Part 30

But as for the Brass Spindle of the Turnep-drill, we can have but one Set of Notches in it[267]: And therefore, tho’ we can increase the Proportion of Seed by enlarging the Notches, or perhaps by doubling their Number; yet we cannot lessen the Proportion of Seed by the Notches, unless we have a new Set of them, and that will occasion a Necessity of having another Spindle; but, as to the Setting-screw of the Turnep-drill, it will increase the Proportion of Seed with the same Notches, much more than the Setting-screw of the Wheat-drill will do.

[267] But by putting on a Wreath (that is a little broader than the Mortise) upon the Spindle (made longer for that Purpose) we can, by changing this Wreath from one End of the Spindle to the other, have Two sets of Notches of different Sizes, and of different Numbers in it: Or if we would have Three Sets, we need only make Use of Two such Wreaths, and let the Spindle be long enough to receive them. So we may use which Set we please.

Tho’ several Sets of Notches may be useful to those who drill many Sorts of fine Seeds different in Magnitude in a very great Degree; yet I never found more than one Set of Notches necessary in this Spindle.

Nor have I used any more than one Set of Notches in one Mortise of any Sort; but in a wide Mortise, there may be made a double Set of Notches, consisting of Two Rows, all of equal Bigness, and half of the Length, and double the Number of a single Row, one End of each Notch reaching to the Middle of the Mortise, and pointing against the End of an Interstice, that is between Two or its opposite Notches.

If ever there shall be Occasion for this Sort of Notches, it must be when a great Proportion of Seed is to be drill’d by a small Spindle, and low Wheels: The Smalness of the Spindle may not, by a single Set, admit of a sufficient Number of Notches (of a proper Bigness) in its Circumference; not that a double Set, by its double Number, will throw down a greater Quantity of Seed than a single Set of the same Width and Depth, but a less Quantity; But it may be feared, that a very small Number of Notches might not spread the Seed so much as to cause it to lie even in the Chanels, one Notchful falling all to the Ground, before any of the next Notchful reaches it, which would make Chasms or Gaps in the Row of Corn or Legumes: This, such a double Number of Notches will certainly prevent.

It would seem, that the higher the Wheels, the more need there should be for this double Set of Notches: But it appears to be otherwise; for the greater Distance the Seed has to fall, the more it spreads, and strikes oftener against the Funnel and Trunk; and by that means a Notch from high Wheels will, with the same Quantity of Seed, supply a greater Length of the Chanel (or Furrow) than a Notch will from low Wheels.

In all my Practice I never had any Occasion for such a double Set of Notches, either with high or low Wheels, or even when I drilled into open Chanels, without Funnels or Trunks to my Drill-plough; and yet my Rows of St. Foin, and of Corn, were always free from Gaps, being equally supply’d with Seed from one End to the other.

If ever there is Occasion for more than a single Set, it must be for Beans, for which also I think a large Spindle is better than a double Set of Notches in a small one. The largest Spindle I have known made, is of Two Inches and an half Diameter, and that only for Horse-Beans.

The best Sort of Notches for a double Set are those which have convex Bottoms; because such are less liable to drop their Seeds without the turning of the Wheels, than any other Sort: And a double Set must be in greater Danger of this, as the Tongue is always hindered from pressing so closely against any Notch, being held open by the Seeds on the opposite Interstice; which is contrary to a single Set, where no Seed can lodge at either End of a Notch, to hold open the Tongue, or hinder its pressing against it.

_Note_, When I made my Boxes of Wood, I had double Boxes, with a Partition between such a double Set of Notches; but never made such in Brass, not knowing whether that Partition, by its Thinness of hard Metal, might not cut the Spindle: Yet I never found any Occasion for a double Row of Notches. I made those double Boxes only for drilling Two Sorts of Seeds at once into the same Chanel.

The other Way of varying the Proportion of Seed in the same Boxes, is by the Diameter of the Wheels, when we can alter them; for Wheels, of what Diameter soever they are, must turn round all the Notches at one Revolution; so that Wheels of Twenty Inches Diameter will deliver out a third Part more Seed than Wheels of Thirty Inches Diameter, into the same Length of the Chanels; but we seldom have any Occasion to alter the Wheels, unless it be on account of planting a Species of Seed of a different Magnitude, as the largest Sort of Peas, and small-grain’d Wheat, or St. Foin Seed are.

