154 BRITISH HUSBANDRY. [Ch. X. 



difficult to form any acreable estimate of the amount. On soils of average 

 quality, in ordinary seasons, and under the common course of management, 

 it may, however, be fairly calculated at three quarters, or perhaps 28 

 bushels per Imperial acre. To produce the latter quantity, circumstances 

 must, however, be favourable, and anything beyond that may be considered 

 large ; though, on some land, four to five quarters are not unusual, and we 

 have lately heard of a crop in Warwickshire amounting to rather more than 

 60 bushels per acre, of clean screened corn of superior quality. The weight 

 may average 60 lbs. per bushel. 



The straw is generally reckoned to be about double the weight of the 

 grain ; an acre, producing three quarters of wheat of the ordinary quality, 

 may therefore be presumed to yield about 26 cwt. 



The use to which the grain is applied is almost exclusively that of food 

 in its various preparations, and chiefly in that of bread, though a consider- 

 able quantity — but generally of an inferior or damaged kind — is employed 

 in the manufacture of starch. This preference is due not only to th.e supe- 

 riority of its nutritive properties, but also to their peculiar nature ; for 

 •' more water is consolidated in bread made from barley, and still more in 

 that from oats ; but the gluten in wheat, being in a much larger quantity 

 than in any other grain, seems to form a combination with the starch and 

 water, which renders it more digestible than any other*." 



From a careful analysis made by Sir Humphry Davy, it was found that 

 the quantities of nutritive matter afforded by 1000 parts of wheat of different 

 qualities, were — 



Middlesex wheat of average quality 



Polish 



North American . . . 



Thick-skinned Sicilian . . 



Tliin-skinned ditto , . 



English spring-wheat . • 



From which it has been concluded by Sir Joseph Banks, — " that bread 

 made of the flour of spring-wheat is more nutritious than that from winter- 

 wheat, because spring-wheat contains a larger quantity of gluten, or half- 

 animalized matter ; and also, that a miller ought not to deduct from the 

 price of spring-wheat more than 2 per cent, on the money price of winter- 

 wheat of the same weight, as the excess of insoluble matter, or bran, is no 

 more than 2 per cent, when compared with good English wheatt." This, 

 although the reasoning of a man of ability, however, only serves as an addi- 

 tional proof that mere scientific knowledge, when unaccompanied by 

 practical experience, can never be relied upon by farmers; for it is well 

 known that the qualities of all grain vary according to the soil upon which it 

 is "rown, and the manure with which it is nourished, and that wheat when 

 dressed with stable-dung, or particularly if folded with sheep, contains the 

 largest portion of gluten : any general rule of this kind can therefore be 

 only regarded as an unsupported theory. 



FLOUR. 



The^^owr of wheat which is cut before it is quite ripe is whiter than 

 that which is allowed to come to maturity, and bears a higher price in the 

 markets. The grain which is intended for the miller should therefore be 

 reaped before it has reached its perfect gowlh ; but that which is meant 



* Lectures on Agricultural Chemistry, Icct. iii., p. 121. 



-j- Communications to the Board of Agriculture, vol. v, art. viii., p. 281. 



