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The specific gravity of Soils varies in direct proportion to tlie amount 
of sand they contain, and is easily determined by the process described 
above. Clayey soils, although called heavy soils, are specifically lighter 
than sandy soils. 
The power of absorbing moisture varies in direct proportion to the 
quantity of humus contained in the soils. Humus possesses this faculty 
in a remarkable degree, one hundred parts absorbing one hundred and 
ninety of water, while clay absorbs but fifty. 
Note.— Here we see a powerful auxilliary to the farmer in preventing drought 
—Manure. Let the soil be well fed with vegetable manure, and the light rains 
and dews will all be hnsbanded and garnered up for future use in time of need, 
instead of passing at once into the subsoil.] 
The faculty of yielding Moisture— The power of retaining moisture 
sufficient to ensure vegetation is necessary, but not more so than is the 
ability to yield the excess. Soils which retain moisture too strongly are 
wet, late, and cold, while those which yield it too readily are apt to suffer 
from dry weather. Humus heads the list for its retentive properties, 
while silicious and calcareous sand possess the greatest evaporative 
power. 
The faculty of acquiring and retaining Heat depends greatly on the 
conducting power of the soil, and therefore on its density, or specific 
gravity. Soils which are quick to receive warmth are called early. Sand 
possesses this power in the highest degree, and clay in the lowest; there¬ 
fore the former are early, the latter late. 
Besides these points of investigation, based on the three primitive 
points of analysis, there are other considerations which should not be 
overlooked, such, for instance, as 
The Depth of Soil —Which is one of the most important considerations 
in husbandry, has been too much overlooked; and farmers cultivate only 
a very shallow layer of earth, which can easily be recognized by the in¬ 
termixture of humus, and the lighter color of the subsoil. There are 
several reasons why soil should be worked deep. First, We derive a 
greater advantage from the soil, for the roots can extend themselves more 
widely; and secondly, The humus intermingled with the soil to a con¬ 
siderable depth will retain the moisture, and the soil will be enabled to 
withstand the drought to which, in this country, we are liable. It is also 
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