In regard to range of audible sensation, Mr. Galton, using his whistle at the Anthropometric Laboratory at South Kensington, found that 18 per cent males could hear the shrillest test-note as against only n per cent, females; and that 34 per cent males heard the next shrillest test-note as against 28 per cent of the females. This result harmonises with what we know of sight It is worthy of note that pianoforte tuners are usually ijien. I am not aware whether this is owing to the inability of women to rival men in this field.
SIGHT.
Blindness in this country (according to the census of 1 891) is much more common among males than among females at all ages up to 65; the preponder- ance of women after this age is due simply to the greater longevity of women. It does not seem to be true, however, that minor defects of sight are more common in men. The most convenient method of estimating the sexual distribution of defective eyesight is by referring to the data collected by ophthalmic surgeons. Thus Mr. R. Brudenell Carter has analysed his notes of 10,000 cases of disease or disturbance of the eyes in his own private practice, and finds 4621 males to 5379 females; this is over 600 more females than there would have been had his patients been in exact ratio to the general population. In classifying his cases according to the shape of the eyeball, he finds: — Google THE SENSES.
Males.
Females.
Total Emmetropia or normal eye-sight.
Short-sight or myopia, including^ simple and compound myopic 1 astigmatism (or irregularity of | eye-ball) J Long-sight or hypermetropian including simple and com-l pound hypermetropic astig-f matism J Mixed astigmatism 39 49 88 Totals Therefore among Mr. Carter's patients, belonging to the well-to-do classes, there has been, even when the sexual ratio in the general population is taken into account, a distinct preponderance of women and girls. The preponderance is not to be explained, Mr. Carter points out, by special proclivity on the part of women to any single form of eye-disease. He is " inclined to refer it to the greater sensitiveness of the female sex, to the more sedulous employment of their eyes over a variety of sedentary occupations, and to their weaker muscles, which are less able, as a rule, than those of men to maintain prolonged efforts of accommodation or of convergence." 1 Mr. Carter's cases are fairly chosen, and sufficiently large in number to be reliable. We may accept them as showing that vision is in all directions more frequently defective in women than in men.
A number of investigations have been made in schools in various countries, more especially in the United States, Germany, and Sweden, with the special object of determining the prevalence of eye- defect among school-children, and the more extensive 1 " An Analysis of Ten Thousand Cases of Disease or Disturbance of the Eyes, seen in Private Practice, " Lancet, Oct. 29, 1892.
Google 136 MAN AND WOMAN.
and reliable of these investigations show a preponder- ance of the short-sighted among girls which is much more marked than among Mr. Carter's patients. Thus among 11,000 boys in Sweden, Professor Axel Key has found that short-sightedness ranges from 6 per cent at the age of 11 to 37.3 per cent at the age of 19. But among 3000 Swedish girls he found that short-sightedness ranged from 21.4 per cent at the age of 10 to 50 per cent and over at the age of 20. 1 In America Dr. West examined the sight of 793 boys and 602 girls in the public schools of Worcester, Mass., using Snellen's test-types for the younger children, the Galton eye-test for those in the higher grades. In all the nine grades, except the first, which includes the youngest children, it was found that the percentage of defective eyes was distinctly greater among the girls, the difference usually being over 10 per cent; but among boys the defect seemed to be more serious in a larger number of cases. 2 >C Dr. F. Warner's observations, based on an examination of 60,000 school children, also showed that serious eye defects are more common in boys. 8 When we turn from the evidence furnished by investigations into the prevalence of eye-defect to more special investigations into the relative keenness of sight of men and women, the data at hand are found to be very limited. The examination at Bath of members of the British Association, by means of Galton's test, revealed little sexual difference; the men had rather better sight with the right eye, the women rather better sight with the left. At his Health Exhibition Laboratory Mr. Galton found that men are generally slightly superior to women in keenness of vision. Jacobs and Spielman found that the English Jewess is decidedly superior to the English Jew in keenness 1 Die Pubertatsentwickelung, etc, pp. 30, 61.
