62 OUR FARM CROPS. 



mined mathematically that of all forms bounded by curved 

 lines, spheres are those which pack closest together, and 

 leave the smallest amount of interstices. For instance, if 

 a bushel measure were filled with round shot, that same 

 shot, if re-cast into oval (or any other) shapes, would require 

 much more space than the area of the measure that before 

 contained it. Thus, round, short, plump grains, like the Chid- 

 ham, always weigh more per bushel than the fine bold grains 

 of the Talavera variety. A smooth-skinned wheat always 

 packs closer in the measure than a rough or wrinkled 

 skinned variety (as there is less friction), and a dry sample 

 always better than a damp one, for the same reasons. In 

 the subsequent analyses of the samples experimented upon 

 by Keiset, a certain relation was invariably observed be- 

 tween the real weight (specific gravities) of the specimens 

 and their real nutritive values (the nitrogen compounds) ; 

 whereas no such deductions could be drawn from the mere 

 market weights per bushel, which were determined solely 

 by the mere shape and condition of the grains. 



Before we proceed to the next portion of our subject, 

 let us just take a glance at the different operations we have 

 described, and see how far, in a money point of view alone, 

 the application of machinery benefits the farmer in this 

 single crop. Let us compare the two types of farming 

 together; the one where the broadcast, the hand-hoe, the 

 sickle, and the flail are still retained; and the other 

 where the drill, the horse-hoe, the reaper, and steam show 

 the action of brains upon the breeches pocket : 



By drilling, J to J the seed is saved say, 1 bushel of wheat, worth 070 



By horse-hoeing, at 6d., instead of hand-hoeing, at 3s., 026 



By reaping machine, 3s. 6d., instead of hand-reaping, at 12s., ... 086 

 *By steam thrashing at 9d., instead of the flail at 3s. 5d. (4 qrs. 



peracre), 10 8 



Saving per acre by the substitution of machines for manual labour, 178 

 * From 5 to 10 per cent, more grain is got out of the straw by steam thrash- 



