No. 4.] AGRICULTURE AND HEALTH. 277 



cide to bis potato vines during the growing season will 

 insure the best crop. So, also, with his fruit trees ; a care- 

 ful application of spraying liquid of such strength as not to 

 injure the trees, but strong enough to destroy the insect 

 pests, will insure the best crop of fair and handsome fruit. 



So the health officer, who applies disinfectants judiciously 

 and intelligently, will be rewarded in finding that scarlet 

 fever, diphtheria and other pests of mankind will not recur 

 in the same household unless introduced from outside 

 sources. 



I cannot close this comparison without reference to the 

 labors of one man who has lately passed away from earth to 

 his great reward, and who was a common benefactor both 

 of the medical profession and of those wdio till the soil. He 

 was much more, — he was a benefactor to the whole human 

 race. I mean Louis Pasteur. Born in the little town of 

 Dole, in France, of humble parentage, his father was a 

 veteran French soldier, afterward a tanner. The son Louis 

 early in life became an enthusiastic student of nature and 

 of natural laws. More than a half-centurv ago he had besfun 

 the course of experimental research which destined him to 

 become one of the greatest allies of the medical profession 

 and of agriculture that the world has ever known. 



One of his first triumphs was the discovery of the cause 

 of the silkworm disease. In 1849 and 1850 the silkworms 

 were attacked with a parasitic disease which caused the loss 

 to France, in the silkworm industry alone, of $20,000,000 

 in a single year. The plague spread to vSpain and Italy, and 

 finally no eastern country was exempt from its ravages 

 except Japan. Pasteur was urged to study the sul)ject, with 

 the view of finding the cause of the disease and its preven- 

 tion. He gave his whole attention to this question for 

 nearly three years, and so zealously did he pursue his ex- 

 periments that his health broke down, he became enfeebled, 

 and was stricken with partial paralysis in 18(58, while he 

 was in the midst of this important w^ork. He had, how- 

 ever, already found the cause and the mode of prevention, 

 which consisted in separating the healthy moths from those 

 which were sick, carrying out the true principle of isolation 

 in infectious diseases, and thus he restored the silk industry 



