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adapted to retain moisture, and others to repel it. Do not these facts 
point out an unmistakable adaptation between the manure and the crop, 
as plainly as was before seen between the soil and manure. 
Soil is composed of disintegrated mineral substances—(mineral is here 
and elsewhere used in its geological significance)—ard partakes of the 
nature of its original. If the rock was quartz, the soil will be sandy ; if 
feldspathic or micaceous,* the soil will be clay or loam, if both are inter¬ 
mixed. But soil, as we now find it, rarely is thus simple in its composi¬ 
tion, containing also humus or decayed vegetable matter, which is chiefly 
composed of carbon, (seventy-five per cent), and alkaline elements as 
lime (formed from the disintegration of carbonate of lime, which can easily 
be tested with acid) and potash, which exists in both Feldspar and Mica. 
In a general analysis of soil, the first object of enquiry is, to ascertain 
the proportion of sandy matter, which can be done by washing the cal¬ 
cined soil; and secondly, to find the proportion of clay and other solu¬ 
ble substances, which is also found by washing the soil and filtering; and 
thirdly, to find the proportion of humus, which may be tested with suf¬ 
ficient accuracy by noticing the loss in waste by calcination, f 
An examination of a more general nature may be based on the above, 
by considering soils with reference : 
1st. To their specific gravities. 
2d. Their capacity for holding water. 
3d. Their aptitude to yield moisture. 
4th. Their faculty for acquiring and retaining heat. 
[Note. —By following this examination with a study of the peculiar nature 
of different manures, and the habits of crops, we shall be able to arrive at defi¬ 
nite conclusions, and know as facts worthy of confidence what we would other¬ 
wise follow as conjecture; and agriculture would, even to the farmer, be reduced 
to a science, which would be governed by fixed and natural laws, and follow 
rules unalterable because fundamental, instead of being the sport of circum¬ 
stances or the slave of the prejudices of ignorance. Farmers are themselves 
culpably negligent in the performance of their duty; they act as though they 
were only machines to raise produce, and exchange that produce for cash or the 
necessaries of life. Let them cultivate a spirit of inquiry, as well as the soil, 
and raise their thoughts to the consideration of the principles that govern the 
stupendous changes that are constantly taking place before their eyes.] 
* Feldspar contains nearly twenty and Mica thirty-four per cent, of Alumina. 
t The soil should be perfectly dry before it is first weighed. 
i 
