Soils and crops of the farm . is covered by a light, colorless,spongy envelope composed of ceUulose, which is theprincipal ingredient in wood Eind straw. The en-velope is about three per cent, of the entire berry andis almost, if not quite, indigestible. BotanicaUy it isnot a part of the seed proper, but is equivalent to thepod of the bean or the shell of the hickory nut. Within this envelope is the testa, or true cover-ing of the seed, which is finer but similar in structure,except instead of being colorless its cells are filledwith two coloring matters, one a pale yellow and theother an oran
Soils and crops of the farm . is covered by a light, colorless,spongy envelope composed of ceUulose, which is theprincipal ingredient in wood Eind straw. The en-velope is about three per cent, of the entire berry andis almost, if not quite, indigestible. BotanicaUy it isnot a part of the seed proper, but is equivalent to thepod of the bean or the shell of the hickory nut. Within this envelope is the testa, or true cover-ing of the seed, which is finer but similar in structure,except instead of being colorless its cells are filledwith two coloring matters, one a pale yellow and theother an orange yellow. These pigments give to theberry its color, vrhich varies according to the .relativeabundance of the two. The testa is about two percent, of the berry. It is the portion which givesmillers so much trouble, as a surprisingly smallamount makes the flour dark and the bread two envelopes described constitute the bran andtogether make about five per cent, of the wheat. The 108 THE SOILS AND CBOPS OF THE liONGiTuDiNAi, Skction OF WHEAT Bebbt—(After Chester)(Highly magnified.) WHEAT. 109 bran of commerce contains sbont 75 per cent, of othermaterials; that is to say, 15 per cent, of the natritiveportion of wheat; otherwise bran would be practicallyvalueless as a food for stock. Within these envelopes, and next to them, is a rowof irregular, cubical cells. This row of cells is sup-posed to be simply an expansion of the embryo andhas been called the embryonic envelope. The cellsare filled with phosphate of lime, and a solvent sub-stance called cerealine, which assists in germination. The body of the grain or endosperm consists of largethin-walled cells, filled mostly with starch but contain-ing also gluten and other albuminous material. Thisis the portion from which flour is made and is 75 to80 per cent, of the whole berry. In the modem pro-cesses of milling, besides the bran proper, the germ orembryo, the embryonic envelope and seven per cent,or more of the
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectagriculture, bookyear
