Biology and Medicine 417 



factory or stnro costs the employer from $35 to $70, we 

 api)reciate the iinportauce of tlie worker's health from the 

 standpoint of dollars and cents alone. Add to this the dan- 

 ger of the crowded factory as a center of contagion and con- 

 ^ ecpient menace to an entire community, and we can realize 

 tile necessity of industrial hygiene as a public measure. 

 During tlie recent war this work became even more than 

 usually imperative, for the city of ordinarily 20,000 or 

 30,000 was suddenly swelled to one of 100,000 or more. The 

 housing problem became acute and with it arose the even 

 more serious ones of water supply, sewage disposal and of 

 all the factors which make for health or disease in any 

 connnunity. Then too the great munition factories, ship- 

 building plants, and all the other war activities sprang up 

 like mushrooms over night, bringing with them teeming life 

 in new locations and consequent menace to the public health, 

 and increasing the opportunities as well as the responsibilities 

 of the men of the service. 



If we drink water, and most of us do nowadays by virtue 

 cither of choice or necessity, we will be interested to know 

 that when we travel on a train from one state to another 

 our drinking supply is safeguarded by the watchful care of 

 the U. S. Public Health Service. These supplies are under 

 constant supervision by agents of the Service, and if they 

 do not meet the standard set they are condemned and the 

 carriers obliged to improve them or obtain new supplies 

 elsewhere. 



In addition to a station in Hawaii for the study and treat- 

 ment of lepers, whose investigations in the treatment with 

 derivatives of chaulmoogra oil, are meeting with a consider- 

 able degree of success, the Service has established a national 

 home for lepers in the United States, a number of which un- 

 fortunate people live among us. 



The Service also maintains a tuberculosis sanitarium at 

 Fort Stanton, N. M., and numerous hospitals for the care of 

 sick or disabled soldiers, sailors and other government 

 employees. 



One might continue indefinitely to rehearse the activities 

 of the U. S. Public Health Service, not to mention those of 

 the many other agencies for protecting public health, but the 

 foregoing must suffice as a bird 's eye view of this great and 

 ever-growing field. 



In all the great work which biology has done for man 

 there is none more splendid than its service in the field of 

 preventive medicine. 



