[42] According to the Annual Report of New York State Reformatory, for 1896, drunkenness among the inmates can be clearly traced to no less than 38 per cent of the fathers and mothers only.
Drunkenness among the parents of 38 per cent of the prisoners in a reformatory of this kind is a high and a serious percentage. It shows that the demoralizing influence of drink is apt to destroy the future of the child as well as the character of the parent.
“There is a marked tendency in nature to transmit all diseased conditions. Thus the children of consumptive parents are apt to be consumptive. But, of all agents, alcohol is the most potent in establishing a heredity that exhibits itself in the destruction of mind and body. There is not only a propensity transmitted, but an actual disease of the nervous system.”—Dr. Willard Parker.
[43] “It is very certain that many infants annually perish from this single cause.”—Reese’s Manual of Toxicology.
[44] If an eye removed from its socket be stripped posteriorly of the sclerotic coat, an inverted image or the field of view will be seen on the retina; but if the lens or other part of the refractive media be removed, the image will become blurred or disappear altogether.
[45] This change in the convexity of the lens is only a slight one, as the difference in the focal point between rays from an object twenty feet distant and one four inches distant is only one-tenth of an inch. While this muscular action is taking place, the pupil contracts and the eyeballs converge by the action of the internal rectus muscles. These three acts are due to the third nerve (the motor oculi). This is necessary in order that each part should he imprinted on the same portion of the retina, otherwise there would be double vision.
[46] The Germans have a quaint proverb that one should never rub his eyes, except with his elbows!
[47] “The deleterious effect of tobacco upon eyesight is an acknowledged fact. The Belgian government instituted an investigation into the cause of the prevalence of color-blindness. The unanimous verdict of the experts making the examination was that the use of tobacco was one of the principal causes of this defect of vision.
“The dimness of sight caused by alcohol or tobacco has long been clinically recognized, although not until recently accurately understood. The main facts can now be stated with much assurance, since the publication of an article by Uhthoff which leaves little more to be said. He examined one thousand patients who were detained in hospital because of alcoholic excess, and out of these found a total of eye diseases of about thirty per cent.
“Commonly both eyes are affected, and the progress of the disease is slow, both in culmination and in recovery.... Treatment demands entire abstinence.”—Henry D. Noyes, Professor of Otology in the Bellevue Hospital Medical College, New York.
[48] “The student who will take a little trouble in noticing the ears of the persons whom he meets from day to day will be greatly interested and surprised to see how much the auricle varies. It may be a thick and clumsy ear or a beautifully delicate one; long and narrow or short and broad, may have a neatly formed and distinct lobule, or one that is heavy, ungainly, and united to the cheek so as hardly to form a separate part of the auricle, may hug the head closely or flare outward so as to form almost two wings to the head. In art, and especially in medallion portraits, in which the ear is a marked (because central) feature, the auricle is of great importance”—William W. Keen, M.D., editor of Gray’s Anatomy.
[49] The organ of Corti is a very complicated structure which it is needless to describe in this connection. It consists essentially of modified ephithelial cells floated upon the auditory epithelium, or basilar membrane, of the cochlea. There is a series of fibers, each made of two parts sloped against each other like the rafters of a roof. It is estimated that there are no less than 3000 of these arches in the human ear, placed side by side in a continuous series along the whole length of the basilar membrane. Resting on these arches are numbers of conical epithelial cells, from the free surface of which bundles of stiff hairs (cilia) project. The fact that these hair-cells are connected with the fibers of the cochlear division of the auditory nerve suggests that they must play an important part in auditory sensation.
[50] The voices of boys “break,” or “change,” because of the sudden growth or enlargement of the larynx, and consequent increase in length of the vocal cords, at from fourteen to sixteen years of age. No such enlargement takes place in the larynxes of girls: therefore their voices undergo no such sudden change.
[51] This experiment and several others in this book, are taken from Professor Bowditch’s little book called Hints for Teachers of Physiology, a work which should be mastered by every teacher of physiology in higher schools.