[40] Thus the fibers which pass out from the sacral plexus in the loins, and extend by means of the great sciatic nerve and its branches to the ends of the toes, may be more than a yard long.

[41] Remarkable instances are cited to illustrate the imperative demand for sleep.  Gunner boys have been known to fall asleep during the height of a naval battle, owing to the fatigue occasioned by the arduous labor in carrying ammunition for the gunner.  A case is reported of a captain of a British frigate who fell asleep and remained so for two hours beside one of the largest guns of his vessel, the gun being served vigorously all the time.  Whole companies of men have been known to sleep while on the march during an arduous campaign.  Cavalrymen and frontiersmen have slept soundly in the saddle during the exhausting campaigns against the Indians.

[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.