. How crops grow. A treatise on the chemical composition, structure and life of the plant, for students of agriculture ... Agricultural chemistry; Growth (Plants). ELEMENTS OF ORGANIZED STRUCTURE. 245 apple or tomato, we are able, by means of a low magni- fier, to distinguish the cells of which it almost entirely consists. Fig. 28 represents a bit of the flesh of a ripe pippin, magnified 50 diameters. The cells mostly cohere together, but readily admit of separation. • Structure of the Cell.—By the aid of the micro- scope it is possible to learn something with regard to the internal structure
. How crops grow. A treatise on the chemical composition, structure and life of the plant, for students of agriculture ... Agricultural chemistry; Growth (Plants). ELEMENTS OF ORGANIZED STRUCTURE. 245 apple or tomato, we are able, by means of a low magni- fier, to distinguish the cells of which it almost entirely consists. Fig. 28 represents a bit of the flesh of a ripe pippin, magnified 50 diameters. The cells mostly cohere together, but readily admit of separation. • Structure of the Cell.—By the aid of the micro- scope it is possible to learn something with regard to the internal structure of the cell itself. Fig. 29 exhibits the appearance of a cell from the flesh of the Artichoke (Helianthus), magnified 330 diameters; externally the membrane, or wall of the cell, is seen in section. This membrane is filled and distended by a transparent liquid, the sap or free water of Tegetation. Within the cell is ob- -6 served a round body, i, which is called the nucleus, and upon this is seen a smaller nucleolus, c. Lining the inte- rior of the cell-membrane and connected with the nucleus, is a yellowish, turbid, semi-fluid substance of mucilaginous consistence, a, which is designated the protoplasm, or formative layer. This, when more highly magnified, is found to contain a vast number of excessively minute granules. By the aid of chemistry the microscopist is able to dis- sect these cells, which are hardly perceptible to the unassisted eye, and ascertain to a good degree how they are constituted. On moistening them with solution of iodine, and afterward with sulphuric acid, the outer membrane—the cell-wall—shortly becomes of a fine blue color. It is accordingly cellulose, the only vegetable substance yet known which is made blue by iodine after, and only after, the action of sulphuric acid. At the same time we observe that the interior, half-liquid, pro- toplasm,, coagulates and shrinks together,—separates, therefore, from the cell-wall, and, including with it t
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectagriculturalchemistr
