REPORT OF THE CHEMIST. 



119 



all samples which we have examined have not been taken out for sev- 

 eral mouths later. At least these results show how varied the condi- 

 tions are, and how unsafe it is to generalize from any one experiment. 

 In the analyses appended to this paper this poiut is made evident. 



As to the nature of the fermentation and the proximate principles in- 

 volved I have made some observations. In but one sample out of many 

 examined has any trace of Saccharomyces been fouud. As a rule the 

 juice expressed from the fresh ensilage is swarming with Bacillus subtilis, 

 together with some species of Bacterium and Micrococcus. No signs of 

 a viscous or lactic ferment have been observed. The fermentation does 

 not appear, therefore, to be of an alcoholic nature, or similar to any 

 with which we are well acquainted. Analyses show the presence of an 

 insufficient amount of alcohol, gum, or free acid for any of the usual 

 forms, as can be seen from the following determinations. 



Alcohol has not been found absent in any of the ensilages experi- 

 mented with, but in all was present in such small amount as to be dis- 

 tinguished only by the iodoform test. 



Lactic acid has always been detected, but never in very large amounts. 



Acetic acid is the chief acid of the ensilage. The relative proportion 

 of the two acids in the ensilage varies largely, the percentage of acetic 

 being always greater. 



Serial number. 



Lactic acid. 



Acetic acid. 





Per cent. 

 Traces. 

 .15 

 .52 

 .24 

 .26 

 .13 

 .11 



Per cent. 



2.12 

 L 59 

 .80 



Undetermined. 



1.02 



Undetermined. 



Undetermined. 



*2. 40 

 *L 22 



1004 



1500 



1501 



1502 



1677 



1693 



1540 











* Total as acetic acid. 



The whole amount present varies from one to a little over two per 

 cent., the lactic not rising above six- tenths of one per cent. 



The presence of lactic acid was determined by expressing the juice 

 from a specimen of ensilage, distilling off the volatile acetic acid by 

 repeated distillations, and neutralizing with zinc carbonate. The crys- 

 tals of zinc lactate which were obtained on evaporation were recrys- 

 tallized and analyzed. They contained — 



Constituents. 



Analysis. 



Theory. 

 (CsHsOsJaZn-j-SHaO. 





18. 46 

 26. 71 



18. 18 

 27. 27 



ZnO 





Gum or similar substances are not formed in any large amount in 

 the silo. 



Sugar unchanged from the original cane has been found in the juice 

 expressed from two ensilages, but as a rule it completely disappears. 

 No. 1003 contained 2.40 per cent., No. 1004 1.07 per cent., and No. 1541 

 .76 per cent, of reducing sugars. The fiber is, of course, increased in 

 relative amount, but absolutely it probably is but slightly altered. 



In the following table analyses of a number of ensilages are presented 

 together with those of a dried fodder, and several green stalks at va- 

 rious stages of development. From them much may be learned as to 

 the variations to be expected. 