* American Journal of Psychology, August 1892, pp. 595-599.
T Brit. Mea. Journal, 25th March 1893.
Google THE SENSES. 137 of sight, both in the average and in the maximum and minimum; they are in this test above both the male and female as tested at the Health Exhibition by Galton. 1 Professor Jastrow has made some careful and interesting experiments on a small number of male and female students of Wisconsin University. 2 There were 31 men whose average age was 22 years, and 22 women whose average age was 21 years; the majority were born in Wisconsin, and three-fourths of their parents were of American birth, mostly mer- chants, professional men and farmers; nearly all the students were in good health, although some of them were troubled with headaches. The printed page was first placed beyond the subject's vision, then gradually moved towards him until he could just read it The distance at which the page could be read with maximum strain was found to be slightly greater in the men, but the difference was too slight to be of any significance; the nearest point at which the type could be read was also almost identical. The smallest type was then ascertained which was visible at 25 feet; this was found to be (in dioptrics) 94 for the men, 6.7 for the women. Acuteness of vision was tested in several ways: it was found that a series of lines 1 mm. wide and separated by spaces of I mm. could be distinctly discerned at a distance of 1 17 inches by the men, of 97 inches by the women; a simi- lar determination with a checkerboard pattern, both black and white squares being 4 mm. square, gave 121 inches for the men, 124 inches for the women; and it was found that irregularly arranged dots could also be counted at about the same distance by both men and women, although when the dots became rather numerous the men had a slight advantage. The strength of vision was tested by noting the smallest 1 " Comparative Anthropometry of English Jews," Journal Anih. Institute, August 1889.
2 " Studies, etc" Amer. Journal Psych. % April 1892.
Google I38 MAN AND WOMAN.
size of letter readable at 25 feet through one and through two thicknesses of common cheese-cloth; the result in dioptrics was, through one thickness, 24.7 for the men and 19.0 for the women; through two thicknesses 45.0 for the men, 42.0 for the women.
Taking the evidence as a whole, we may conclude that in most, if not all, civilised countries women are more liable to the slight disturbances of eye-sight, due to defective accommodation, which are peculiarly associated with civilisation; * while men are probably more liable to serious eye-defects. If, however, we take men and women belonging to the healthiest classes of the community and test the strength and acuteness of their vision, there is found to be no marked sexual difference.
Colour-perception and colour-blindness. — Newton was able to make out seven colours in the spectrum. Those who possess this power can see a dark blue band between blue and violet, and they also see a broader orange band than ordinary people; they are always very fond of colour. Green has only found three persons who saw the seven colours (and con- siders they are about 1 in 2000 or 3000 individuals); they were all males. 2 Professor Nichols has made some interesting experiments as to sexual differences in the sensitiveness of the eye to faint colour. 8 The pigments selected were red lead, chromate of lead, chromic oxide, and ultramarine blue. Each of these pigments was mixed in a carefully graduated way with white magnesium carbonate, so that a series of coloured powders was formed of which the pure pig- 1 Animals furnish a confirmation of the association of eye defects with civilised conditions. Motais, in a contribution to the Paris Academy of Medicine, stated that having examined the eyes of wild beasts, captured after they had reached adult age, he found them normal; those captured earlier, and still more those born in captivity, were short-sighted.
8 " On the Sensitiveness of the Eye to Colours of a Low Degree of Saturation," by E. L. Nichols, Ph.D., Ante ican Journal of Science % Google THE SENSES.
mcnt formed the first, while the succeeding number were of less and less saturated hue, and finally could not be distinguished from white. These were put into small glass phials. The four sets of bottles (labelled by means of marks) — thus containing mixtures of red and white, yellow and white, green and white, blue and white — were then mingled in- discriminately, and the observer was requested to arrange them according to hue and degree of colour- saturation. The individuals examined were 54 in number (31 males and 23 females), mostly between the ages of fifteen and thirty. Five were more or less colour-blind, but this defect was not found to injure in a marked way their ability to classify the colours. In the following table the figures indicate the amount of colouring matter present in ipo,ooo,ooq volumes of white in the most dilute mixture which can be distinguished from a pure white by the average observer: — Average for males 15.9 „ „ females! 59.8 Bed Lead.
