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acre angle basin becomes bottom branch called carry cents clay column consider construction cost crops cultivation curves deep depth desirable discharge distance ditch drain drainage drained soil earth easily elevation embankment enter expense experience fall farm farmer field figure flat flow four give given grade ground head height hold hundred feet important improvement inches increase junction kind laid land larger length less lower machine marked matter means ment method natural necessary notes obtain outlet pass plants portion practical prairie present produce profit rain reason remove rises road roots saturated seen short shown side silt slope soil spring stake sufficient suppose surface taken things tile Tile Drain tion tubes turn vary water-table wish
第 15 頁 - An excavation was made in the field to the depth of six feet, and a stream of water was directed against the vertical wall of soil until it was washed away, so that the roots of the plants growing in it were laid bare. The roots thus exposed in a field of rye, in one of beans, and in a bed of garden peas, presented the appearance of a mat, or felt of white fibres, to a depth of about four feet from the surface of the ground.
第 89 頁 - The cross drains into which they discharge should he of ample dimensions. On these longitudinal lines of tiles the introduction of catch basins at intervals of 50 feet will facilitate the removal of the water. These catch basins may be excavated three or more feet square and as deep as the tiles are laid. After the tiles are laid the pit is filled with gravel and small stones. Fig. 13. Fall of Drains. It is a mistake to give too much fall to small drains, the only effect of which is to produce such...
第 16 頁 - Mass., and presented to the College museum by Mr. BH Averell. Prof. Stockbridge, last fall, washed out a root of common clover, one year old, growing in the alluvial soil near the Connecticut River, and found that it descended perpendicularly to the depth of eight feet. Mr. Mechi, of Tiptree Hall, England, tells us that the reason clover is usually so short-lived, is the fact that the lower roots are either unable to penetrate the subsoil or to find in it the requisite supplies of food. He also states...
第 86 頁 - ... dust, is not an adequate road for heavy traffic. Senator BANKHEAD. In my State the majority of the mileage is gravel road, that is, the improved roads. For that type of road that is untreated, the weight that Senator Byrnes spoke of is very injurious, is it not? Mr. MACDONALD. Only during the season of the year when the frost is coming out of the ground, always keeping in mind the use of pneumatic tires and the strict limit of the road. Senator WHITE. That is two months for Maine. Mr. MACDONALD....
第 16 頁 - ... depth of eight feet. Mr. Mechi, of Tiptree Hall, England, tells us that the reason clover is usually so short-lived, is the fact that the lower roots are either unable to penetrate the subsoil or to find in it the requisite supplies of food. He also states that his neighbor, Mr. Dixon, of Riven Hall, dug a parsnip which measured thirteen feet six inches in length, but, unfortunately, was broken at that depth.
第 57 頁 - If we double the grade per hundred feet of the drain we increase its carrying capacity about one-third." If this be true, then if we lower the grade by half we should decrease the carrying capacity by one-fourth.
第 16 頁 - the roots of maize, which in a rich and tenacious earth extend but two or three feet, have been traced to a length of ten or even fifteen feet in a light, sandy soil.