Fleta minor the laws of art and nature, in knowing, judging, assaying, fining, refining and inlarging the bodies of confin'd metals : in two parts : the first contains assays of Lazarus Erckern, chief prover, or assay-master general of the empire of Germany, in V. books, orinally written by him in the Teutonick language and now translated into English ; the second contains essays on metallick words, as a dictionary to many pleasing discourses, by Sir John Pettus ... ; illustrated with 44 sculptures.

CHAP. XXXV. Of Filing or Joyning the proof Ballance or Scales.

[Section. 1] FILING and Joyning of proof Scales is a special Science, and is the true Master∣piece, which is not known to every one that can make them, and is done thus; when the proof Ballance is Filed out, (as hath been said before) then make, of Sil∣ver, two flat clean and smooth scales, and also two very [Section. 2] thin small scales, the which are called inset scales, which altogether are to be as heavy as the Ballance, or rather a little heavier than lighter, and put fine silk Thred to them, in length of the whole Ballance, from one end to the other, such Threads are to have a neat Knot on the top, [Section. 3] whereby the strings may hang to the ends of the Bal∣lance, and when the strings are made fast to the scales, then weigh them one against the other, with another proof scales, and see if they do weigh alike, then hang them to the ends of the Ballance, put the inset scales therein, and hang the Assay-ballance in a Case made on purpose, and draw them up gently, if then the scales do turn on the one side; that is, when you do press the scales down on the one side, that the scales remain down, as also on the other side, and will not go back but remain standing, then the fault is in the Beam, that on the same places is fitted [Section. 4] too high, from which the Ballance falleth on both sides, and will not stand just; if you know this, then make the Beam on both sides somewhat lower, but so that it be not higher on one side than on the other; to the rectifying of this, you should have a little smooth plate of Pear∣tree,

upon which make a Cross stroak, and in the midst of the Cross must be a little Hole, and upon this lay the fi∣led Beam of the Ballance, so that the little Wartz in the little Holes, and the Beam and little Tongue may come to lye upon the stroak, then you may soon see how the Beam, the little Tongue, and the Ends are fitted, that so you may help and fit it.

So when the little Beam is thus prepared, that it may stand near the Ends, a little lower than the Line upon the little plate, then lay it in the Fork, in its place; give it the right quickness so that it draw well and distinctly the smallest of the Weights of the Proof-Weights (and not stop in its lodge) nor have too much room (that is to say) that the holes below of the Fork may not stand too far off from the little Wartz, but only that one may see through to try it.

[Section. 5] Now, when the Proof-Scales are thus made with the greatest dilligence, see that it has its quickness, and does not stand; also that there be no fault neither in the Beam or little Wartz, it must stand right both with the scales and also without them, if it doth not this, but goes heavy on the one side and light on the other, there is the greatest fault, which to mend many do not understand; but thus is it to be done, help the Ballance above on the one end, and on the other side on the scale, (that is thus) bend the one end a little down, or a little narrower, then doth it give presently the Ballance on the other side, weight, for the length, and takes so much from the other side of the scale, that the Ballance may stand in again in the Fork, then try it again whether it do well either with a Burthen or without a burthen, and that it may have its right quickness; but if it does not so, but goes still a little at one side, then have you done too much, then help it with bowing back of the end, and the scale; but if you have not bowed the end on the right side, then the Bal∣lance

will go more false, therefore you may easily see on which side it is to be helped with binding and fitting them, and you may also use this dilligence, that when you have bent the end on the one side, and that you also do the like on the other side of the scale, but make it even with Weights, that the Ballance may stand right in the Fork, by which you may see how it doth stand in ei∣ther with Weight, or without, and then it is easily to be corrected.

It requires great Pains to fit a Ballance thus, for it doth try many times a Master; yea, it maketh him so err, that he cannot know oft times how further to pro∣ceed: yet this way which I have here proposed is the best to such a fittingness: and it must certainly be mana∣ged by an ingenuous, and not a dull Soul. Thus much I thought good to signify, for the clearer Instruction, be∣cause 'tis very pertinent to our present Discourse of Pro∣ving, therefore I omitted it not.

[Section. 6] And that the Proof-Ballance may be preserved clean and pure from Dust, and also that in time of use the wind may be no hindrance, but stand firm, therefore it is to be put in a clean and well formed Proof-Case made of wood, which on both sides is to be set with bright and clear Glass, that the Light may come into it, and that all things may well be seen (the Form is shewn in the following Sculpture: And, for conveniency of the Sight, it were best to colour the Inside of this Case green, because the Fire is hurtful to the Eyes, and by this colour they are again quickned and refreshed.

[illustration]

Sculpture. XII.

Deciphered.

1. The Out-side of the Case for the Ballance.

2. The In-side of that Case wherein the whole Ballance is to hang, and be kept from Dust.

Notes

• To fit Scales.
• The weight of the Scales to the Bal∣lance.
• The Knots,
• When the ballance fal∣leth.
• To make the Ballance, to stand true.
• The Case for the Proof Ballance.
• Or, oyld Pa∣per.