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sufficient tests should be made before the outlay for so costly work is encountered. There is, on the other hand, much land which only by thorough-draining can be rendered profitable for cultivation, or healthful for "residence, and very much more, described as “ordinarily dry land,” which draining would greatly improve in both productive value and salubrity. The Surface Indications of the necessity for draining are various. Those of actual swamps need no description; those of land in cultivation are more or less evident at different seasons, and require more or less care in their examination, according to the circumstances under which they are manifested. If a plowed field show, over a part or the whole of its surface, a constant appearance of dampness, indicating that, as fast as water is dried out from its upper parts, more is forced up from below, so that after a rain it is much longer than other lands in assuming the light color of dry earth, it unmistakably needs draining. A pit, sunk to the depth of three or four feet in the earth, may collect water at its bottom, shortly after a rain;–this is a sure sign of the need of draining. All tests of the condition of land as to water, such as trial pits, etc., should be made, when practicable, during the wet spring weather, or at a time when the springs and brooks are running full. If there be much water in the soil, even at such times, it needs draining. If the water of heavy rains stands for some time on the surface, or if water collects in the furrow while plowingdraining is necessary to bring the land to its full fertility. Other indications may be observed in dry weather;-wide cracks in the soil are caused by the drying of clays, which, by previous soaking, have been pasted together; the curling of corn often indicates that in its early growth it has been prevented, by a wet subsoil, from sending down its roots below the reach of the sun's heat, where it would find, even in the dryest weather, sufficient moisture for a healththy growth; any severe effect of drought, except on poor sands and gravels, may be presumed to result from the same cause; and a certain wiryness of grass, together with a mossy or mouldy appearance of the ground, also indicate excessive moisture during some period of growth. The effects of drought are, of course, sometimes manifested on soils which do not require draining, such as those poor gravels, which, from sheer poverty, do not enable plants to form vigorous and penetrating roots; but any soil of ordinary richness, which contains a fair amount of clay, will withstand even a severe drought, without great injury to its crop, if it is thoroughly drained, and is kept loose at its surface. Poor crops are, when the cultivation of the soil is reasonably good, caused either by inherent poverty of the land, or by too great moisture during the season of early growth. Which of these causes has operated in a particular case may be easily known. Manure will correct the difficulty in the former case, but in the latter there is no real remedy short of such a system of drainage as will thoroughly relieve the soil of its surplus water.
The Sources of the Water in the soil are various. Either it falls directly upon the land as rain; rises into it from underlying springs; or reaches it through, or over, adjacent land.
The rain water belongs to the field on which it falls, and it would be an advantage if it could all be made to pass down through the first three or four feet of the soil, and be removed from below. Every drop of it is freighted with fertilizing matters washed out from the air, and in its descent through the ground, these are given up for the use of plants; and it performs other important work among the vegetable and mineral parts of the soil.
The spring water does not belong to the field,—not a drop of it, and it ought not to be allowed to show itself within the reach of the roots of ordinary plants. It has fallen on other land, and, presumably, has there done its appointed work, and ought not to be allowed to convert our soil into a mere outlet passage for its removal. The ooze water, that which soaks out from adjoining land,-is subject to all the objections which hold against spring water, and should be rigidly excluded. But the surface water which comes over the surface of higher ground in the vicinity, should be allowed every opportunity, which is consistent with good husbandry, to work its slow course over our soil, not to run in such streams as will cut away the surface, nor in such quantities as to make the ground inconveniently wet, but to spread itself in beneficent irrigation, and to deposit the fertilizing matters which it contains, then to descend through a welldrained subsoil, to a free outlet. From whatever source the water comes, it cannot remain stagnant in any soil without permanent injury to its fertility.
The Objection to too much Water in the Soil will be understood from the following explanation of the process of germination, (sprouting,) and growth. Other grave reasons why it is injurious will be treated in their proper order.
The first growth of the embryo plant, (in the seed,) is merely a change of form and position of the material which the seed itself contains. It requires none of the elements" of the soil, and would, under the same conditions, take place as well in moist saw-dust as in the richest mold. The conditions required are, the exclusion of light; a certain degree of heat; and the presence of atmospheric air, and moisture. Any material which, without entirely excluding the air, will shade the seed from the light, yield the necessary amount of moisture, and allow the accumulation of the requisite heat, will favor the chemical
changes which, under these circumstances, take place in the living seed. In proportion as the heat is reduced by the chilling effect of evaporation, and as atmospheric air is excluded, will the germination of the seed be retarded; and, in case of complete saturation for a long time, absolute decay will ensue, and the germ will die. The accompanying illustrations, (Figures 1,2 and 3,) from the “Minutes of Information ” on Drainage, submitted by the General Board of Health to the British Parliament in 1852, represent the different conditions of the soil as to moisture, and the effect of these conditions on the germination of seeds. The figures are thus explained by Dr. Madden, from whose lecture they are taken :
“Soil, examined mechanically, is found to consist entirely “of particles of all shapes and sizes, from stones and peb“bles down to the finest powder; and, on account of their “extreme irregularity of shape, they cannot lie so close to “one another as to prevent there being passages between “them, owing to which circumstance soil in the mass is “always more or less porous. If, however, we proceed to “examine one of the smallest particles of which soil is “made up, we shall find that even this is not always solid, “but is much more frequently porous, like soil in the mass. “A considerable proportion of this finely-divided part of * “soil, the impalpable matter, as it is generally called, is “found, by the aid of the microscope, to consist of broken • “down vegetable tissue, so that when a small portion of “the finest dust from a garden or field is placed under the “microscope, we have exhibited to us particles of every “variety of shape and structure, of which a certain part is “evidently of vegetable origin. “In these figures I have given a very rude representation “of these particles; and I must beg you particularly to “remember that they are not meant to represent by any “means accurately what the microscope exhibits, but are “only designed to serve as a plan by which to illustrate “the mechanical properties of the soil. On referring to “Fig. 1, we perceive that there are two distinct classes of “ pores,-first, the large ones, which exist between the par“ticles of soil, and second, the very minute ones, which “occur in the particles themselves; and you will at the “same time notice that, “whereas all the larger 7| “pores,-those between the o “particles of soil, - com“municate most freely with “each other, so that they “form canals, the small “pores, however freely they : “may communicate with o “one another in the interior “of the particle in which “they occur, have no direct “connection with the pores of the surrounding particles. “Let us now, therefore, trace the effect of this arrangement. “In Fig. 1 we perceive that “these canals and pores are “all empty, the soil being “perfectly dry; and the “canals communicating free- o “ly at the surface with the “surrounding atmosphere, “the whole will of course “be filled with air. If in “this condition a seed be “placed in the soil, at a, “you at once perceive that “it is freely supplied with air, but there is no moisture y “therefore, when soil is perfectly dry, a seed cannot grow.