332 THE OLIVE LEAF. CHAP. 



Every room in every habitation is full of them ; and 

 could we magnify these germs so as to make them vis- 

 ible, we should see the atmosphere loaded with myriads 

 upon myriads of them, dancing up and down upon the 

 currents that pervade it. They are ever ready to alight 

 quick with life ; and they require the presence of only a 

 few simple conditions to start into full vigorous growth. 

 The great processes of fermentation and putrefaction are 

 caused by them ; and many diseases and epidemics 

 affecting both human beings and the animal and vege- 

 table world have been traced to their rapid increase and 

 luxuriant development, under certain favourable condi- 

 tions. They perform a most important function in the 

 economy of the world, taking to pieces effete substances 

 that had once formed part of living organized beings, 

 and so preparing the materials for entering into new 

 combinations. And while they thus attack the dead, 

 they also hasten the decay and dissolution of the weak 

 and dying. This action is undoubtedly most useful in 

 the lower world of plants and animals, leaving room for 

 the development of strong and useful organisms. But 

 in the higher world of man, where the same tendency of 

 nature operates equally, other considerations outweigh 

 the mere physical ones, and the medical man must step 

 in and do what he can to prevent this tendency, and so 

 save life. By the antiseptic mode of treatment that is, 

 by the careful exclusion of living germs from wounded 

 or exposed surfaces cures have been accomplished 

 which some years ago would have been considered 

 hopeless, and the most formidable operations may be 



