NATURE AND VALUE OF FOOD. 43 



crops contain, as a rule, very little sugar, the lactic fermenta- 

 tion does not take place to any extent, but as soon as 

 fermentation begins, alcohol is formed, which means a loss of 

 nutritive matter, and this is intensified by the almost immediate 

 conversion of the alcohol into aldehyd, and when this exists a 

 very considerable loss of feeding material occurs. Our readers 

 will recognise this material as the same produced in over-heated 

 hay. Lastly, if the fermentation goes farther, the aldehyd is con- 

 verted into acetic acid. It is probable that the most important 

 effect of fermentation is on the woody fibre, which is rendered 

 more digestible by the process. Now it is quite evident that 

 great care is required to ensure proper fermentation, and that 

 any mismanagement must result in serious loss, and Mr. Jenkins, 

 in his valuable paper, vol. 20 E. A. S. E., new series, says : 

 " In the case of our own fodder crops, the evidence given in the 

 foregoing pages tends to show that crops cut before they begin 

 to get woody (in other words, while they are still full of sap), 

 pitted after having been chopped, then carefully trodden layer 

 by layer, then covered with boards, and moderately weighted, 

 stand the best chance of not going much beyond the alcoholic 

 fermentation. On the other hand, crops put in unchopped, 

 dripping with wet, imperfectly trodden, and no matter how 

 heavily weighted, will rapidly go through all the processes, and 

 even beyond those I ha.ve spoken of, namely, into the putre- 

 faction stage." Mr. Jenkins suggests that the chemists will, by 

 their investigations, be able to give us a Dr. and Cr. account as 

 between the loss of feeding material by the conversion of carbo- 

 hydrates into alcohol and acetic acid on the one hand, and the 

 gain of feeding material by the conversion of indigestible into 

 digestible woody fibre on the other. In the meantime the 

 practical testimony as to the wholesome and nutritious character 

 of well-made silage is simply overwhelming, and especially as 

 regards milk production ; there is every reason to believe that 

 it compares very favourably with the same material made into 

 hay. We rather agree with Mr. Jenkins in regarding the 

 system of ensilage as a valuable addition to the resources of the 

 English farmer, rather than a complete substitute for hay- 

 making. Within the last two or three years much light has 

 been thrown on the subject by the experiments of Mr. Geo. Fry, 



