Book VI. WHEAT. 755 



no great deviation from Professor Thaer's general estimate, a bushel of wheat weighing 

 about six or six and a half cwt. 



4642. Tojudgeof a sample of wheat, examine by the eye whether the grain be perfectly 

 fed or full, plump and bright, and whether there be any adulteration proceeding from 

 sprouted grains, smut, or the seeds of weeds ; and by the smell, whether there be any 

 improper impregnation, and whether it has been too much heated in the mow, or upon 

 the kiln ; and finally, by the feel, to decide if the grain be sufficiently dry, as when 

 much loaded with moisture it is improper for the uses of the miller and baker. In cases 

 where a sample handles coarse, rough, and does not slip readily in the hand, it may be 

 concluded not to be in a condition either for grinding or laying up for keeping. 



4643. The yield of wheat injlour is, on an average, thirteen pounds of flour to fourteen 

 pounds of grain. In the chemical analysis of wheat, Sir Humphry Davy found that 

 one hundred parts of good full-grained wheat, sown in autumn, yielded of starch seventy- 

 seven, and of gluten nineteen. One hundred parts of wheat sown in spring, seventy of 

 starch, and twenty-four of gluten. American wheats he found to contain more gluten 

 than the British ; and in general the wheat of warm climates he found abounded more 

 in gluten and in insoluble parts, and of greater specific gravity, harder and more difficult 

 to grind. 



4644. The uses of wheat in the baking, culinary, and confectionary arts are well known. 

 It is also used for making starch, by steeping the grain and then beating it in hempen bags. 

 The mucilage is thus mixed with the water, produces the acetous fermentation, and the 

 weak acid thus formed renders the mucilage white. After settling, the precipitate is 

 repeatedly washed, and then moulded into square cakes, and kiln dried. In drying the 

 cakes separate into flakes, as in the starch of the shops. Starch is soluble in hot water, 

 but not in cold ; and hence, when ground down, it makes an excellent hair-powder. 

 Its constituents are; carbon, 43*55; oxygen, 49*68 ; and hydrogen, 6*77 = 100. 



4645. The uses of wheat- straio are various, and well known : as fodder it is, according 

 to Professor Thaer, the most nourishing of any ; and it makes the best thatch : it is 

 generally preferred for litter, though rye and barley-straw are softer ; it is used for 

 making bee-hives, horse-collars, mattrasses, huts, boxes, baskets, and all kinds of what 

 is called Dunstable work ; for the cider press, and, among other things, for burning, to 

 procure potash form the ashes. The straw of wheat, from dry chalky lands, is manu- 

 factured into hats both for men and women. For this purpose, the middle part of tho 

 tube, above the last joint, is taken, and being cut into a length of eight or ten inches, is 

 split in two. These splits are then plaited, by females and children, into various kinds 

 of plait or ribbands, from half an inch to an inch broad : these, when sewed together ac- 

 cording to fancy or fashion, form different descriptions of ladies' bonnets, and the com- 

 moner plait and coarser straw of mens' hats. The hats are whitened by being placed 

 in the vapor of sulphur. Leghorn hats are made from the straw of a bearded variety of 

 wheat, which some have confounded with rye. It is cultivated on the poorest sandy 

 soils in the neighborhood of the Arno, between Leghorn and Florence, expressly for 

 this manufacture. It is of humble growth, and not above eighteen inches high ; is 

 pulled up when green, and bleached white, by spreading and watering on the gravelly 

 banks of the Arno. The straws are not split ; but in other respects the manufacture 

 into ribbands is the same as at Dunstable in England. 



4646. The diseases of wheat are the rust, smut, or black mildew, the latter including 

 what is vulgarly called blight. These have been already treated of in our view of the 

 vegetable economy, and we shall merely offer a few practical observations on the smut 

 and mildew. In whatever manner the smut may be transmitted from the seed pickle in 

 the ground to the ear, it seems certain that, in general, the proximate cause of smut is 

 the infection of the seed by the dust of the smut-ball {Lycoperdon globosum); and that, 

 though the most careful washing, even with the application of caustics, may not, in every 

 case, insure against smut ; yet, if the seed be prepared in the way already mentioned, 

 the disease will never prevail to such a degree as to effect materially the value of the 

 crop. This is all that cultivators need to know, and all, perhaps, in the present state ot 

 science, that can be known, of the cause and prevention of smut. 



4647. iV/7rfru is a much more destructive distemper than smut, and, as it is probably occasioned by a 

 pecuhar state of the atmosphere during the periods of flowering and ripening, Mt is Hkely to baffle all at 

 tempts at prevention. The prevalence of heavy fogs, or mist, drizzling rains and sudden changes in the 

 temperature, have been assigned as the causes of mildew ; and as it has been found, that open airy expo- 

 sures are much less affected than low sheltered lands, in years when mildew prevails most generally, the 

 disorder may perhaps be somewhat diminished by drilling, which admits a freer circulation of air. 

 Spring or summer wheat is less liable to mildew than the winter species, though it does not always escape. 

 Minute parasitical fungi are commonly detected on the straw of mildewed wheat ; and there cannot be the 

 least doubt that the barberry bush and probably several other shrubs, on which these fungi abound, have 

 a j)Owerful influence in communicating the disease to a certain distance. {Sir Joseph Banks on Mildew, 

 and Com. to the B. of Agr. vol. vii.) 



4648. The culture of summer wheat dilTers from that of winter or spring-sown winter 

 wheat, in its requiring a more minutely pulverised and rather richer soil. It need not 



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