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Show I i FACTS ABOUT SOILS. J. W. Mills. Did it ever occur to you that the soil breathes just as plants and ant nuils do? It is a fact that it docs. Every time it rains ot the land is irrigated, ir-rigated, it exhales and when it loses its moisture it inhales. Aside from this it has less profound breathing exercises continually. The act of water penetrating the soil expels the air and as the water penetrates an 1 leaves spaces between the soil parti-1 parti-1 clcs the air rushes in and takes its j place. This fresh air aids the plants m by making available a little mors 1 plant food and driving out the obnox- J ious gases that collect during the act . of plant growth. When water is applied to clay soils much of it will stand on the surface till evaporated instead of sinking in and being held in reserve for future use. Manure will improve this condition condi-tion as will sand. Sandy soils, on the other hand, arc improved by having ' clay added to them. It has been demonstrated dem-onstrated that in this respect, humus JBHnMHHHHMMBMMMiinBMnMBaMIIMHHfcJi is ten times more efficient than clay This physical improvement in these two types of soil may make the difference dif-ference between sterility and fertility Sand will absorb and retain about 15 per cent of its bulk of moisture while peat will absorb 70 to 80 per cent. This shows that the more hit " nuts a soil contains, the greater will be its absorbing and retentive powers. The capillarity of soils deals with the power of water to travel around or through it in any or all directions, but it is generally referred to as the power to ascend. There arc no tube formed in the soil through which tha moisture ascends -as is generally supposed. sup-posed. It is simply the power of gravity and the power known as tension. ten-sion. When two corks of different sizes arc floating in a tub, they will come together with a bump if they arc allowed al-lowed to come within a certain distance dis-tance of each other, or they wi.l bump up against the side of the tub. This is because they arc attracted by the larger body. It is the same force that makes chips collect and cling to gcther in a pool. In the case of water or other liquids, the force known as tension compels the fluids to spread over the surface. This is why the water extends up the sides of a glass to a slight degreeand on the in-!dcs in-!dcs of a glass tube to a greater degree. de-gree. It is well illustrated in . the case of a soap bubble when the stem of the pipe is removed from the mouth before the bubblie parts. In this case the tension of the liquid squeezes the air out through the pipe - stem till the bubble forms a diaphratn across the bulb of the pipe. Now these two forces, gravity and tension, force the water from one particle par-ticle of soil to the other, in all directions. direc-tions. If the soil particles arc held far apart, the moisture must travc' slowly. Cultivation loosens the soil and brings this condition ' about. When the particles settle together which they arc always doing, capillary action is faster and we must cultivate soon or we will lose more moisture. |