These are all the Ways we have to alter the Proportion of Seed, we drill with the same Seed-boxes; these Two Sizes, already described, being sufficient for all Sorts of Corn and Seeds which we commonly sow, from Marrow-peas to Turnep-seed; but, for drilling of Beans, the Boxes must be larger, and are commonly made of Wood, the Spindle Two Inches Diameter, or more, and the Boxes Two Inches wide: Where note, That this Increasing of the Width of the Mortise, from an Inch and an half, to Two Inches, increases the Quantity of Seed to almost double; because this Half Inch is all added to the Middle of the Notches, where they are deeper than their Ends; the Bevel of which takes up a considerable Part of the Length of the Notches. For Beans, they also contrive to have their Wheels as low as conveniently they can. These Wooden Drills are now become common in many Places.

The Wooden and Brass Seed-boxes differ not in any of the most essential Parts of them; only the Wooden Box must be thicker, as the Wood is not so strong as Brass; the Spring is made strait instead of crooked; and, being let into the Back of the Wooden Tongue, bears against it at each End; and the Chanel, into which it is placed, being made hollow in the Middle, the Spring has its Play there, and must be stiffer and have a little more Play in the Bean-drill, than in any lesser Seed-box.

I, at first, made all my Seed-boxes of dry Box-tree Wood, which performed very well, and are still used: But, a few Years ago, a Gentleman advised me to make them in Brass; the doing of which has put me to a great deal of Trouble and Expence, for want of understanding the Founder’s Art: Yet this I do not repent, because they are, in some respect, better than those made in Wood; especially to those who do not well understand their Fabric; for, to such, the Swelling and Shrinking of the Wood was inconvenient in small Boxes: And I now am told, that they are cast in _London_ of the best Brass, at the Price of One Shilling _per_ Pound, and so smooth as to require very little filing. And these Brass Boxes being also more lasting than Wood, and not much more expensive, when Workmen know how to make them, I think it not worth while to give any particular Directions for making them in Wood.

As to the Spindles of the Turnep-boxes, I have often made them with a mix’d Metal, of half Pewter, and half Spelter, which perform very well, and are easily made; because this Metal will melt, almost as soon as Lead, in a Fire-shovel, to be cast in a Mould; but Brass will not melt without a Crucible.

The first Idea that I form’d of this Machine, was thus: I imagin’d the Mortise, or Groove, brought from the Sound-board of an Organ, together with the Tongue and Spring, all of them much alter’d; the Mortise having an Hole therein, and put on upon one of the Iron Gudgeons of the Wheelbarrow; which Gudgeon being enlarg’d to an Inch and an half Diameter, having on it the Notches of the Cylinder of a Cyder-mill, on that Part of it which should be within the Mortise, and this Mortise made in the Ear of the Wheelbarrow (thro’ which the Gudgeon usually passes), made broad enough for the Purpose; this I hoped, for any thing I saw to the contrary, might perform this Work of Drilling; and herein I was not deceived.

As for placing a Box over this Mortise to carry a sufficient Quantity of Seed, it was a thing so obvious, that it occasion’d very little Thought; and an Instrument for making the Chanels, not much more; neither for applying Two Wheels, one at each End of the Axis, instead of the single Wheel in the Middle of the Axis of the Wheelbarrow.

At first my Plough made open Chanels, and was very rude, being composed of Four rough Pieces of Planks, of little Value, held together by Three Shoots, or Pieces of Wood, which held them at a Foot Distance one from the other; These Pieces, being cut sharp at Bottom, made the Chanels tolerably well in fine Ground. But I soon contrived a Plough with Four Iron Shares, to make Chanels in any Ground: This drew a Hopper after it, having Four Seed-boxes at its Bottom, carried on a Spindle by Two low Wheels, which had Liberty to rise and sink by the Clods that they pass’d over: The Seed-boxes delivered their Seed immediately into the open Chanels.

This Plough and Hopper were drawn by an Horse, and the Seed, lying open in the Chanels, was covered sometimes by a very light Harrow, and sometimes by an Hurdle stuck with Bushes underneath it.

