10 VOELCKEK on the Chemistry of Food. 



shall now proceed by directing attention to the composition 

 of the principal varieties of feeding-stuffs which are used by 

 the British farmer either for rearing or fattening of stock. 



1. LlNSEED. According to Anderson, linseed contains in 100 

 parts : 



Moisture 7*50 



Oil 34-00 



Nitrogenized or flesh-forming constituents .. .. 24'44 

 Substances not containing nitrogen 



Heat-producing principles 30 '73 



Mineral matters (ash) 3'33 



The ash of linseed is rich in phosphates or in bone-materials. 

 It will be observed that linseed is both very rich in ready-made 

 fat and in muscle-producing substances. Linseed, for these 

 reasons, is admirably well adapted both for young growing stock 

 and fattening beasts. There is, indeed, hardly any other feeding 

 substance which equals linseed in nutritive power. Whether it 

 is superior to good linseed-cake or not is a point on which there 

 seems to exist some diversity of opinion among practical feeders. 

 Good oil-cake, we shall see presently, contains a larger amount 

 of flesh-forming principles, and may therefore be better adapted 

 to feeding when it is wished rather to produce muscle than to lay 

 on fat. For fattening beasts, I am decidedly of opinion linseed 

 is preferable to cake, for it contains a much larger proportion of 

 ready-made fat than cake, and the oils and other constituents of 

 linseed have not undergone those changes to which they are so 

 liable in the preparation of linseed-oil and cake, especially if heat 

 is employed in the manufacture of the latter. Whilst linseed is 

 always free from any rancid oil, and consequently possesses a 

 sweet, agreeable taste, the oil still remaining in the cake is often 

 so rancid that the cake becomes unpalatable to beasts. In lin- 

 seed, moreover, the albuminous substances and the mucilage exist 

 in a more soluble condition than in cake ; heat, which renders 

 these substances less soluble, being generally employed in the 

 extraction of the oil from the seed. Linseed thus is more easily 

 digested than cake a circumstance of considerable importance 

 in estimating the nutritive value of both. 



Made into a jelly, linseed is often given to weaned calves, who 

 are very fond of it, and get on upon it remarkably well. Linseed- 

 jelly, mixed with chaff, meal, and sliced turnips, is also recom- 

 mended by practical feeders as one of the best mixtures that can 

 be given to fattening beasts ; and for the preparation of this 

 well-known mess many prefer linseed to the cake. 



In using linseed for feeding or fattening purposes, however, 

 care ought to be taken not to allow too large a proportion of seed 

 to the animals, inasmuch as linseed-oil exercises, when given in 



