Resp. If you can procure Men to dig it faithfully in Pieces, not above Two Inches and an half thick, at the Price of about Eight Shillings per Acre, it would do very well, and answer all the Ends of Tillage; but, tho’ you bargain with them to dig it at that Size for Three Pounds per Acre, you will find, upon Examination, most of the Pieces or Spits, which are dug out of your Sight, to be of twice that Thickness. And no great Quantities can be this way managed, altho’ the Price of Corn should answer such an extravagant Expence.
Farm. Since it is so difficult to bring our strong Land into Tilth, after it has rested, that it cannot be speedily done by a Plough without a Coulter, or by one with a Coulter, in wet Weather or dry, nor with a Breast-plough, without a certain Expence, and an uncertain Success, the Spade is too chargeable a Tillage for the Field: It seems to me, upon the Whole, that we are Losers by this inaratæ gratia terræ, unless we could contrive some other Method of reducing it sooner, and with less Charge, into Tilth; for I observe, that, when we sow it upon the Back, the Corn and Grass (or Couch), coming both together, exhaust the Ground so much, that by that time we can (which is about Three Years) reduce the great Lumps to a tolerable Fineness, it grows full of Grass and Weeds (which we call Foul), and loses that Fertility we expected it should acquire by Rest, becoming, in our Terms, both out of Tilth, and out of Heart.
Resp. If you know all this to be true, and that without a Coulter you cannot break it up at all; and that with one Coulter you cannot any way cut the Furrow small enough, or less than Ten Inches broad; why do not you cut it with Four Coulters, which will reduce the same Furrow into Four equal Parts, of Two Inches and an half each in Breadth, and of the Depth of the Staple, tho’ that should be Two Spit, or Sixteen Inches deep?
Farm. How can that be done?
Resp. Every jot as easily as with one Coulter: For, before the Furrow is raised by the Share, it lies fast, and makes a sufficient Resistance equally against the Edges of all the Coulters; tho’, after it be raised and loose, it yields and recedes every way, except downwards; so that it cannot be cut by any Edge, but such as attacks it perpendicularly from above, as that of the Spade does.
Farm. This seems to me reasonable; and, having very lately heard talk of this Plough, I would gladly know more of it.
Resp. The Furrow, being cut into Four Parts, has not only Four times the Superficies on the Eight Sides which it would have had on Two Sides; but it is also more divided cross-ways; viz. The Ground-wrest presses and breaks the lower (or Right-hand) Quarter; the other Three Quarters, in rising and coming over the Earth-board, must make a crooked Line about a Fourth longer than the strait one they made before moved; therefore their Thinness not being able to hold them together, they are broken into many more Pieces, for want of Tenacity to extend to a longer Line, contrary to a whole Furrow, whose great Breadth enables it to stretch and extend from a shorter to a longer Line, without breaking; and, as it is turned off, the Parts are drawn together again by the Spring of the Turf or Swerd[258], and so remain whole after Plowing. Thus the Four-coultered Plow can divide the Soil into above Twenty times more Parts than the common Plough; and sometimes, when the Earth is of a right Temper betwixt wet and dry, the Earth-board, in turning the Furrows off, will break them into Dust, having more Superficies than is made by Four common Plowings; and it is impossible there should be any large Pieces amongst it.
[258]A swerdy Furrow cut off by only one Coulter, being whole, is apt to stand up on its Edge, or lie hollow; and then, being open to the Air, it does not rot; but when it is cut by several Coulters, it has not Strength to support itself, it falls down, lies close to the Earth under it, and, excluding the free Air from the Turf, it soon becomes rotten. And for killing the Turf of swerdy Land is the chief Use of the Four-coultered Plough: For doing of which there is this Advantage, that as in a whole Furrow there are often Strings of Couch-grass, Three or Four Feet long; but, when cut by this Plough, there is scarce a String left of one Foot long: And these Strings being apt to send out Roots from every Knot or Joint, the shorter they are cut, the more they will be exposed to the Air and Sun, which will kill them the sooner.
Now, what a prodigious Advantage must the Influences of the Atmosphere have upon these small Parts, for making a further Division of them! Frost, Water, Drought, and nitrous Air, easily penetrate to their very Centers, which cannot in the largest of them be more than one Inch and a Quarter distant from their Superficies. This Advantage, with a few subsequent common Plowings, performed in proper Seasons, resolves the Earth almost all to a Powder. The Swerd, some being immersed or buried and mixed among so great a Proportion of Mould, is soon rotten and lost; some of the Swerd lying loose a-top, the Earth presently drops out of it; and then the Roots are dried up, and die. Thus is the whole Staple of the Ground brought into perfect Tilth in a very short time beyond what the Spade ever does in such swerdy Land.
Farm. What sort of Weather is best for using this Plough?