I soon improv’d this Plough to perform better, and to make Six Chanels at once, and sometimes a great many more.

This Plough and Hopper, with their Improvements and Alterations, are shewn in _Plates_ 4. and 5.

CHAP. XXI.

Of the _Wheat-Drill_.

_Fig._ 1. in _Plate_ 4. is the Drill-plough, which makes the Chanels for a treble Row of Wheat, at Seven-inch Partitions, and covers the Seed by the Harrow which moves on its Beams. A, is the Plank, Three Feet and an half long, Eight Inches and an half broad, one Inch and a quarter thick; its upper and under Surfaces are true Planes. B, B, the Two Beams, each Two Feet Four Inches long, Two Inches Three quarters broad, and Two Inches and a quarter deep, standing under the Plank at right Angles with it, and held up to it by the Four Screws and Nuts _a_₂ _a_₂ _a_₂ _a_₂ the one being at the same Distance from the right, as the other is from the left End of the Plank.

This Plough makes its Chanels by Three Sheats, and their Shares and Trunks; the First or Foremost of which Sheats stands under the Middle of the Plank, with Part of it appearing at _b_; and is fully describ’d in _Fig._ 2, where A is the Tenon, of a convenient Size, Two Inches broad between Shoulder and Shoulder, Three quarters of an Inch thick: It is driven into the Plank thro’ a Mortise, and pinn’d up by its Hole: It stands thus obliquely, and pointing forwards, that it may stand the more out of the Way of the Funnel. The Shoulder at _a_ is a quarter of an Inch. The hinder Shoulder, from the Tenon to the Angle at _b_, is Three quarters of an Inch. The Depth of the Back of the Sheat, and Thickness of the Share, when it is on, from _b_ to _c_, is Nine Inches and a quarter; and the Angle at _c_ must be a right Angle, contrary to the Opinion of some, who fansy it ought to be acute, supposing that when this Angle is right, whilst the Seed is descending by the Back of the Sheat, the Plough, as it moves forwards, would get before the Seed, and so it might fall to the Ground behind the Trunk; but this Mistake is for want of considering the vast Disproportion between the Celerity of the Seed’s descending near the Earth, and the slow Progress of the Plough; the Seed descending at the Rate of Sixteen Feet in a Second of Time, and the Plough proceeding but about Three Miles an Hour, does not advance the Thickness of a Seed, whilst it is falling to the Ground by the whole Depth of the Sheat.

The Thickness of the Sheat is an Inch, at its upper Part. The rest of it is to be no thicker than the Breadth of the Share.

_Fig._ 3. is the Share, lying Bottom upwards. _a_ is its Point. _b_ the Socket, Three Inches long, Seven Sixteenths of an Inch broad. _c_ is the Hole, by which it is fastened up to the Sheat. _d_ is another Hole, which is never made use of, except when the Share, being fasten’d up by the other Hole, inclines to either Side; then we draw it right by a Nail driven into this Hole. _e_, _e_, are Two very small Notches, into which the Sides of the Trunk are jointed, to protect them from being torn out by the Earth or Stones that might rub against them, _f_ is the Tail of the Share, which, when it is in its Place, will make the right Angle before described in _Fig._ 2. and from which Tail, to the Fore-part of the Socket, is the Length of the Bottom of the Sheat, _viz._ Six Inches and an half. The Breadth of the Share Three quarters of an Inch.

_Fig._ 4. shews one Side of the Share. The prick’d Line _a e_ shews the Bevel of the Fore-end of the Socket, the upper Edge of which must bear upon the Fore-part of the Sheat below _f_ in _Fig._ 2. and the other Part of the Share will bear against the Bottom of the Sheat, from _d_ to _c_, and will be fastened up by a flat Nail, passing thro’ the foremost Hole of the Share, and entering the Hole _g_ in the Sheat; which Nail being bended in the said Hole (which Hole should be at least an Inch Diameter) will hold the Share fast to the Sheat; and, by unbending this Nail, the Share may be easily taken off, upon Occasion, without damaging the Sheat. _Note_, This Hole in the Share ought to be wider below than above, and the Head of the Nail of the same Shape; or else, as the Share wears thinner, it might come off. The prick’d Line, near the Fore-part of the Sheat, shews where a Shoulder must be cut on each Side of it, because otherwise the Sheat, being thicker than the Breadth of the Socket of the Share, could not enter it: But take care, that the Share do not bear against these Shoulders.

