MIRACLES OF SCIENCE 



in the Canal Zone since 1905. It has not been pos- 

 sible to deal with malaria in quite so radical a fashion; 

 but this disease also has been held in check and in a 

 large measure rendered innocuous. 



As contrasted with the appalling mortality of the 

 workmen under the French regime, it is sufficient to 

 note that "in the year 1909 the annual death rate per 

 thousand of 11,662 white employes was 6.43 from dis- 

 ease, and 3.43 from violence; total' 9.86. Of Ameri- 

 cans, of the 8,386, including employes and their fami- 

 lies, the death rate per thousand was : From disease 

 4.05; from violence 2.27; total 6.32." So far as death 

 from disease is concerned, this showing can be dupli- 

 cated in very few communities of our most healthful 

 regions anywhere in the world. The average annual 

 death rate in the United States is about 17 per thou- 

 sand. 



THE CONQUEST OF TROPICAL FEVERS 



Interesting as these figures are in themselves, they 

 become doubly significant when we reflect that the 

 results which they herald have been achieved 

 through the rigid application of preventative meas- 

 ures based upon recently acquired knowledge as to 

 the causation of disease. It is true that Dr. A. F. A. 

 King, of Philadelphia, suggested as long ago as 1883 

 that malaria might be transmitted by the mosquito, 

 but no one paid any attention to his suggestion, and 

 it remained for Dr. Ronald Ross to show that the mos- 

 quito is the real offender so recently as 1898. 



Similarly the suggestion of Dr. Nott that yellow 

 fever might be transmitted by the mosquito, made in 



248 



