Fig. 82.—The Right Axillary and Brachial Arteries, with Some of their Main Branches.
Note. “Destroy or paralyze the inhibitory nerve center, and instantly its controlling effect on the heart mechanism is lost, and the accelerating agent, being no longer under its normal restraint, runs riot. The heart’s action is increased, the pulse is quickened, an excess of blood is forced into the vessels, and from their becoming engorged and dilated the face gets flushed, all the usual concomitants of a general engorgement of the circulation being the result.”—Dr. George Harley, F.R.S., an eminent English medical author.
“The habitual use of alcohol produces a deleterious influence upon the whole economy. The digestive powers are weakened, the appetite is impaired, and the muscular system is enfeebled. The blood is impoverished, and nutrition is imperfect and disordered, as shown by the flabbiness of the skin and muscles, emaciation, or an abnormal accumulation of fat.”—Dr. Austin Flint, Senior, formerly Professor of the Practice of Medicine in Bellevue Medical College, and author of many standard medical works.
“The immoderate use of the strong kind of tobacco, which soldiers affect, is often very injurious to them, especially to very young soldiers. It renders them nervous and shaky, gives rise to palpitation, and is a factor in the production of the irritable or so-called “trotting-heart” and tends to impair the appetite and digestion.”—London Lancet.
“I never smoke because I have seen the most efficient proofs of the injurious effects of tobacco on the nervous system.”—Dr. Brown-Sequard, the eminent French physiologist.
“Tobacco, and especially cigarettes, being a depressant upon the heart, should be positively forbidden.”—Dr. J. M. Keating, on “Physical Development,” in Cyclopœdia of the Diseases of Children.
201. Effect of Tobacco upon the Heart. While tobacco poisons more or less almost every organ of the body, it is upon the heart that it works its most serious wrong. Upon this most important organ its destructive effect is to depress and paralyze. Especially does this apply to the young, whose bodies are not yet knit into the vigor that can brave invasion.
The nicotine of tobacco acts through the nerves that control the heart’s action. Under its baneful influence the motions of the heart are irregular, now feeble and fluttering, now thumping with apparently much force: but both these forms of disturbed action indicate an abnormal condition. Frequently there is severe pain in the heart, often dizziness with gasping breath, extreme pallor, and fainting.
The condition of the pulse is a guide to this state of the heart. In this the physician reads plainly the existence of the “tobacco heart,” an affection as clearly known among medical men as croup or measles. There are few conditions more distressing than the constant and impending suffering attending a tumultuous and fluttering heart. It is stated that one in every four of tobacco-users is subject, in some degree, to this disturbance. Test examinations of a large number of lads who had used cigarettes showed that only a very small percentage escaped cardiac trouble. Of older tobacco-users there are very few but have some warning of the hazard they invoke. Generally they suffer more or less from the tobacco heart, and if the nervous system or the heart be naturally feeble, they suffer all the more speedily and intensely.
Additional Experiments.
Experiment 93. Touch a few drops of blood fresh from the finger, with a strip of dry, smooth, neutral litmus paper, highly glazed to prevent the red corpuscles from penetrating into the test paper. Allow the blood to remain a short time; then wash it off with a stream of distilled water, when a blue spot upon a red or violet ground will be seen, indicating its alkaline reaction, due chiefly to the sodium phosphate and sodium carbonate.
Experiment 94. Place on a glass slide a thin layer of defibrinated blood; try to read printed matter through it. This cannot be done.
Experiment 95. To make blood transparent or laky. Place in each of three test tubes two or three teaspoonfuls of defibrinated blood, obtained from Experiment 89, labeled A, B, and C. A is for comparison. To B add five volumes of water, and warm slightly, noting the change of color by reflected and transmitted light. By reflected light it is much darker,—it looks almost black; but by transmitted light it is transparent. Test this by looking at printed matter as in Experiment 94.
Experiment 96. To fifteen or twenty drops of defibrinated blood in a test tube (labeled D) add five volumes of a 10-per-cent solution of common salt. It changes to a very bright, florid, brick-red color. Compare its color with A, B, and C. It is opaque.