xix BACTERIA AND DISEASES 287 



6. Convalescence, or the time it takes to grow strong 

 and well. 



We shall now consider more in detail a few of the 

 common communicable diseases. 



195. Consumption. We have already learned that 

 consumption destroys more lives in this country than any 

 other disease. We are now beginning to understand the 

 cause, nature, means of prevention, 

 and treatment of this dreaded dis- 

 ease, and we may hope that as the 

 general public becomes more intelli- 

 gent on this subject fewer deaths 

 will be caused by it. Consumption 

 can be taken only from a person 



rr ,, ,. Tr ., FlG. 155. Bacteria of 



suffering from the disease. If the consumption, 



sputum is allowed to dry on the 

 ground, the germs get into the air and must be inhaled 

 with the air we breathe. We know that the germs of 

 consumption occur in meats and milk from diseased 

 cattle and unless destroyed by thorough cooking may 

 get into the body, but we cannot say positively that 

 they can cause consumption in man ; most scientists 

 think they can. There are, of course, many other ways 

 in which persons can take the germs. 



When healthy persons live with consumptives great 

 care must be exercised, for it is easy to take the germs 

 by sleeping in the same bed, using the same eating and 

 drinking utensils, wiping on the same towel, kissing and 

 caressing, and especially by carelessness in disposing of 

 the sputum and excretions. 



