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[27] "If the amount of alcohol be increased, or the repet.i.tion become frequent, some part of it undergoes acid fermentation in the stomach, and acid eructations or vomitings occur. With these phenomena are a.s.sociated catarrh of the stomach and liver with its characteristic symptoms,--loss of appet.i.te, feeble digestion, sallowness, mental depression, and headache."--James C. Wilson, Professor in the Jefferson Medical College, Philadelphia.
"Man has recourse to alcohol, not for the minute quant.i.ty of energy which may be supplied by itself, but for its powerful influence on the distribution of the energy furnished by other things. That influence is a very complex one."--Professor Michael Foster.
[28] "When constantly irritated by the direct action of alcoholic drinks, the stomach gradually undergoes lasting structural changes. Its vessels remain dilated and congested, its connective tissue becomes excessive, its power of secreting gastric juice diminishes, and its mucous secretions abnormally abundant."--H. Newell Martin, late Professor of Physiology in Johns Hopkins University.
"Chemical experiments have demonstrated that the action of alcohol on the digestive fluids is to destroy its active principle, the pepsin, thus confirming the observations of physiologists that its use gives ride to the most serious disorders of the stomach and the most malignant aberrations of the entire economy."--Professor E. C. Youmans, author of standard scientific works.
"The structural changes induced by habitual use of alcohol and the action of this agent on the pepsin, seriously impair the digestive power. Hence it is, that those who are habitual consumers of alcoholic fluids suffer from disorders o digestion."--Robert Bartholow, recently Professor of Materia Medica in the University of Pennsylvania.
"Alcohol in any appreciable quant.i.ty diminishes the solvent power of the gastric fluid so as to interfere with the process of digestion instead of aiding it."--Professor W. B. Carpenter, the eminent English physiologist.
[29] "Cirrhosis of the liver is notoriously frequent among drunkards, and is in fact almost, though not absolutely, confined to them."--Robert T.
Edes, formerly Professor of Materia Medica in Harvard Medical College.
"Alcohol acts on the liver by producing enlargement of that organ, and a fat deposit, or 'hob-nailed' liver mentioned by the English writers."--Professor W. B. Carpenter.
[30] Preparation of Artificial Gastric Juice. _(a)_ Take part of the cardiac end of the pig's stomach, which has been previously opened and washed rapidly in cold water, and spread it, mucous surface upwards, on the convex surface of an inverted capsule. Sc.r.a.pe the mucous surface firmly with the back of a knife blade, and rub up the sc.r.a.pings in a mortar with fine sand. Add water, and rub up the whole vigorously for some time, and filter. The filtrate is an artificial gastric juice.
_(b)_ From the cardiac end of a pig's stomach detach the mucous membrane in shreds, dry them between folds of blotting-paper, place them in a bottle, and cover them with strong glycerine for several days. The glycerine dissolves the pepsin, and on filtering, a glycerine extract with high digestive properties is obtained.
These artificial juices, when added to hydrochloric acid of the proper strength, have high digestive powers.
Instead of _(a)_ or _(b)_ use the artificial pepsin prepared for the market by the wholesale manufacturers of such goods.
[31] The cause of the clotting of blood is not yet fully understood.
Although the process has been thoroughly investigated we have not yet a satisfactory explanation why the circulating blood does not clot in healthy blood-vessels. The ablest physiologists of our day do not, as formerly, regard the process as a so-called vital, but a purely chemical one.
[32] Serous Membranes.--The serous membranes form shut sacs, of which one portion is applied to the walls of the cavity which it lines; the other is reflected over the surface of the organ or organs contained in the cavity. The sac is completely closed, so that no communication exists between the serous cavity and the parts in its neighborhood. The various serous membranes are the _pleura_ which envelops the lungs; the _pericardium_ which surrounds the heart; the _peritoneum_ which invests the viscera of the abdomen, and the _arachnoid_ in the spinal ca.n.a.l and cranial cavity. In health the serous membranes secrete only sufficient fluid to lubricate and keep soft and smooth the opposing surfaces.
[33] A correct idea may be formed of the arrangement of the pericardium around the heart by recalling how a boy puts on and wears his toboggan cap. The pericardium encloses the heart exactly as this cap covers the boy's head.
[34] "Alcohol taken in small and single doses, acts almost exclusively on the brain and the blood-vessels of the brain, whereas taken in large and repeated doses its chief effects are always nervous effects. The first effects of alcohol on the function of inhibition are to paralyze the controlling nerves, so that the blood-centers are dilated, and more blood is let into the brain. In consequence of this flushing of the brain, its nerve centers are asked to do more work."--Dr. T. S. Clouston, Medical Superintendent of the Royal Asylum, Edinburgh.
"Alcoholic drinks prevent the natural changes going on in the blood, and obstruct the nutritive and reparative functions."--Professor E. L.
