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sistent—it must be sure. If without either consistency or certainty, it is 
not science but empiricism. A few modern instances are insufficient 
warrant of a principle. Science requires an age to verify its simplest 
truths—an era to achieve and substantiate its important discoveries. 
The theory of special culture and manuring is a very simple one. 
Experience shows that the plant derives its sustenance from the soil. 
Analysis discovers in the fruit the very identical properties that before 
existed in the earth. The reproduction from year to year of the same 
crop in the same field, is attended with an annual decrease in quantity, 
and depreciation in quality of the yield. By supplying the soil with the 
agents which vegetable growth has extracted from it, its productiveness 
is sustained. These are simple and practicable facts—the foundation of 
principles to the elucidation of which science has devoted the labor of years. 
The mechanical changes effected in the soil are by plowing, fallowing, 
and drainage. To turn over the surface, the bare crust of the soil, from 
year to year, is productive of little benefit. Plowing should be deep 
and thorough. It should expose to the action of the atmosphere the in¬ 
ner strength and wealth of the soil. It should effect a mixture of the 
under and compact strata, with the upper and lighter. Much of the es¬ 
sential support of the plant comes from depths to which light plowing 
does not reach. The little roots and rootlets must pierce the hard ground 
beneath, in the smaller pores of which, unexposed to the sun, necessary 
moisture is secreted. To loosen this, and bring it near the surface, is to 
relieve the plant of a great part of the labor used to reach it, which will 
then be applied to developing the mature stalk and the fruit. 
Fallowing is of great benefit as well to a strong as to an exhausted 
soil. It may not be that the soil tires in the labor of production, but, 
at least, rest revives it, and restores the fertilizing properties extracted 
by the productiveness of years. The reasons are probably various. It 
affords opportunities for clearing the land of rank and noxious weeds, 
which have burdened the soil, at the expense of virtuous and healthful 
plants. The vegetation that springs up in the absence of the crop, is 
turned under, and serves to manure the soil on which it grew. Land 
that is cropped for years loses in a great degree the properties which, 
enter into the grain, and which cannot be supplied except by natural 
means, by the process of decomposition, and by atmospheric and other 
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