Page:Popular Science Monthly Volume 25.djvu/283

Rh their slaughter encouraged in all legal ways. In this regard we can even look upon the rat-pit as serving a useful public purpose, and the rat-invasion theory, with reference to hogs, will receive a sooner final settlement." But Mr. Bergh will surely interfere here, and, when Greek meets Greek, will come the tug of war. The directions for the prevention of trichinæ in swine, p. 31, are excellent, although little is said about disinfection, above which cleanliness, inspection, branding diseased hogs, etc., are preferred.

"Hog-cholera" occupies pages 41 to 50. This chapter is short, but excellent. The cause of the disease, Bacillus suis, is well tracked down, the microscopical examinations well given, and the preventive measures thorough—down, in extreme cases, to slaughtering the infected animals in their own pens, and burning the latter, with all contaminated wooden utensils. Sheep and rabbits are subject to what is called "hog-cholera," and require attention in places where the disease prevails.

"Tape-worm" in hogs and cattle is treated of in a short but masterly way. The Tœnia medio-canellata comes from beef, which is especially dangerous when eaten raw or very rare. Tœnia solium comes from pork, and affects those who eat raw ham and underdone pork, and slightly smoked and cooked sausages. This chapter should have had a distinct heading, which is lacking, and may be overlooked by all who do not read the book regularly and carefully through. The same suggestion applies to the chapter on "Foot-and-Mouth Disease," or contagious eczema of cattle. This infection is also apt to implicate sheep, swine, goats, deer, occasionally horses, and sometimes dogs and turkeys. Cases in children in New York have occurred, apparently from the use of contaminated milk; and the disease is cropping up in various parts of the country, both far North and far West. It has possibly been imported by English cattle which have escaped quarantine inspection, although the spontaneous generation of a similar disease, where cattle live in marshes and filth, can not well be denied. Eczema, or salt-rheum, is the most common skin affection in human beings, and how much of it comes from cattle is not yet determined. Bollinger says: "Notwithstanding the ruling opinion to the contrary, the disease is much more common among human beings than is suspected." The suggestion of Dr. Billings, that milk should be examined for much more than mere dilution with more or less pure water, is worthy of all consideration. This suggestion receives still greater emphasis in the chapter on "Tuberculosis in Cattle," pages 52 to 74, which is all too short, although pregnant with information. The credit of first calling attention to this dire disease is given to Gerlach, to whom Dr. Billings has dedicated his book. The notion that pulmonary consumption may be conveyed by the milk of tuberculosis in cows is not a pleasant one. In the opinion of the reviewer, consumption is often a foul-air disease, caused quite as much, and even oftener, by inhaling foul air. as from mere exposure to cold and wet. Dr. Billings says, "In Germany, where the majority of the milch-cows are stall-fed, and that, too, in poorly-ventilated, ill-arranged, and filthy stables, this disease has acquired an extension of which we can at present make no appreciation in this country," although we have an inkling of it among swill-fed cows. Bollinger reproduced the disease in pigs, calves, lambs, and rabbits, fed on milk from tuberculous cows. Billings is undoubtedly right when he says, page 78, that "such milk does contain elements of a specifically infectious character, and there is no question that laws should be made, and executed also, to prevent the sale of such milk for human consumption, either by itself, or mixed with other milk, in no matter how small quantities. No such milk should be sold. The specific infection of milk from tuberculous cows is no trifling matter; it is one of life and death." Consumption, scrofula, and marasmus are only too common among the hundreds of thousands of babies that are yearly brought up on poor cow's milk. However important trichiniasis may be, this far exceeds it.

Every consumptive cow should be branded by expert men. Its milk can only be given with safety to swine, after being boiled; and, although the notion is not a nice one, the doctor thinks they should be fattened and killed, as the meat is not injurious when well cooked. It is to be presumed that even "the eaters of lights" will not consume the lungs of such animals, and the liver and kidneys also must be viewed with much suspicion.

metaphysician Sir William Hamilton, Professor of Logic in the University of Edinburgh, got embroiled in controversy with the phrenologists, and paused in his career of abstract speculation to make investigations into brain-structure, skull-measurement, and alleged "bumps" of faculty, and all for the confutation of phrenological doctrine. Another metaphysician of Edinburgh seems to have encountered a similar difficulty in his prosecution of the subject of mind. His main studies had been in the region of mental philosophy, as pursued by the old school, without especial reference to its corporeal foundations in the nervous structures of organized beings. But the modern scientific movement set so strongly in the direction of physiological inquiries, or the extension of cerebral psychology, that Dr. Calderwood found it necessary to pause, as his great predecessor had done before, and give attention to the new questions that have arisen from the study of the organic side of the subject.

Dr. Calderwood is unquestionably well imbued with the spirit of the scientific method, as is shown both by his recognition of the necessity for the systematic study of bodily conditions to any one who would