Chromate of Lead.
Chromic Oxide.
Ultramarine.
" As will be seen from the above table the average male observer is measurably more sensitive to red, yellow, and green, while the female shows superiority in the blue alone." The light reflected by pigments, as Professor Nichols points out, is not monochro- matic, so that these results cannot be held to show us accurately the relation of the eye to the pure spectrum.
The individual variations were very great: 8 persons (5 males and 3 females) could distinguish yellow in a mixture of 3 parts in 100,000,000; while 2 (both females) could only detect it in a mixture containing 190 parts to 100,000,000. The lack of delicacy with respect to green was a general trait, possibly, remarks Professor N ichols, traceable to familiarity with foliage.
In arranging the phials in order in the series, women on the Google 140 MAN AND WOMAN.
average were superior to men, though the two nearest approaches to complete accuracy were both men. In the following table ico would indicate complete accuracy: — Bed Lead.
Chromate of Lead.
Chromic Oxide.
Ultramarine.
Male...Female.
It would be interesting to consider whether special delicacy in discrimination of a colour is accompanied by special prefer- ence for that colour, or the reverse, but there is no evidence at present to decide this. Professor Earl Barnes found in Cali- fornia, among nearly 1000 children of all grades, that while the favourite colours of boys and girls were essentially the same, more girls select red, more boys blue. " If," he remarks, " with increasing years children generally select more red and less blue, as seems to be the case, this would indicate that girls are more mature than boys on an average" {Pedagogical Seminary ', March 1893).
These observations, so far as they go, tend to show, as also the observations on eye-sight also seem to show, that in range of sensation women are inferior to men, but that within the limits of ordinary range common to both sexes women have perhaps slightly greater power of discrimination.
When we turn to the sexual difference in regard to colour-blindness, a subject which has been very fully investigated, there is no doubt whatever about the results. Men are much more frequently colour- blind than women. The committee on colour- blindness of the Ophthalmological Society found that among males generally (z.&, out of 14,846 individuals) the percentage of pronounced cases of colour-blindness was 3.5, the average percentage being 4.16. They found that colour-blindness was nearly always much slighter in females than in males, and even then only existed in 0.4 per cent. 1 Holmgren, from an examination of 32,000 men, 1 " Report of the Committee on Colour-Blindness of the Ophthal- mological Society," Trans. OphthaL Soc, 1881.
Google THE SENSES. 141 found 3.17 per cent colour-blind. Dr. Joy Jefferies of Boston, from an examination carried on chiefly in educational institutions, of over 18,000 males, found 4.1 per cent colour-blind, and among over 14,000 females only 0.008 were colour-blind. Mr. T. H. Bickerton finds the percentage 0.16. Therefore while colour- blindness exists in about 30 to 40 per thousand males of the general population of European countries it is found in only 1 to 4 per thousand females, being thus at least ten times more frequent in men than in women. One woman to ten men is the proportion found by Favre in France. 1 There are certain variations in the incidence of colour-blindness, among classes of the population and among races, which are of interest, and may possibly bear on the significance of colour-blindness. Among the professional classes (medical students, etc.) the Ophthalmological Society's Committee found the proportion to be 2.5 per cent; among Eton boys 2.46 per cent; among the boys and masters at Marlborough School (according to the Anthropo- logical Committee of the British Association) it is 2.5 per cent On the other hand, among the police and in schools of the same social rank the Ophthal- mological Society's Committee found pronounced cases in the proportion of 3.7 per cent, and in middle-class schools 3.5. In Ireland the sons of labourers are twice as liable to colour-blindness as the boys of the wealthier classes. A comparison of urban and rural populations, so far as it shows anything, points to colour-blindness being more common in the country. Jews and Quakers are more subject to colour-blindness than the ordinary population. Among (730) females of Jewish extrac- tion, 3.1 per cent were affected; among females belonging to the Society of Friends, 5.5; they were, however, slight cases. It was the same among the 1 Communication to the Academie des Sciences in 1878.
