1865,] The Laws of Health. 151 



author has been compelled to press his large knowledge of sanitary 

 science into the service of the army, and that he was not induced to call 

 it a book on general public health, as, after all, the necessities of sani- 

 tary rules for the soldier, independent of the civilian, are of very small 

 account, and might have been comprehended in a very few pages. In 

 fact, nearly 500 out of the 600 pages, of which the book consists, is 

 occupied with the discussion of first principles, which apply to sailors 

 and artisans, to merchants and beggars, as well as to soldiers. The 

 general subject of the work is treated under the heads, Water, Air, 

 Food, Soil, Habitation, Clothes, Climate, and Disease. 



The first subject treated is water, a point of first-rate importance, 

 no doubt, both in relation to the health of soldiers and the community 

 at large. Yet it is a strange fact that scarcely anything has been so 

 much neglected by the armies and cities of Europe. On this point our 

 civilization lags immensely behind that of the ancient Eomans, and 

 their ruined aqueducts are a silent reproach to modern civilization. 

 Much of the disease of our army in India, more especially cholera, 

 can be traced to the utter disregard of water supply, and the same may 

 be said with regard to the visitation of cholera in the towns and villages 

 of Great Britain. So palpably was this the case, that London, Man- 

 chester, Liverpool, Glasgow, and other great cities, have gone to an 

 enormous expense to obtain pure water for their inhabitants. At the 

 same time there is great popular ignorance on this subject. Although 

 it has been shown over and over again that the surface wells in large 

 towns are almost always contaminated with impurities, yet these wells 

 are had recourse to, and exist in, almost every town in the kingdom. 

 Strange to say, these wells and pumps when attacked are almost always 

 sure to have their medical apologists, and the knowledge of one set of 

 medical men is made to oppose the other. At the present moment it 

 is a great defect in om medical education, that there is no teaching on 

 the subject of preventive medicine, and young men are turned out of 

 our medical schools as ignorant of sanitary science, as their less in- 

 structed neighbours. 



Dr. Parkes examines the whole question of water supply with 

 great ability. He first considers the quantity necessary for men to 

 drink in health, and gives us an approximation to the average quantity 

 required in twenty -four hours, as halt' an ounce to every pound which the 

 body weighs. Thus a man weighing 1501bs. would require 75 ounces 

 of water in the day. This, we believe, is a good approximation. Of 

 course the quantity will vary according to the activity of the skin in 

 getting rid of water, which again depends on occupation, climate, 

 and the temperature of the external air. The quantity required for all 

 the washing and other purposes of a residence depends very much on 

 the habits of a people. In 14 English towns of second-rate magni- 

 tude, 24 gallons a day are supplied to each inhabitant. In Manchester, 

 20 gallons ; in Liverpool, 30 gallons ; in London, 50 gallons ; in 

 New York, 300 gallons. Ancient Imperial Eome received from 300 

 to 340 gallons per head daily. 



Dr Parkes has a capital chapter on the examination of water, so 

 that any person with a knowledge of how to use a microscope, and the 



