*ON THE COMPOSITION OF GREEN RYE AND RAPE. 



BY DR AUGUSTUS VOELCKEB, 

 Professor of Chemistry in the Royal Agricultural College, Cirencester. 



IN a paper of mine on the composition of green food, which ap- 

 peared in the July number of this Journal for 1853, analyses of 

 most articles of food which are used in a green state will be found. 

 I have not stated, however, in that paper the composition of green 

 rye, as I had not an opportunity of obtaining the material for 

 analysis in a perfectly fresh condition at the time when the other 

 analyses were made. In order to supply this deficiency, I have 

 this spring submitted young rye to a detailed analysis, the re- 

 sults of which may not be without interest to the agricultural 

 reader. The analysis of rye is followed by detailed analyses, 

 both organic and inorganic, of rape. Since the publication of the 

 general composition of green rape in the paper referred to above, 

 my attention was directed by several good practical farmers and 

 sheep-breeders in this neighbourhood, to the remarkable fattening 

 properties of green rape, which, I am told, render it a most valu- 

 able food for sheep. This circumstance induced me again to examine 

 green rape. As the chief object of my previous analyses was to 

 ascertain its flesh-forming properties, direct determinations of the 

 fatty matters, and other substances which are employed in the 

 animal economy in the laying on of fat, were omitted. In the 

 subjoined proximate analyses, on the contrary, particular care was 

 bestowed on the direct and accurate determination of the fat-pro- 

 ducing constituents of green rape. At the same time, the ulti- 

 mate composition of green rape has been ascertained as well as 

 that of its ash. It is much to be regretted that we possess so few 

 detailed organic analyses of agricultural products, on the accuracy 

 of which dependence can be placed. Most analyses of this sort 

 were made at a time when organic chemistry was quite in its in- 

 fancy. The analytical processes with which chemists were then 

 acquainted necessarily were very imperfect, and consequently ill 

 calculated to furnish accurate results. More correct proximate 

 analyses of most kinds of agricultural produce are thus much 

 required. With the publication of such analyses, a clear descrip- 

 tion of the method which has been followed in determining the 

 different organic constituents should never be omitted, for the 

 publication of analytical methods will often induce others to engage 

 in similar researches. At the same time, it will tend much to the 

 suppression of analyses made by improperly qualified persons ; 

 and it may likewise lead to more accurate or simple plans of 

 operation. Before stating, therefore, the results of the analyses of 

 green rye and rape, I shall briefly describe the method which I 



