. Elementary principles of agriculture; a text book for the common schools . B in a glass of water, a second dozen in w^et sand, and a third dozen in slightly damp sand. Examine every day, and judge the amount of water absorbed, by the in- creased size and weight of the seeds. 24c. Rate of Ab- sorption Affected by the Number of Points of Contact. Take two lots of seeds, corn for ex- ample, and place each lot in a tumbler or other vessel with the same amount of moist sawdust. In one, sprinkle a layer of sawdust, and then a layer of seeds, then another layer of each, taking care that in one the
. Elementary principles of agriculture; a text book for the common schools . B in a glass of water, a second dozen in w^et sand, and a third dozen in slightly damp sand. Examine every day, and judge the amount of water absorbed, by the in- creased size and weight of the seeds. 24c. Rate of Ab- sorption Affected by the Number of Points of Contact. Take two lots of seeds, corn for ex- ample, and place each lot in a tumbler or other vessel with the same amount of moist sawdust. In one, sprinkle a layer of sawdust, and then a layer of seeds, then another layer of each, taking care that in one the saw-dust is not pressed down, but kept very loose. Prepare the second vessel just as above, but press the sawdust firmly around the seeds. This increases the number of points of contact between the sawdust and the seeds. Cover, to prevent drying out, and examine the seeds at the end of every twelve hours. Does pressing the saw-dust about the seeds make them swell more quickly? 24d. Prompt Absorption Hastens Germination. Sow some peas in a gardener's flat, filled with very loose sawdust. Press the sawdust Fig. 14. A, a young root of the pea marked with fine lines of water- proof ink into 13 spaces. B, the same root, 24 hours later, showing elongation only in terminal 5 spaces. The rate of growth is greatest in the second and third spaces and slow in the first, fourth and fifth. Magnified 2 diam; C, tip of root greatly magnified and shown in section . w, root-cap; i, younger part of cap; i, dead cells separating from cap; s, growing point; p, central cylinder.
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Keywords: ., bookauth, bookcentury1900, bookdecade1900, booksubjectagriculture
