308 AGRICULTURAL BACTERIOLOGY. 



CHAPTER XIII. 



PRESERVATION OF FOOD PRODUCTS FROM 

 BACTERIA. 



IT is not only the fallen monarch of the forest which, aftcr 

 se'rving its usefulness, is attacked by molds and bacteria and 

 slowly decomposed. It is as truly every bit of wood which 

 the farmer may have built into his dwelling, unless he carefully 

 protects it. His fence posts, the sills of his houses and barns, 

 in short every bit of timber which he has laboriously fashioned, 

 is sure to undergo decay if it is exposed to sufficient moisture. 

 This slow decay causes his barn and every wooden structure 

 to settle, and the roof to cave in unless he gives it proper 

 attention ; even with the best of care his wooden structures 

 eventually yield to the attack of microorganisms. Moreover, 

 his living trees are not exempt from a similar process of decay 

 due to molds and bacteria. The fungi make their way into 

 the living tree and cause the decay of its interior just as they 

 do that of a fallen trunk. They may even attack the living 

 parts of a tree, slowly sapping its strength and eventually kill- 

 ing it. Many a valuable tree is thus destroyed. All around 

 his farm the farmer finds a general decay of organic matter, and 

 it is one of his tasks to prevent it or make it as slow as possible. 

 He tries to guard his wooden structures from moisture ; he 

 covers them with a protecting paint, and in every possible way 

 endeavors to check the action of the decomposing organisms. 



But in the preservation of food products is found the 

 greatest difficulty, since these are so readily attacked by bac- 

 teria. Bacteria will cause the rotting of the farmer's crops 



