A is the fore Side of the Box. B the hinder Side lying down. C is the Piece H of [Fig. 10.] which makes a sort of Shelf in the Box at its left End. D at the right End makes another like Shelf, underneath which, the Fork of the Brass Spindle is turn’d by the Crank in the End of the wooden (false) Spindle. By means of these Shelves, there is room for the Two wooden false Spindles to come the further into the Carriage, without lessening the upper Part of the Box. E and F are the Two Ends of the upper Part of the Box, made by the Two Pieces G and C of [Fig. 10.] When the hinder Side B is rais’d up, and screw’d to these Ends, the Box is complete.
We put a Lid upon this Box, which is hing’d on to its right or left End. This Box (having the Brass Seed-box at its Bottom) is to be placed into the Middle of a Frame or Carriage.
[Fig. 13.] shews the Inside of the Carriage lying down. A is the hinder Side, Eighteen Inches long, Dove-tails and all, and Six Inches broad. B the fore Side of the same Length with the hinder Side, and Eleven Inches broad. This Five Inches greater Breadth than the hinder Part is, because a greater Height is required on the fore Side, on account of the Hopper’s being drawn, and the Plough held up by that and the Pieces that must be fix’d to it. C, D, are its Two Ends, Six Inches long, beside their Dove-tails, and Six Inches broad. E and F are Two Pieces each Six Inches long, whose Ends are to stand against the prick’d Lines a b and c d of the hinder Side, and their other Ends against the prick’d Lines in the fore Side, which are opposite to these. The Breadth of each of these Pieces is Four Inches: When they are in their Places, their lower Edges come even with the Bottom of the Carriage. Their Use is to support the Ends of the Spindles which come just thro’ their Holes, after each of them have passed their Hole at its respective End of the Carriage.
All this Carriage is made of Board full half-inch thick; The Ends C and D are made of double Thickness by another Piece of Board added to each, that covers all their Insides, except their Dove-tails. These Boards with which they are lin’d, are nail’d to them, with their Grain going a different Way, and crossing the Grain of the Board at the End, either at right or oblique Angles. This prevents the Holes from splitting out, and makes the Holes of a double Thickness; whereby the Spindle is the less worn by them, in case there are no Brass Wreaths to enter them.
The middle Pieces E and F are lin’d by their whole Surfaces, in the same Manner as the Insides of the Ends are lin’d.
When these Ends and middle Pieces are in their Places, a wooden Cylinder, of the exact Diameter of the Holes, is thrust thro’ all Four, to hold them exactly true, whilst the Ends and middle Pieces are all screw’d fast into their Places.
The prick’d Lines are drawn all round the Carriage, thro’ the Centres of the Holes, and at equal Distance from the Bottom of the Carriage, which is an Inch and Three quarters, and the One-eighth of an Inch. This prick’d Line is a Direction how high to nail on the Ledgers G and H, whereon the Box is to stand; and the Distance the upper Surface of the Ledger must be above the prick’d Line, is the Semidiameter of the Brass Spindle; and the Thickness of the Brass Box above the Spindle, or which is the same thing, the Distance between the Centre of the great Hole of the Brass Seed-box, and the Plane of the Top of its Mortise, being half an Inch and half a quarter, strike a Line above the prick’d Line parallel to it, at this Distance above, and then nail on the Ledger, with its upper Edge at this Line. This, with its opposite Ledger plac’d in the same manner, will support the Box with the Axis of the Spindle of the Seed-box, at equal Height with the Centres of the Holes of the Carriage; so that if those Holes are parallel to, and equidistant from the fore Side and hinder Side of the Carriage, and the Axis of the Brass Spindle be placed in the like manner parallel to, and equidistant from the fore Side and hinder Side of the Box; then when the Box is thrust down in its Place, upon these Ledgers, and the wooden (false) Spindles are placed into their Holes, their Axis will fall into a strait Line with the Axis of the Brass Spindle, as they ought.
[Fig. 14.] shews the Carriage laid open. A is its back Side lying down. B is its fore Side standing up. C is the square End of the left (false) Spindle, whereon a Wheel is to be put up to the Shoulders of the Spindle, quite close to the Ends of the Carriage. This Spindle, being an Inch and an half Diameter, is held in its Place, and kept from moving end-ways, by Two Wreaths; the one at a, bearing against the Inside of the End of the Carriage, the other Wreath at b, bearing against the left Side of the middle Piece; which Wreath keeps the Spindle from moving towards the right Hand, as the other does from moving towards the left. D is the square End of the other wooden Spindle, whereon a Wheel must be placed in the same manner as the other Wheel. This Spindle is kept from moving end-ways by Two Wreaths, in the same manner as the other Spindle is; but this right-hand Spindle, being that which turns the Brass Spindle by its Crank, which enters the Fork, should have its Wreaths of Brass, like those describ’d in [Fig. 17. Plate 4.] Part of which Wreaths entering about Three quarters of an Inch into the Hole of the End and middle Part of the Carriage, being firmly screw’d on to the Spindle, prevent the Friction that would otherwise be betwixt the Wood of the Spindle, and the Wood of the Holes; which Friction wearing the Wood of both, would in time cause the Spindle to be loose in its Holes, whereby its Axis would deviate from the strait Line it should make with the Axis of the Brass Spindle, and make an Angle with it; and then the Crank would change its Place in the Fork at every Revolution of the Wheels; and if the Hole should be worn very wide, and the Spindle worn much less, the Crank might let go the Fork; but when the Wood is of this Thickness, and each Hole has Wood in it, with its Grains pointing different ways, it would be many Years before the Holes would become large enough for this to happen, tho’ only wooden Wreaths were used; and as to the Two Wreaths of the left Spindle, they may be of Wood, because tho’ that Spindle should grow loose, it is no Damage; for it only serves to bear up that End of the Carriage; but he that has this Sort of Brass Wreaths for the hinder Hopper of a Wheat-drill, may take them thence, and place them upon these Spindles, and remove them again to the Wheat-drill when that is used; for that and the Turnep-drill are very rarely, or never, used at the same time.