BIOLOGY AND PROGRESS 217 



known and means of prevention have been worked 

 out for most of them. These preventive measures 

 are of such a character, however, that one family 

 cannot alone successfully observe them. This is 

 due to the simple fact that so many of the germs 

 are carried from person to person by wind, water, 

 or milk, environmental facts with which man is 

 constantly in contact. A community of effort is 

 necessary to prevent the great scourges of civiliza- 

 tion. Much progress has been made in the more 

 enlightened communities in reducing the death rate 

 from diphtheria, typhoid, smallpox and tubercu- 

 losis but the devastations of the great war to- 

 gether with lack of care and adequate food bid 

 fair to give some of these terrible diseases a new 

 start and thus multiply the possibilities of com- 

 munication. 



In America much effort has been given to 

 saving the babies and this intelligent work has 

 yielded important results as the decline in death 

 rate clearly indicates. In addition to this most 

 worth-while application of biological science, at- 

 tention should be directed to the important fact 

 that there is a sharp increase in the death rate of 

 adults between the 45th and 50th years, just at 

 the time when man is at his maximum efficiency. 

 Here is a field in which critical studies should 

 enable us to make marked progress. 



What does biology contribute to that aspect of 