Google 142 MAN AND WOMAN.
males; among 949 of Jewish extraction 4.9 were affected; among (491) Quakers, 5.9. It must be noted that the Jews were on the whole of poorer condition of life than the average, and their defects were of pronounced character; the Friends belonged to the middle class, and their defects, chiefly confined to the paler shades, were slight; the wealthy Friends were less colour-blind than the poor, though still, among males, exceeding the average. 1 Jacobs and Spielman found no fewer than 12.7 per cent, of London Jews to be colour-blind; it must be added that while in the East End the proportion was as high as 14.8 per cent, in the West End it was only 3.4 per cent.; these observers associate this tendency to colour-blindness with the absence of great painters among the Jews and the bad taste in dress shown by Jewesses belonging to the lower social grades. 2 It is necessary to take a somewhat wider survey in order to appreciate the significance of colour- blindness. Although among civilised races colour- blindness is more prevalent in the lower than in the higher social classes, among barbarous and savage races it is very infrequent One of the earliest investigators of colour-blindness, Professor George Wilson, examined several foreign students in England — Chinese, Kaffir, etc.: " their apprecia- tion of colour," he remarks, "is excellent, and certainly superior to that of the majority of our own students, who have not accidentally or designedly made colour a special object of study. The most expert of them all was the young Caffre." 8 Later and more extended investigation has shown very clearly the freedom of lower races from colour- blindness as well as their delicacy of colour-percep- tion. Schellong among the Papuans of the New 1 " Report of the Committee on Colour- Blindness of the Ophthal- mological Society. " 8 Journal Anthrop. Institute, Aug. 1889.
8 Researches on Colour-Blindness, Edinburgh, 1855, p. yy.
Google THE SENSES. 143 Hebrides found that the colour-sense is highly developed; they are able without hesitation to distinguish even delicate shades of difference, although their colour vocabulary is extremely limited, and they only possess one word for green and blue. 1 Among 1200 Japanese soldiers 3.4 per cent, were colour-blind. An examination of 600 Chinese men and 600 Chinese women showed that 19 men (or 3.2 per cent) and only 1 woman (or.17 per cent.) were colour-blind. 2 Favre among Algerian tribes found only 2.6 per cent, colour- blind. Dr. L. Webster Fox, in a lecture delivered before the Franklin Institute, Philadelphia, stated that in an examination of 250 Indian children, of whom 100 were boys, he did not find a single case of colour-blindness; on a previous occasion he had examined 250 Indian boys and only found 2, or less than 1 per cent, colour-blind; he finds the proportion among white boys of the United States to be at least 5 per cent Blake and Franklin of Kansas University also examined Indians, and found that among 285 males there were only three cases of colour-blindness, or scarcely more than 1 per cent, while among 133 females none were found to be colour-blind. 8 In Chili colour-blindness is decidedly rarer than in northern Europe. In a graduation thesis on colour-blindness at the University of Santiago, Senor Conrado Rios states that he has examined 1200 male persons, including 520 boys of from five to fifteen years of age, with the result that 3 per cent, of the boys and 2.1 per cent, of the men presented more or less colour- blindness. He also examined 320 females, including 143 girls of from five to fifteen years of age. One girl could not distin- guish between blue and violet, and a few confounded faint shades of green with yellow. Some other girls also showed a little hesitation in picking out certain colours, but none of the adult women presented any want of appreciation of colours at 1 "Beitrage zur Anthropologic der Papuas," Zeitschrift fur Anth. t 8 Science, 14th Nov. 1890. 8 Science, 2nd June 1893.
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all. When an examination was made some years ago by a Swedish commission of 500 naval cadets and other persons in Chili, only one or two cases of colour-blindness were found. (Lancet> August 1890.) Dr. Rios attributes this slighter preva- lence of colour-blindness in Chili to the frequency of alcoholism in Europe; it is probable, however, that a native Indian element in the population of Chili has also to be reckoned with.
Colour-blindness is clearly not a result of disease, nor is it associated with diseased conditions. It is true that it is rather more common among deaf-mutes than among the average of the population, but the deaf-mutes examined have largely belonged to the low social class in which colour-blindness has been found most prevalent. Among imbeciles colour- blindness is rare. Among criminals also it has not usually been found common. Among cretins the colour sense is usually present, although speech, hearing, and smell are nearly always very defective. 1 And, on the other hand, Jews, among whom colour- blindness is specially prevalent, are a healthy class of the population (except for their tendency to nervous disease), and show a very high average of ability; and the Quakers also are a distinguished class of the community.
The precise significance of the sexual difference regarding colour-blindness cannot yet be determined. The whole question of colour-blindness and of the mechanism of colour-vision generally is still under discussion. But there can be little doubt now that the greater liability of males to colour-blindness is inherent and of world-wide extension. Train- ing has little to do with it; and comparisons between children under ten years of age and adults (in the hands of the Ophthalmological Society's Committee) have shown few differences. On the other hand, its hereditary nature is well recognised; it is sufficient to mention one case: Dr. Pliny Earle, 1 Professor Horsley, Art. " Cretinism " in Hack Tuke's Dictionary of Psychological Medicine, 1 892.
Google THE SENSES. 145 Professor Wilson tells us, out of 32 male and 29 female relations had 20 who were colour-blind, only two, however, being female. The undoubted fact that women are more familiar with the names of colours has been considered a source of fallacy, but modern methods of examination do not require any acquaintance with names. The greater familiarity of women with dress has been considered to account for the difference; the colour-blindness of Quakers, who are usually considered as indifferent to dress and favouring sombre hues, might be brought forward to support this theory. But it can scarcely be used to explain the very marked sexual difference among lower races; and it may be quite as reasonably argued that the Society of Friends found a specially large number of recruits among individuals indifferent to colour and defective in perceiving it It is somewhat curious that such scanty evidence as I have been able to gather concerning keenness of colour-perception does not seem to agree with the very clear evidence concerning colour-blindness. It is noteworthy that in Professor Nichols' experiments — though these were not on a decisive number of persons — the colours in regard to which the men were especially more sensitive than the women were red and green, precisely the colours that are defectively seen in colour-blindness. And Mr. Green found that exceptional range of colour-perception occurred ex- clusively in males. It would seem that we are dealing with two different classes of phenomena. Colour-blindness is a defect comparable to albinism and to the other congenital abnormalities that are more common in males. It has nothing to do with keenness in sensory discrimination, and it is prob- able that, as seems to be true in regard to some other sense perceptions, there is greater range and acuteness of colour-perception in men.
10 Google I46 MAN AND WOMAN.
COLOURED HEARING.
This is one of the names for the best known of a large group of slightly abnormal psychic phenomena. A person is the subject of coloured hearing when a particular sound immediately and involuntarily brings a particular colour to the mental eye. Usually each of the vowel sounds has a colour of its own, and • words are coloured accordingly. Besides coloured hearing we may have other automatic sense- associations, such as coloured gustation, coloured olfaction, coloured tactility, coloured motility. 1 Mr. Francis Galton many years ago investigated various of these associations. He seems to have found colour association more common in women than in men; he also found that it " appears to be rather common, though in an ill-developed degree, among children." 2 The allied phenomenon of the " number-form " (" the sudden and automatic appear- ance of a vivid and invariable form in the mental field of view, whenever a numeral is thought of, and in which each numeral has its own definite place") was also found by Galton to be more common in women; speaking roughly, it exists in 1 out of 30 males, and in 1 out of 15 females. Number-forms originate at an early age, and are commoner in young persons than in adults. 8 Fechner collected 73 cases* 1 See Art. ''Secondary Sensations," by Bleeler, in Tuke's Diet, of Psych. Med.; Grttber's "V Audition Colored et les Phenomenes similaires" in Proceedings of the International Congress of Experimental Psychology, London, 1892; and Krohn's " Pseudo-Chromaesthesia " in American Journal of Psychology, October 1892. The last contains a full bibliography.
