power of making propositions advanced
considerably, as was shown, for instance, by the following sentence on
seeing milk spilt upon the floor: "Mime atta teppa papa oi," which was
equivalent to "Milch fort (auf den) Teppich, Papa (sagte) pfui!" But
it is interesting that at this age words were learnt with an erroneous
apprehension of their meaning; this was particularly the case with
pronouns--"dein Bett," for example, being supposed to mean "das grosse
Bett." All words which were spontaneously acquired seemed to be
instances of onomatopoeia. Adverbs were first used in the twenty-seventh
month, and now also words which had previously been used to express
a variety of associated or generic meanings, were discarded for more
specific ones. In the twenty-eighth month prepositions were first used,
and questions were first asked. In the twenty-ninth month the chief
advance was in naming self with a pronoun, as in "give me bread;" but
the word "I" was not yet spoken. When asked: "Wer ist mir?" the child
would say its own name. Although the child had long been able to say its
numerals, it was only in this month that it attained to an understanding
of their use in counting. In the thirty-second month the word "I" was
acquired, but still the child seemed to prefer speaking of itself in the
third person.

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