CHAPTER XIV 



BACTERIA; DISEASES THAT SPREAD AND DISINFECT- 

 ANTS; CARE OF THE SICK ROOM 



419. The Work done by Bacteria. We all know that in 

 hot weather milk, meat, and every kind of moist food quickly 

 becomes bad. In a previous chapter we learned that a 

 glass of sweetened water or sweet cider, if left in a warm 

 place, soon begins to ferment or "work" (Chapter V). 

 Everybody knows that if the dead body of some animal is 

 buried in the ground, it soon begins to putrefy and after 

 a time almost entirely disappears. 



All these and countless other wonderful changes in dead 

 organic matter, known as putrefaction or fermentation, are due 

 to the work done by myriads of living organisms called 

 bacteria. The terms germs, microorganisms, and microbes are 

 commonly applied to certain low forms of plant and animal 

 life of microscopic size. Probably there are microorganisms 

 that cannot be seen even with the help of the highest 

 power of the microscope. 



420. Nature and Propagation of Bacteria. Bacteria are 

 low forms of plant life which appear as the tiniest bright rods 

 or dots when examined with a microscope of great power. 



When bacteria gain an entrance into fluid suitable for 

 their growth they multiply by division with incredible 

 rapidity. Thus, in a cupful of milk in the course of one 

 hot night millions upon millions of bacteria may develop. 



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