SCIENCE OF AGRICULTURE. 129' 



The first escape and are lost ; the second poisons 

 animals, and affords no nourishment to plants, and a 

 small part of the yeast only remains to form geine. 

 Sugar and gum exposed to air, moisture, and a tem- 

 perature of from 65*^ to 70° F., are susceptible of 

 acid fermentation. The products are vinegar, car- 

 bonic acid gas, and some other acids. Plere also is 

 almost a total loss of portions of the plant, which by 

 the putrefactive process, would have been converted 

 into geine. Green plants, especially those which 

 contain much starch, sugar, gum, &c., ploughed in,, 

 or placed in compost heaps, are liable to be lost in 

 this manner. This explains what had for years been 

 a puzzle to me. I once ploughed in as much green 

 cornstalks as could well be covered with soil, in the 

 month of September. And in subsequent years the 

 soil was not in the least benefitted by it. It was,, 

 doubtless, converted into alcohol, vinegar, and gases; 

 poor food for vegetables. Dried plants give more 

 geine than green — because they have parted with 

 most of their sap, and from the moment when their 

 living functions ceased, new combinations of their 

 elements began, and decay, putrefaction commenced.. 

 Dry crops, and probably those killed by frost, will, I 

 am inclined to think, be found most readily and with 

 the least loss to putrefy and form geine. There must 

 be also a great difference in different plants as to 

 their tendency to putrefy or to run into vinous or 

 acid fermentation. Here chemistry can prove the 

 only sure guide to successful experiments. There 

 is one other mode in which plants are decomposed, 

 and that is by what is termed "-^ destmctive putrefac- 

 tion.'' It is rather a slow combustion ; it is seen 

 where green plants are heaped together, and become 

 heated, so that all except their inorganic constituents 

 are literally burnt up and lost. Manure and com- 

 post heaps should never be permitted to thus run to 

 destruction — but as soon as they begin to evolve 

 steam, be spread open and cooled with water or 

 otherwise. 



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