1020 Agricultural Gazette oj N.S. W. [Dec. 2, 1908. 



The lirst of these liyjii>tlit--es may l)e dismissed at once, since silage 

 invariably contains l)actei-ia and is never sterile. Bacteria must, therefore, 

 obviously plav some pai-t, even if only a secondary part, in the process. Tt is 

 equally clear that the liviiii;- cell is an active agent. Silage is always made 

 from living plants, and the cells live for some time after they are put into 

 the silo; the Itreaking down ]irocesses can stilly go on, though they may he 

 nuxHHed bv the absence of air, l)ut the building-Qp })rocesses depending on 

 light and air are stopped. Thi'ee sets of agents — the living protoplasm, 

 •enzymes and bacteria — a[)peai- to l)e involved, and no hypothesis is satis- 

 factorv \\ Inch fails to take account of all three. 



The green maize and the silage dealt with in the present paper wei-e produced 

 at the Wye Agricultural College, where a large part of the experimental work 

 was done. The method of making the silage is described in the precerling 

 paper; the details of the separation and the analytical results ai-e in the 

 experimental ])ai^t of the pi-esent one. 



The substances produced during ensilage. 



On comparing the weights of the various groups of constituents of gi-een 

 maize put into the silo with those (»f the silage brought out, it is found 

 (see article, "The Composition of Green Maize," itc.) that (1) there has Ijeen 

 practically no change in the fibre; {-) all of the sugar and some of the less 

 resistant celluloses disappeai^ ; (3) carbonic acid is evohcd and a niimliei- of 

 acids appear, which were not before present; (4) the "protein'' niti^ogen 

 compounds, i.e., those forming insoluble compounds with copper hydrate, are 

 reduced to about one-half ; (•")) the non-protein nitrogen compounds, i.e., those 

 forming soluble copper compounds, practically double in amount. 



The changes undergone by the nitrogenous compounds are well seen in tiie 



juices pressed outfrom maize andfrom silage respectively ; the latter contains 



more substances reacting with nitrous acid and with j)hos])hotungstic acid 



than the former. 



Relative weights, 

 Weights in 100 c. c. of juice. total N. = 100. 



Total nitrogen 



N. liberated by H.N.0.,1 ... 



N. precipitated l)y phospho- 



tungsticacid -0108 "OOO 16 37 



The relative amounts of the different groups of nitrogen conqiounds in 

 silage vary somewhat, but the juice referred to in the [(receding table con- 

 tained in 100 c.c: — 



Nitrogen as ammonia 

 Xitrogen as amide... 

 ^'itrogenas amino-acid ... 

 Nitrogen not accounted for 



100. 



Total -161 100 



^ In the apparatus designed by Drs. Brown and Millar (Trans. Guinness Research Lab. 

 1903, I, 30). 