_Fig._ 5. is one Side of the Trunk, being a thin Plate of Iron, and is often made of the Blade of an old Scythe: It is to be riveted on to one Side of the Sheat, to another of the same on the opposite Side, by Three Rivets passing thro’ them both, with the Sheat in the Middle of them; which Holes appear both in the Plate and in the Sheat. These thus riveted on do form the Trunk at the Back of the Sheat. The whole Breadth of this Plate is an Inch and Three quarters; but Three-eighths of an Inch being riveted on to the Sheat, there remains but an Inch and Three-eighths for the Trunk. The Length of the Plate is the same with the Depth of the Sheat and Share, except that it should not reach to the Bottom of the Share, by about the Thickness of a Barley-corn, to the end that it may not bear against the Ground, as the Share doth. The Notch at the Bottom of the Plate is that which answers the Notch in the Tail of the Share: The Corner of the Plate at _a_ we make a little roundish, that it may not wear against the Ground.

This Plate thus riveted on the Sheat, and another of the same Form on the other Side opposite to it, compose the Trunk, which is _Fig._ 6. _a d_ is the Edge _a b_ of the Plate _Fig._ 5. _b c_ is the like Edge of the opposite Side of the Trunk. A is the Back of the Sheat, which, together with the Tail of the Share when in its Place, makes the Fore-part or Length of the Trunk. The Thickness of this Back of the Sheat is the Width of the Trunk; and from this Back of the Sheat to the said Edges of the Plates, may be call’d the Depth of the Trunk. The upper Ends of these Two Plates _a_ and _b_ we spread open a quarter of an Inch wider, for half an Inch down, than the rest of the Trunk, for the more free Reception of the Seed from the Hole of the Funnel: We likewise take care, that the Two lower hinder Concerns of the Trunk do not incline to one another, to make the Trunk narrower than the Back of the Sheat, lest the Earth should be held in by them, and fill the Bottom of the Trunk.

_Fig._ 7. is one of the hinder Sheats, and appears, in part, at _c_ in _Fig._ 1. It is fastened into one of the Beams by its Tenon, which, being driven into a Mortise, is pinn’d in by a Pin passing thro’ the Beam, and the Tenon cut off even with the upper Surface of the Beam: This Tenon stands more oblique than that of the fore Sheat, that there may be the more Wood between its Mortise and the Funnel, its hinder Shoulder being short: Its fore Shoulder at _a_ must be very short, not above the Eighth of an Inch; but its Shoulder _b_ Three quarters of an Inch. The Tenon is also shoulder’d on each Side, as well as before and behind. The Thickness of this Sheat should be greater than that of the Fore-sheat, because it is much narrower. The Depth of this Sheat, is less than the Fore-sheat, by the Depth of the Beam: It is, in all other respects, the same with the Fore-sheat, except that it and its Share are shorter. The Socket of this Share is but an Inch and One-eighth long, its Breadth half an Inch, and from the Fore-part of the Bottom of the Socket to the End of its Tail, but three Inches. Its Point from the Socket at Bottom is but Three quarters of an Inch, whereas the Point of the Fore-share is an Inch and Three quarters: There is but one Hole whereby the Share is fastened up to the Sheat. Its Trunk is no wider than the other; for we cut a Rabbet on each Side of the Sheat, that the Plates, which are the Sides of the Trunk, may come within Three quarters of an Inch of one another. Its Tenon, being narrower than the Tenon of the Fore-sheat, must be thicker than it.

The other Hinder-sheat, and all its Accoutrements, must be the same as this of _Fig._ 7.

The Workman must take care, that the Tenons of the Sheats be not made cross the Grain of the Wood; and therefore must make them of crooked Timber.

_Fig._ 8. shews how the Share is made of Four Pieces; of which _a_ is a Piece of Steel for the Point, its larger End being cut bevel for the Shape of the Fore-end of the Socket. _b_ is a Piece of Iron for the other End of the Share, from the Socket to the Tail: The other Two Pieces _c_ and _d_ are the Iron Sides, which, being welded on to the other Two Pieces, and cut off to the Length, form the Share, with its Socket, more exact than it can be made out of one Piece of Iron.

