220 The Story of the Bacteria 



conditions which constantly threaten the 

 welfare of our physical machinery. So that 

 we are forced to pay attention to a host of 

 threatening agencies which in earlier and 

 simpler times could be safely ignored. This 

 is a part of the price which we must pay for 

 what we are pleased to call modern civilization. 

 It should not be forgotten that underlying 

 all the protective measures which have been 

 devised by science against infectious maladies 

 is the living body machine which each of us 

 controls for himself. If through the various 

 phases of unwholesome living so largely in 

 evidence to-day, the machine is lacking in 

 vigor, then by so much are the chances of 

 recovery lessened when the shadow of disease 

 falls across our path. 



Not too much work nor too much play; 

 not too much food and drink but enough; 

 good air and intelligent cleanliness in houses, 

 assembly places, and public conveyances 

 if these conditions be fulfilled in such way 

 and measure as the hygiene and sanitation of 

 the day demand, we shall go far to establish 

 our birthright to threescore years and ten. 



