How crops growA treatise on the chemical composition, structure, and life of the plant, for all students of agriculture .. . ar willbe converted into a syrup by withdrawingwater from the flesh of the carrot. At thesame time the latter will visibly shrink fromthe loss of a portion of its liquid contents. Inthis case the small portions of juice moisteningthe cavity form a strong solution with thesugar in contact with them, into which water diffuses fromthe adjoining cells. Doubtless, also, sugar penetrates theparenchyma of the carrot. In the same manner, sugar, when sprinkled over thin-skinned f
How crops growA treatise on the chemical composition, structure, and life of the plant, for all students of agriculture .. . ar willbe converted into a syrup by withdrawingwater from the flesh of the carrot. At thesame time the latter will visibly shrink fromthe loss of a portion of its liquid contents. Inthis case the small portions of juice moisteningthe cavity form a strong solution with thesugar in contact with them, into which water diffuses fromthe adjoining cells. Doubtless, also, sugar penetrates theparenchyma of the carrot. In the same manner, sugar, when sprinkled over thin-skinned fruits, shortly forms a syrup with the water whichit thus withdraws from them, and salt packed with freshmeat runs to brine by the exosmose of the juices of theflesh. In these cases the fruit and the meat shrink as aresult of the loss of water. Graham observed gum tragacanth, which is insoluble inwater, to cause a rapid passage of water through a mem-brane in the same manner from its power of imbibition,although here there could be no exosmose or outwardmovement. The application of these facts and principles to explain-. CAirSES OF THE MOTION OF JUICES. 359 ing the movements of the liquids of the plant is cells and the tissues composed of cells furnish pre-cisely the conditions for the manifestation of motion hythe imbibition of liquids and by simple diffusion, as -well asby osmose. The constant disturbances needful to main-tain constant motion are to be found in fully adequate de-gree in the chemical changes that accompany the process-es of nutrition. The substances that normally exist in thevegetable cells are numerous, and they suffer remarkabletransfonnations both in chemical constitution and in physi-cal properties. The rapidly diffusible salts that are pre-sented to the plant by the soil, and the equally diffusiblesugar and organic acids that are generated in the leaf-cells,are, in part, converted into the sluggish, soluble colloids,soluble starch, dextrin, alb
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Keywords: ., bookcentury1800, bookdecade1860, booksubjectagricul, bookyear1868