2 Inquiries into Human Faculty, p. 147.
8 Ibid., p. 119, Galton remarks that the somewhat allied power of visualising — or of unconsciously storing up in the mind mental pictures which may be voluntarily recalled — " is higher in the female sex than in the male, and is somewhat, but not much higher in public school- boys than in men...There is reason to believe that it is very high in some young children, who seem to spend years of difficulty in distinguishing between the subjective and objective world. Language and book-learning certainly tend to dull it. (P. 99.) The men of Google THE SENSES. 147 of coloured hearing, 35 of men, 38 of women; they were nearly all adults and of the educated classes. 1 Krohn found that coloured hearing and similar phenomena are more common in women than in men. Recent investigation at Wellesley College, an American women's college, of 543 persons, showed that nearly 6 per cent possessed the faculty of coloured hearing, while about 18 per cent showed either coloured hearing or number-forms, or both combined. This is certainly a high proportion, although I do not know of any similar investigation at a men's college with which to compare it. The results were verified and confirmed by questioning the subjects after an interval of two months. 2 Large, however, as this percentage is, it is greatly exceeded by the results of a subsequent investigation at the same college on the students who entered in the autumn of 1892; out of 203 persons not less than 32, or 15.7 per cent, were colour-hearers, while 61, or 30.2 per cent, had " forms," and 17, or 8.4 per cent, showed both psychic abnormalities. 8 It may be asserted with little fear of contradiction that all investigators who have given attention to the point have found coloured hearing and allied pheno- mena more common in women than in men.
I have presented with some fulness such evidence as I have been able to obtain regarding sexual differ- ences in acutenessand precision of sensory perceptions, science he spoke to knew nothing of it. " On the other hand...many men, and a yet larger number of women, and many boys and girls, declared that they habitually saw mental imagery, and that it was perfectly distinct to them, and full of colour." Cross-examination brought out the evident truth of these assertions. (P. 85.)
1 Fechner, Vorschule der Aesthetik, Zweiter Theil, p. 316.
1 Mary Whiton Calkins, " Experimental Psychology at Wellesley College," American Journal of Psychology ', vol. v., No. 2 (November * Mary W. Calkins, "A Statistical Study of Pseudo-Chromesthesia and of Mental Forms," American Journal Psychology^ July 1893. This is an interesting and carefully detailed study.
Google I48 MAN AND WOMAN.
notwithstanding the fact that that evidence does not point emphatically to the general and absolute superiority of either sex. The one very decided exception is in regard to colour-blindness, and this, probably, is simply a case of the greater varia- tional tendency of males. Notwithstanding this the results so far reached have a certain interest It has always been the popular notion that women have keener and more delicate sensory perceptions than men; this opinion has even been repeated by numerous men of science who have not themselves made any investigation of the actual facts. We have seen that there is little reason to suppose that women have more delicate senses, and considerable reason to suppose that most of their senses are somewhat less keen, a result which was long since stated by Burdach, 1 and which is in harmony with what we know of the sense-organs of animals generally; the antennas of insects, the hairs, eyes, are nearly always more developed in the male. At the least, it can only be said that the senses of men and women are possibly equal, but that those of women are habitually subject to a less thorough education, and therefore often re- main in a somewhat more rudimentary state. I have brought together a considerable amount of evidence tending in this direction: the greater gustatory acute- ness even of town-dwelling thieves over normal country- dwelling persons, the comparative sexual equality from the sensory point of view of pupils in American co-educational colleges, the notable increase of tactile sensation in a lower race after education in Europe, and the great rapidity with which an increased keen- ness of tactile sensibility can be obtained through practice.
There is some interest in considering how women have obtained their reputation for delicate sensory perceptions. On this point there can, I think, be little doubt It is due to a popular confusion of two Google THE SENSES. 1 49