246 



BIOLOGY OF DEATH 



The area covered is the United States birth registration 

 area. We see that with the very low death-birth ratio 

 of 56 in 1915, there was no si^uficant change till the 

 influenza year 1918, when the ratio rose to 73 per cent. 



eso 



I9IS 1919 I9» 1915 016 4917 ISia 



yCAR 

 ^'fi,o^;~S','J,'?°^,?!'^ change in percentage which deaths were of births in each of the 

 \a^}^}l^P^i ^T Vj«°°j^' , , ) : 1915 to 1919 for the United States (—--); and 

 1912 to 1920 for England and Wales( ). 



But in 1919, it promptly dropped back to the normal value 

 of 57.98, almost identical with the 1917 figure of 57.34. 



In England and Wales, the provisional figure indi- 

 cates that 1920 will show a lower value for the vital 

 index than that country has had for many years. 



So we see that neither a highly destructive war, nor 

 the most destructive epidemic since the Middle Ages, 

 serves more than to cause a momentary hesitation in the 

 steady onward march of population growth. 



