MICRO-ORGANISMS 



thing gives up its life, bacteria immediately 

 set to work upon its remains and forth- 

 with resolve them into their original chemi- 

 cal elements. We can prevent all this by 

 means which keep bacteria quiet, as when 

 we preserve meats and vegetables with 

 certain varieties of carbolic acid called 

 spices, for all spices can be made artifi- 

 cially out of coal tar. Or we may use na- 

 ture's efficient germicide, ice. Thus Nature 

 has a great cold-storage plant in the tun- 

 dras of Siberia, where the carcasses of big 

 mammoths have lain for unnumbered cen- 

 turies with their bodies so well preserved 

 that dogs at once help themselves to them 

 when they are dug out, and what the dogs 

 leave the bacteria at once dispose of. 



Geologists tell us that, as it is, entire 

 strata of rocks on the earth's surface are 

 largely made up of the skeletons of once 

 living forms. Hence if it were not for 

 bacteria, corpses would soon pile higher 

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