MICROBES, MOULDS, AND YEAST. 20g 



the importance of bacteria to mankind is very great. 

 Grass and Clover pastures would be impossible without the 

 bacteria of clover, those of farmyard manure, and those 

 of putrefaction. The cow, feeding on these pastures, is 

 probably assisted by bacteria to digest its food. The 

 change of the cow's milk to butter and cheese depends 

 upon the action of bacteria. It would be impossible to 

 turn hides into leather without the aid of bacteria. 

 The preservation of meat involves a complete study of 

 them. Most of the diseases which attack cattle are also 

 due to them. If the cow should be cut, or bruised, it is 

 advisable to tar the wound, or treat it antiseptically. 

 Most of these antiseptics, such as tar, pitch, resin, have 

 probably been called into existence chiefly, because plants 

 had to protect themselves against the spores of fungi 

 and bacteria. 



A very simple case will show how remarkably 

 deficient even careful and well-educated people may be 

 in scientific imagination, and what serious evils may 

 arise from the want of that faculty. A doctor ordered 

 the destruction of the bedding of a patient who had 

 been suffering from an infectious disease. The sick- 

 room happened to be on the top flat of a tenement. 

 The bedding was pulled down the common stair, 

 touching every step on the way, then carted out 

 through the street, and burned in a waste place. Thus 

 the air of the staircase and of the street, not to speak 

 of the people passing, were abundantly supplied with 

 active and vigorous germs of disease. Far more, in 

 fact, were distributed by treating the bedding in this 

 way than if it had been left in its place. 



Bacteriology is a study in itself, and the methods of 

 sterilisation, etc., can only be learned in a laboratory. 

 It is, however, not difficult to obtain bacteria for 



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