Green-leaf Food. 



41 



These analytical results give rise to several observations : 



1. It will be seen that rape is much more nutritious than green 

 rye, and contains as large a proportion of flesh-forming constitu- 

 ents as the best kinds of food which are used in a green state. 



2. But not only is rape rich in flesh-forming matters, but it 

 contains also a considerable quantity of oily or fatty matters. It 

 will be observed that the fresh leaves contain of these fatty 

 matters more than a half per cent., and the perfectly dry substance 

 about five per cent. So large a proportion of fatty matters, as 

 far as I know, does not occur in any other green food. 



The occurrence of so considerable a quantity of fatty matters 

 explains at once, in an intelligible manner, the high fattening 

 properties which distinguish rape as a sheep-feed. 



Rape requires to be grown on good land. In poor soils it 

 never comes to anything, and it is not worth the trouble of culti- 

 vating. On land of moderate fertility, or on good rich land, an 

 occasional crop of rape, I am inclined to believe, would supply 

 the farmer with a larger amount of feeding material than is 

 afforded in a crop of turnips grown under the same circumstances. 

 Weight for weight, rape is richer in flesh-forming matters, and 

 especially in fatty substances, than turnips ; and as a crop of rape 

 per acre is often heavier than a turnip crop, the more extended 

 cultivation of rape appears to be desirable wherever it is admis- 

 sible to introduce it. 



With respect to the feeding value of green rye, it appears, 

 according to the above analyses, that it is inferior to the better 

 sorts of clover. 



White Mustard (Sinapis alba), and Prickly Comfrey (Sym- 

 phytum asperrimum). The general composition of these two kinds 

 of green food has been ascertained by me to be as follows: 



a. Composition in 100 parts. 



