906 



SCIENCE. 



[X. S. Vol. XXI. No. 546. 



•'another existed, but these were largely em- 

 pirical and quite as often directed to the 

 convenience of mankind as to their sani- 

 tary safety. In this class belong the 

 Llosaic code; the water supply introduced 

 into Jerusalem by Hezekiah; the sanitary 

 engineering of Empedocles; the Cloaca 

 maxima; the water supplies of ancient 

 lilycenas and of Rome"; and all the earlier, 

 and too often futile, forms of quarantine. 

 Even the art of inoculation for smallpox 

 was only an ingenious knack introduced 

 from the east, where it had been long used 

 empirically, and although it was a public 

 health measure now of the utmost interest 

 and capable at the time of great practical 

 service, it had until recently no scientific 

 basis, but belonged in nearly the same 

 class as the amulets and charms, the pray- 

 ers and incantations, of the superstitious. 



It was not until the middle of the eight- 

 eenth century, namely, in 1767, that Sir 

 George Baker, by the use of the methods of 

 pure inductive reasoning, made the first 

 scientific discovery in public health science 

 in the subdivision of epidemiology, namely, 

 that the epidemic colic of Devonshire, Eng- 

 land, was due to an obscure poisoning by 

 lead conveyed through the common cider 

 used for drinking in that district. In 

 1774 the foundations of state hygiene and 

 sanitation were laid in consequence of the 

 patient investigations and startling revela- 

 tions of John Howard, by an act of Parlia- 

 ment providing for the sanitation of jails 

 and prisons. The beginnings of marine 

 hygiene and sanitation appear in 1776, 

 ■when Captain Cook, the navigator, was 

 awarded the Copley medal of the Royal 

 Society for his remarkable success in pro- 

 tecting the lives of his sailors on his sec- 

 ond voyage. In 1796 Edward Jenner, 

 working also in a strictly scientific man- 

 ner, and employing the methods of rigid 

 inductive research, laid securely for all 



time the foundations of personal hygiene 

 and immunization, by showing how we can 

 produce at will such modifications of the 

 physiological resistance or susceptibility of 

 the human body as to make it immune to 

 smallpox. 



The importance of these fundamental 

 and splendid discoveries, not only to the 

 public health of the time, but far more to 

 the development of public health science 

 in all the centuries to come, is incalcu- 

 lable. Reduced to their lowest terms, we 

 have in these eighteenth century discoveries 

 the germs of some of the most important 

 divisions of public health science as it is 

 to-day, namely, (1) epidemiology, (2) 

 sanitation of the environment, and (3) im- 

 munization of the human mechanism, this 

 last the most marvelous phenomenon hith- 

 erto discovered in personal hygiene. 



Time fails me to do more than name 

 some of the principal steps in the advance- 

 ment of public health science in the nine- 

 teenth century. We have, for example, 

 in 1802, the beginnings of factory hygiene 

 and sanitation ; in 1829, the first municipal 

 water filter, one acre in area, constructed 

 for the Chelsea Company of London; in 

 1834, recognition of the important relation 

 of poverty to public health, in the famous 

 report of the Poor Law Commissioners of 

 that year; in 1839, the beginnings of reg- 

 istration and accurate vital statistics; in 

 1842, an important report on the sanitary 

 condition of the laboring population of 

 England ; and in 1843, a similar report on 

 the health of towns; in 1854, for the first 

 time clearly taught, the lesson, even yet 

 not properly taken to heart, that drinking 

 water may be the ready vehicle of a ter- 

 rible epidemic of cholera. About 1860, 

 striking epidemics of trichinosis first came 

 into public notice, and here, also, belongs 

 the magnificent work of Pasteur, while in 

 1868, Lister, following in the footsteps of 



