I have read your essay, addressed to the Agricultural Society of Albermarle, as I have all your productions, with much pleasure and profit. Tho’ it has a particular referrence to the local circumstances in the agriculture of that particular District, it abounds with general principles applicable and important every where, recommended by the charm of your peculiar style.

As your Essay will be extensively read, & followed, I take the liberty of suggesting for your reconsideration whether you have not fallen into one mistake. And if a mistake one that may lead to too low, an estimate of the advantages of what is called the new-husbandry, & to a neglect of that great resource for improving the fertility of land.

You represent, the Theory of Tull1 as a System of incessant cropping by means of incessant tillage. I do not so understand it. I understand it to be a system of alternate cropping & fallow. The soil of the intervals between the rows of wheat or other grain is fallowed and these fallows receive the seed for the next crop, & the stubble of the former crop becomes the interval and is fallowed, in its turn, & so on alternately.

Our tobacco & indian corn cultivation are not parallel modes of husbandry. The roots of these plants occupy the whole ground, & draw nutriment from the whole, & tho’ every part is tilled no part is fallowed in the sense of Tull. Besides the planting, the following year is repeated over the whole field indiscriminately. To make this husbandry parallel, the corn should be planted in lands, leaving every other land for fallow. What I mean by a land is the ground marked out by the plough in going the first bout & is a rod or thereabouts in width. Tull’s system, originating in England was there applied of course only to the cultivation of the small grains whose roots having but little diffusion leave the intervals, tho’ only a few feet in width, unoccupied and undrawn and therefore to the full benefit of the fallow.

I think there can be no doubt but these fallows must improve the fertility of the soil greatly. Such frequent ploughings and harrowings, the dews the rains & other deposits from the atmosphere particularly of fixed-air, aided by the shade of the growing grain must have this effect. I beleive therefore that Tull was perfectly right on his principle, and only erred in carrying it too far—in supposing that it’s efficacy would supersede the necessity, & use of manures intirely, and of itself supply the waste occasioned by, a constant procession of crops. Had he combined his principle with the principle of manuring, as has been subsequently done in England, his System would have been perfect, and left nothing for others to do, but to invent and perfect the best practical means of carrying the System into complete effect. The greatest improvements in the Agriculture of England have arisen from the adoption of his principle combined with manures. It led the way to fallow crops, instead of barren fallows; to drilled crops instead of the broad cast; to the invention of their numerous implements for effecting the most perfect pulverization of the soil; to the unwearied pains they take, to the indispensable point they make of it, to obtain this bed of tilth for all their Seeds and plants. And hence has arisen the wonderful fertility of their fields, & the wonderful crops they produce. How it is, that tillage cooperates so powerfully with nature in improving the fertility of soil it may be difficult to explain. It is probably by enabling the Atmosphere to act upon it with much greater effect than it can upon a consolidated surface. It disposes the soil to absorb, and retain a much greater quantity of the falling dews. And dews are manure. The fixed-air, precipitated from the atmosphere I should suppose must mix and combine with it in greater quantities. Fixed air contains much carbon, and carbon is manure. The internal fermentation must be greater & the putrefactions of course. The cause or causes, however, interesting as the inquiry is to curiosity, is not so important to be known so long as the effect is certain, universal, & great.

The recorded facts and experiments attestng the prodigious effects of tillage not only on the growing crop, but on the succeeding crops are too numerous for recital & I presume are too well known to you to need a referrence. But it appears to me that on this subject the Agriculturists of our Country are much in want of information & exc[i]tement. May I hope that your attention will be directed to this object. Never was a time more propitious for giving the needed information with effect. Such is the general ardor, kindled up in all parts of our Country for agricultural improvements, that agricultural information is every where sought after & devoured with avidity.

I pray you to forgive the liberty I have taken, & the trouble I have given you by this long & I fear tedious letter. And believe me to be with unfeigned esteem & attachment Yr. Obed. Servt