Son Son is doubtless owing in part to the small number of cases of some types of vision-6/12 and what we have called the "rest" being based on from 25 to 40 cases only. There is a similarity between these curves in some respects; we find that in all four the normal eyesight is above the mean, i.e. is getting into the "drinking" class of parents, and that eyesight measured by 6/9 in all four cases dips down into the sober class of parents; except in the case of mother and son eyesight of 6/12 is getting back into the drinking class and 6/18 dips again into the sober. In father and daughter the worst type of vision is found to be still further in the sober class, but for father and son and mother and daughter the worst type of vision is found comparatively high up among drinking parents. It is extremely difficult to say that there is any general slope of the means; and there is no definite conclusion which can be legitimately drawn beyond the assertion that if acuity of vision is related to parental alcoholism, the relation must be very slight and complex in character. If we simply divide the eyes into the two classes normal and abnormal the correlations if they are to be considered significant at all are negative, or again drinking in the parents is associated with normal vision in the offspring. (8) Parental Alcoholism and Eye Disease. Diseases of the eye and eyelid were relatively few in number and no division of them into categories was statistically possible. The original tables are given as XLI to XLIV in the Appendix. Cases of strabismus presented a difficulty as these are very few, but we decided to keep them separate and work out the table as a ninefold contingency. Drinking of the father and non-drinking of the mother are associated with normal eyes in son and daughter, and if we omit squint we shall find that the correlation between drink and eye disease is negative for the fathers and positive for the mothers. This difference may be just that due to the neglect that arises from the existence of an alcoholic mother. But the values are very small and we think we may say that no correlation between intemperance of the parent and eye disease in the child is indicated by these data. (9) Influence of Home and Street Environment. Throughout the above eye tables there is on the whole a larger percentage of normal eyes among the children of drinking parents than among the children of sober parents. The same thing was found by Barrington and Pearson when eyesight was correlated with overcrowding, bad economic condition of the home, and bad moral condition of the parents. Bad environmental conditions were found to be slightly associated with normal vision. "Can it be" they asked "Can it be" they asked "that these bad home conditions keep the children in the streets, and so relatively away from the bad environment and in relatively fresher air*?" This same question may be asked in the case of drinking parents. Miss Barrows has investigated this point. She found (1) the correlation between the drinking of the parents and how the child spends its spare time, and (2) the correlation between the child's vision and where it spends its spare time. In the first case "where the child spends its spare time" was divided into five groups for the boys and four for the girls; the groups for the boys were (1) "house," (2) partly house, (3) house and outdoor employment or occupation, (4) partly streets, (5) streets. "Partly house" includes children who spend most of their spare time in the house and "partly street" those who spend most of their time in the streets. For the girls there was no group (3) as practically none had an "outdoor" employment. The percentages are given below. The original tables are XLV to XLVIII inclusive in the Appendix. Father * "Inheritance of Vision and of the Relative Influence of Heredity and Environment on Sight." By A. Barrington and K. Pearson, p. 55. Son Mother Daughter FIG. 6. ACUITY OF VISION AND WHERE CHILD SPENDS ITS SPARE TIME (EDINBURGH). Normal 6/9 6/12 6/18 Rest Normal 6/9 6/12 6/18 Girl's Acuity of Vision FIG. 7. REFRACTION AND WHERE CHILD SPENDS ITS SPARE TIME (EDINBURGH). Rest Refraction Acuity of Vision From these percentages it is clear that there is a quite considerable connection between the drinking of the parents and the fact that the child spends its time in the streets. Alcoholic parents drive the child out of doors. The correlations show that the mother's drink is more likely to drive the child into the streets than the father's drink and that boys are more affected than girls. We must next examine the results which Miss Barrows found between the eyesight of the child and where it spent its time (Tables XLIX to LII in Appendix). Where Girl's spare time spent Where Boy's spare time spent An examination of the normals in these tables reveals a curious fact. In every case the largest percentage of normal eyes is found among children who are in the streets and the smallest percentage among children who are partly in the streets and partly in the house, while those children who are kept entirely in the house come half way between. This is not at all what we should expect; if being in the streets has a good influence on children's eyes, those children who are, at any rate, partly in the streets should have better eyes than those children who are kept entirely in the house, but we find nothing of the kind. The result of this curious fact is that if we divide our tables twice over and work out n we find that if we group "house" and " "part house and part streets" together we get a sensible correlation, but if we group streets and "part house and part streets" together we get practically half the correlation for the girls and boys in the acuity of vision tables and a very small one for the boys in the refraction table because we are combining the highest and lowest percentage in each case and this gives a value very close to the middle percentage which belongs to the "house only" group. When we look at "acuity of vision" measured by 6/9 and 6/12 we see for boys and girls the largest percentage with this type of vision in the "part streets" group, the smallest percentage in the streets, while the percentage in the house lies between the other two. We get the largest percentage of the worst type of vision in the streets and the smallest percentage in the house among the boys, and in the " part streets" group among the girls. Of hypermetropia and hypermetropic astigmatism we find the largest percentage in the "part streets" group and the smallest in the streets; while in the last two kinds of eyesight, mixed astigmatism and myopia, there seems to be a slight excess of myopia in the streets over children in the house and it is the other way round with mixed astigmatism. The curves for refraction and vision are interesting, showing a distinct difference of myopia between girls and boys. The boys with the worst vision are found indoors, the girls with the worst vision in the streets; the boys with the most myopia in the streets, and the girls with the most myopia indoors! Thus while the normal vision and normal refraction children are mostly in the streets, the worst vision girls and the myopic boys also frequent the streets. To test whether the "street" children were the older children, and therefore the more myopic, the average ages of the house and street boys and girls were calculated. The average age of the boys who spent their spare time in the streets was found to be 99 years, and in the house 9.2 years. The corresponding ages for the girls were 9.4 and 9.3 respectively. The six months difference in the case of the boys' ages may possibly account for some, but not for all the difference in myopia. Possibly also some of the boys prefer street to home for their spare time because they are myopic. It must at once be confessed that the relationships whatever they may be between street and home and eyesight are too slight and too entangled for any definite conclusions to be drawn from the present statistics. Drunkenness of parents does send the children into the streets; the children of the alcoholic parents have somewhat the best eyesight, and the children with the more normal vision and better refraction are most in the streets. But when we begin to think how we may explain the better sight of the children of parents who drink we are at once met, in this matter, by innumerable difficulties; the myopic boys are also more in the streets; the boys and girls who are partly in the streets have in all cases less normal sight than those wholly in the streets; they have also more myopia than those kept wholly in the house. Thus our correlations, which seemed to denote some significance of relationship between time in the streets and sight, are found to be the result of more than random variations, but variations of which we can give no obvious and unique explanation. Bad home environment sends the children into the streets, this is demonstrated; but greater time in the streets is not associated continuously and uniquely with better vision and refraction. (10) Parental Alcoholism and the Child Death Rate. In the C.O.S. Edinburgh Report the number of dead children is given for each family but the age at death is G. M. X. 4 |