230 ALCOHOL, VINEGAR, SAUER KRAUT, TOBACCO, SILAGE, FLAX. 



The extent of this rise is dependent upon the amount of oxygen 

 present and the readiness with which the heat is radiated. The 

 temperature should not rise above 150 F., and, to give the best 

 result, it should be much lower. The proper production of silage, 

 however, does not appear to be dependent upon this rise in tempera- 

 ture, inasmuch as perfectly normal silage may be made in small 

 vessels where hardly any rise in temperature is noticeable. 



This high temperature lasts a few days and then the mass slowly 

 cools. The production of heat appears to be very rapid for a few 

 days, and then somewhat quickly declines; but a less rapid evolution 

 of heat continues for a long time, perhaps several weeks. After 

 the reduction in temperature other changes begin, which are much 

 slower, and after several weeks the character of the material is 

 found to be greatly changed. This is a secondary fermentation. 

 of a different type. It develops a certain amount of acid, its chemical 

 nature is altered, and it develops a new flavor and aroma which should 

 be distinctly aromatic, without any signs of putrefaction or mustiness. 

 There is found to be a considerable loss of material, a loss ranging 

 from 4 per cent: to 40 per cent. This is a very wide range, and 

 shows that the method of ensilage has an extraordinary effect upon 

 the product obtained. The loss is chiefly a loss of carbohydrates, 

 although there is also an appreciable loss of albuminoids. The 

 loss is largely parallel to the amount of oxygen that finds its way 

 into the silo, being very slight if the oxygen of the air be thoroughly 

 excluded. Perfect exclusion of air is, then, the best means of 

 preventing the loss. 



In a properly prepared silo the fermentative changes do not ex- 

 tend beyond this, and the material will now remain sweet for 

 months. The superficial layers may become decayed and ruined, 

 but the central mass itself is not affected. After the feeding from a 

 silo is commenced its contents must be used up somewhat rapidly, 

 for various undesirable fermentative changes may set up in the 

 superficial layers as they are successively exposed to the air. 



The Causes of Ensilage Fermentation. Three different 

 factors have been suggested as causes for the fermentations inside 

 the silo. These are: i. The action of bacteria. 2. Respiratory 



