The Wood behind on the upper half is cut away as the Bottom-Plate of that half is; and into the thickness of the Wood, close by the right and left-hand side of this Notch is a small square Wyer-staple driven, which we may call the Matrice-Check; for its Office is only to keep the Shanck of the Matrice from flying out of this Notch of the Mold when the Caster is at Work. And the Nuts and Screws of the Carriage and Mouth-piece, &c. that lie under the Bottom-Plate, are with small Chissels let into the upper-side of the Wood, that the Bottom-plates may lie flat on it.
Sect. XVI. Of justifying the Mold.
Although the Mold be now made; nay, very well and Workman-like made, yet is it not imagin’d to be fit to go to work withal; as well because it will doubtless Rag (as Founders call it; for which Explanation see the Table) as because the Body, Thickness, Straightness, and length of the Shanck must be finisht with such great Nicety, that without several Proofs and Tryings, it cannot be expected to be perfectly true.
Therefore before the sinking and justifying the Matrices, the Mold must first be Justified: And first, he justifies the Body, which to do, he casts about twenty Proofs or Letters, as they are called, though it matters not whether the Shancks have yet Letters on them or no. These Proofs he sets up in a Composing-stick, as is described in §. 17. ¶. 2. Plate 19. at G, with all their Nicks towards the right Hand, and then sets up so many Letters of the same Body, (which for Distinction sake we will call Patterns) that he will justifie his Body too, upon the Proofs, with all their Nicks also to the right Hand, to try if they agree in length with the same Number of Letters that he uses for his Pattern; which if they do not, for very seldom they do, but by the Workman’s fore-cast are generally somewhat too big in the Body, that there may be Substance left to Justifie the Mold, and clear it from Ragging. Therefore the Proofs may drive-out somewhat, either half a Line (which in Founders and Printers Language is half a Body) or a whole Line. (more or less.)
He also tries if the two sides of the Body are parallel, viz. That the Body be no bigger at the Head than at the Foot; and that he tries by taking half the number of his Proofs, and turning the Heads of them lays them upon the other half of his Proofs, so that if then the Heads and Feet be exactly even upon each other, and that the Heads and Feet neither drive out, nor get in, (Founders and Printers Language, for which see the Table) the two sides of the Body are parallel; but if either the Head or Foot drives out, the two sides of the Body are not parallel, and must therefore be mended.
And as he has examin’d the Sides of the Body so also he examines the thickness of the Letter, and tries if the two Sides of the thickness be also parallel, which to do, he sets up his Prooves in the Composing-stick with their Nicks upwards. Then taking half of the Prooves, he turns the Heads and lay the Heads upon the Feet of the other half of his Prooves, and if the Heads and Feet lies exactly upon each other and neither drive out or get in the two Sides of the thicknesses are parallel. But if either the Head or Foot drive-out the two Sides of the thicknesses are not parallel; and must therefore be mended.
Next, he considers whether the sides of the Body be straight, first by laying two Letters with their Nicks upwards upon one another, and holding them up in his Fingers, between his Eye and the Light, tries if he can see Light between them: For if the least Light appear between them, the Carriage is not straight. Then he lays the Nicks against one another, and holds them also against the Light, as before: Then he lays both the Nicks outward, and examines them that way, that he may find whether either or both of the Carriages are out of straight.
But we will suppose now the Body somewhat too big, and that it drives out at the Head or Foot; and that the thickness drives out at the Head or Foot and that the Sides of the Body are not straight. These are Faults enough to take the Mold asunder: but yet if there were but one of these Faults it must be taken asunder for that; by unscrewing the Male-Gage, to take the Body off the Carriage, and the Carriage off the Bottom-Plate.
Having found where the Fault of one or both sides of the Body is, he lays the Body down upon the Using File; and if the Fault be extuberant, he rubs the Extuberancy down, by pressing his Finger or Fingers hard upon the opposite side of the Body, just over the extuberant part; and so rubbing the Body hard forwards on the Using-File, and drawing it lightly backwards, he rubs till he has wrought down the extuberancy, which he examins by applying the Lyner to that side of the Body, and holding it so up between his Eye and the Light, tries whether or not the Lyner ride upon the part that was extuberant; which if it do, the extuberancy is not sufficiently rub’d off, and the former Process must again begin and be continued till the extuberancy be rub’d off. And if the Body were too big, he by this Operation works it down: Because the extuberancy of the Body rid upon the Carriage, and bore it up.
And if the fault be a Dawk, or Hollow in the Body, then he Works the rest of that side of the Body down to the bottom of the Dawk, which by applying the Lyner (as afore) he tryes, and this also lessens the Body.