Youmans, well-known scientist and author of _Cla.s.s Book of Chemistry_.
[35] The word "cell" is not used in this connection in its technical signification of a histological unit of the body (sec. 12), but merely in its primary sense of a small cavity
[36] "The student must guard himself against the idea that arterial blood contains no carbonic acid, and venous blood no oxygen. In pa.s.sing through the lungs venous blood loses only a part of its carbonic acid; and arterial blood, in pa.s.sing through the tissues, loses only a part of its oxygen. In blood, however venous, there is in health always some oxygen; and in even the brightest arterial blood there is actually more carbonic acid than oxygen."--T. H. Huxley.
[37] "Consumption is a disease which can be taken from others, and is not simply caused by colds. A cold may make it easier to take the disease. It is usually caused by germs which enter the body with the air breathed. The matter which consumptives cough or spit up contains these germs in great numbers--frequently millions are discharged in a single day. This matter spit upon the floor, wall, or elsewhere is apt to dry, become pulverized, and float in the air as dust. The dust contains the germs, and thus they enter the body with the air breathed. The breath of a consumptive does not contain the germs and will not produce the disease. A well person catches the disease from a consumptive only by in some way taking in the matter coughed up by the consumptive."--Extract from a circular issued by the Board of Health of New York City.
[38] "The lungs from the congested state of their vessels produced by alcohol are more subject to the influence of cold, the result being frequent attacks of bronchitis. It has been recognized of late years that there is a peculiar form of consumption of the lungs which is very rapidly fatal and found only in alcohol drinkers."--Professor H. Newell Martin.
[39] "The relation to Bright's Disease is not so clearly made out as is a.s.sumed by some writers, though I must confess to myself sharing the popular belief that alcohol is one among its most important factors."--Robert T. Edes, M.D.
[40] Thus the fibers which pa.s.s 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 ill.u.s.trate 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 eyeb.a.l.l.s 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 inst.i.tuted 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 princ.i.p.al 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 a.s.surance, 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.
[52] The teacher or student who is disposed to study the subject more thoroughly and in more detail than is possible in a cla.s.s text-book, will find all that is needed in the following excellent books, which are readily obtained by purchase, or may be found in the public libraries of larger towns: Dulles' _Accidents and Emergencies;_ Pilcher's _First Aid in Illness and Injury_; Doty's _Prompt Aid to the Injured;_ and Johnston's "Surgical Injuries and Surgical Diseases," a special article in Roosevelt's _In Sickness and in Health_.
[53] "A tourniquet is a bandage, handkerchief, or strap of webbing, into the middle of which a stone, a potato, a small block of wood, or any hard, smooth body is tied. The band is tied loosely about the limb, the hard body is held over the artery to be constricted, and a stick is inserted beneath the band on the opposite side of the limb and used to twist the band in such a way that the limb is tightly constricted thereby, and the hard body thus made to compress the artery (Fig. 160).
"The entire circ.u.mference of the limb may be constricted by any sort of elastic band or rubber tube, or any other strong elastic material pa.s.sed around the limb several times on a stretch, drawn tight and tied in a knot. In this way, bleeding may be stopped at once from the largest arteries. The longer and softer the tube the better. It requires no skill and but little knowledge of anatomy to apply it efficiently." Alexander B.
Johnson, Surgeon to Roosevelt Hospital, New York City.
[54] Corrosive sublimate is probably the most powerful disinfectant known.
A solution of one part in 2000 will destroy microscopic organisms. Two teaspoonfuls of this substance will make a solution strong enough to kill all disease germs.
[55] The burning of sulphur produces sulphurous acid, which is an irrespirable gas. The person who lights the sulphur must, therefore, immediately leave the room, and after the lapse of the proper time, must hold his breath as he enters the room to open the windows and let out the gas. After fumigation, plastered walls should be white-washed, the woodwork well scrubbed with carbolic soap, and painted portions repainted.
[56] Put copperas in a pail of water, in such quant.i.ty that some may constantly remain undissolved at the bottom. This makes a saturated solution. To every privy or water-closet, allow one pint of the solution for every four persons when cholera is about. To keep privies from being offensive, pour one pint into each seat, night and morning.
[57] "While physiology is one of the biological sciences, it should be clearly recognized that it is not, like botany or zoology, a science of observation and description; but rather, like physics or chemistry, a science of experiment. While the amount of experimental instruction (not involving vivisection or experiment otherwise unsuitable) that may with propriety be given in the high school is neither small nor unimportant, the limitations to such experimental teaching, both as to kind and as to amount, are plainly indicated.
"The obvious limitations to experimental work in physiology in the high school, already referred to, make it necessary for the student to acquire much of the desired knowledge from the text-book only. Nevertheless, much may be done by a thoughtful and ingenious teacher to make such knowledge real, by the aid of suitable practical exercises and demonstrations."--_Report of the Committee of Ten on Secondary School Studies_.