108 FEEDING WITH SUGAR BEETS, SUGAR, ETC. 



placed in a revolving drum in which the sand, etc. , is separated 

 through a well-arranged sieve, and this work may be very thor- 

 oughly done even during drying. Attention is called to the fact 

 that in soil or sun-drying, the dew and rain bring about a slow 

 decomposition of the oxalic acid. This fact is new and was 

 unknown several years since; if true, it has a more than second- 

 ary importance. At first sight, it would seem impossible to 

 decrease the oxalic acid and at the same time retain the total 

 sugar in the tops and leaves, as oxalic acid needs for its entire 

 decomposition a high temperature, which would destroy the 

 sugar. Just why during sun-drying the oxalic acid should 

 decrease has never been satisfactorily explained. Is the reduc- 

 tion due to an oxidation or the action of some micro-organism ? 

 The drying means a considerable loss of oxalic acid. Before 

 desiccation the leaves contained 2. 39 per cent, of this acid and 

 after the hot-air treatment it fell to 0.60 per cent. The average 

 for all the samples examined during one week was 0.45 per 

 cent., while the analysis of a sample of the previous year showed 

 only 0.35 per cent, of oxalic acid. Under these circumstances 

 there can be no possible objection to feeding these dried leaves 

 to cattle in their regular daily ration. On the other hand, when 

 the green leaves are fed there are great risks, for the simple 

 reason that the acid percentage of the dry matter frequently 

 reaches 5.9. 



When leaves are submitted to a very high temperature, as is 

 suggested by Maercker, there is always some danger of bring- 

 ing about an alteration in the sugar which is not desirable: 

 hence the advisability of never exceeding a certain limit, and 

 this is controlled by a current of cool air and the addition of 

 some fresh substance to the mass. Both Drs. Zelber and 

 Maercker declared that by the Wusterhagen mode there is no 

 decomposition of the sugar. The operation of drying offers 

 certain difficulties in view of the fact that one has varying 

 elements to contend with, and these are all of very different 

 natures. For example, the tops have an entirely different 

 structure from the leaves, and in the latter the special delicate 

 botanical formation must be taken into consideration. If there 

 existed simply a regular, uniform heating, one portion would 