Now we return to the first Figure; where the Fore-sheat being fix’d up at equal Distance from each End of the Plank, and as near to the hinder Edges of it as can be, allowing room for the Funnel C to stand with the Fore-side of its Hole, to make one Surface with the Back of the Sheat, and for the hinder Part of the Trunk not to reach the Edge of the Plank, there must be also room for the Fore-standard D to stand perpendicular to the Plank, across the Tenon of the Sheat.

This Standard being close to the Fore-side of the fore Hopper, there must be so much room between it and the Hole of the Funnel, that the Seed may drop from the Seed-box into the Middle of this Hole. Thus much for placing the Fore-sheat.

Next, for the Two hinder Sheats; they must be placed at equal Distance from the Sides of the Beams, and so near to the hinder Ends of the Beams, that there may be room to make the Funnels in them, and their Tenons to come up between their respective Funnels E and F, and their respective Standards G and H, which Standards must be set perpendicular to the Beams.

The Distance of these Sheats from the Plank must be such, that the Wheels of the hinder Hopper may not strike against the Plank, nor against the Spindle of the fore Hopper; and the Semidiameters of these Wheels being Eleven Inches, there ought to be a Foot between the Centre of each Wheel and the Plank; but we sometimes cut Notches in the Plank, to prevent the Circle of the Wheels from coming too near the Plank.

For the nearer the hinder Sheats stand to the Plank, the better; but these Beams may be placed nearer to, or farther from the Plank, by their Screws and Nuts, at Pleasure.

These Beams must be set at such a Distance from one another, that the Shares may be Fifteen Inches asunder from the Inside of one to the Outside of the other.

To try whether all these Sheats and Shares are truly placed, set the Plough upon a level Surface; and then, if they be right, the Fore-share will touch the Surface by its Point and Tail, and likewise the hinder Sheats will do the same; except that some Workmen will have it, that the Plough goes better, when the Tails of the hinder Sheats are a Barley-corn’s Thickness higher than their Points; and then their Tails will want so much of touching the Surface.

The Shares must be all of them parallel to the Beams, and consequently to one another.

The Chanel made by the fore Share and Sheat for the middle Row, being at equal Distance between the Two hinder Sheats, is cover’d by them, they raising the Mould over the Seed from each Side of this Chanel.

The Harrow I is drawn by the Beams, to which it is fastened to their Insides at _d_ and _e_, having each a small Iron Pin, passing thro’ each End of the Legs of the Harrow, and thro’ the Beams; each having a Nut on the Outsides of the Beams, and being square in the Beams, that they may not turn therein to loosen their Nuts; but are round near their Heads, that the Harrow may easily move thereon.

The round Ends of the Legs of the Harrow are put thro’ its Head I, at the round Holes _f_ and _g_; and pinned in behind it, to the end that either Tine of the Harrow may descend at the same time that the other rises, where the Ground is uneven.

The Two wooden Tines K and L are pinned in above the Head, and have each of them a Shoulder underneath. They stand sloping; so that if they take hold of any Clods, they do not drive them before them, but rise over them. They are of a convenient Length, to give room for the Harrow to sink and rise, without raising up the Shares; and to give them the more room to move: The Legs of the Harrow are crook’d downwards in the Middle.

The Distance of these Tines from each other is Twenty-two Inches; so that each Tine going Three Inches and an half on the Outside of each Chanel that is next it, fills it up with Earth upon the Seed, from the Outsides of it; which causes the Rows to come up something nearer the inner Sides of the Chanels, than to the outer Sides, from whence the Earth is brought into them by the Tines; and the Two outer Rows by this means come up at Fourteen Inches asunder, tho’ the Chanels were Fifteen Inches asunder.

This way of covering adds more Mould to the Top of a Ridge; whereas, if the Chanels were covered by Tines going within or between them, the Mould would be thrown down from the Top of the Ridge: And these Tines stand with their Edges and Points inclining outwards, by which means they bring in the more Earth to the Chanels.

If we find, that the Harrow is too light, we tie a Stone upon it, to make it heavier; and sometimes we fix a small Box of Board on the Middle of it, to hold Clods of Earth for that Purpose.