CHEMISTRY OF CROP. 263 



with wheat-flour, for bread-making ; and a white variety, 

 round and plump in shape, is largely cultivated for use 

 for culinary purposes. It is essential that these should 

 be good boilers, 1 so as to "melt," as it is termed, readily, 

 and assume a semi-fluid or plastic condition. In Scotland 

 peasemeal is very generally consumed, by the rural popula- 

 tion especially, either mixed with oat, barley, or sometimes 

 wheat meal, in the form of bannocks or cakes, or else as 

 an ingredient in the broth that forms part of their daily 

 food. For cattle -feeding, peas are equally valuable as 

 beans. To pigs they are frequently given whole, though 

 it is much more advantageous to give them in the shape 

 of meal, mixed with some other kind of food richer in 

 fat-forming materials, as peas or beans given alone are 

 apt to give a firmness and hardness to the flesh, which 

 for food-purposes is not desirable. 



The straw has not been subject to such a rigid investi- 

 gation as the seed ; indeed, our knowledge of the action 

 of particular feeding substances upon the economy of the 

 lower animals is too imperfect to render the rigid investi- 

 gation of substances supplied only to them so necessary 

 as when they enter also into the food of ourselves. The 

 analyses, however, of Sprengel, Hertwig, and Boussingault, 

 make us sufficiently acquainted with its composition to 

 recognize at once its great value for all fodder purposes. 

 Its average composition is thus given: 



Nitrogen compounds (flesh-formers), 12'55 



Compounds not containing nitrogen, 47'52 



Compounds suitable to support respiration, and to lay on fat, 21 '93 



Water, . * 12-00 



A sh (mineral matter, suitable to the formation of bones, cartilage, &c.). 6'00 



ioo-oo 

 The correctness of these several analyses is confirmed 



1 It is said that the addition of a small proportion of soda to the water in 

 which they are boiled, will cause the "bad boilers" to become soft. This 

 would tend to point to the " legumine," rather than the sulphate of lime, being 

 the cause of difference in the boiling properties of peas. 



