THE CONQUEST OF DISEASE 



cats annually. It is necessary that such meas- 

 ures be adopted or the cities would become 

 overrun with ownerless dogs. Out of 7000 

 stray dogs captured by the Board of Health 

 in New York in one month, only 2 per cent, 

 were claimed or wanted by any one. The rest 

 were left in the hands of the authorities to be 

 disposed of. It is just such stray animals as 

 these that are used to increase biological know- 

 ledge and help humanity. Which is the better 

 way for them to die, in contributing to man's 

 relief from the scourge of disease or in having 

 their lives ignominiously ended by being suf- 

 focated in closed chambers filled with carbonic 

 acid gas ? 



