Sect. 21. How to border your plate, that it may contain your Aqua fortis.

GEt soft wax, either red or green; if it be in Winter, soften it at the fire; in Summer it wil be sufficiently soft of it self: In the managing of it, put it round the brims of your plate, raised about half a quarter of an inch from the surface of the plate, being as it were a little rampart; in such sort, as Page  33 that placing your plate very levell, and afterwards pouring your Aqua fortis upon it, the water may be retain'd by the means of this border of wax, so as, that the water may be equally diffused all o∣ver; but before you pour it on (to prevent its so∣king through between the wax and the plate) if need require, heat a little piece of Iron, and run it over on the out side where the plate closeth with the border.

Having thus bordered your plate, take common Aqua fortis, such as is used by the Refiners, pure and good, and mingle it with common water, be∣ing in quantity about the third part of your Aqua fortis; or if you have Aqua fortis, of which you have made former use in etching, mingle it with the pure Aqua fortis in stead of common water, and let the quantity be proportionable to the strength of it; then pour it gently upon the plate, in such sort as that it may remain upon it the thicknesse of half a fingers breadth all over: if you make use of the strongest Aqua fortis, be carefull to mingle it with the greater quantity of common water.

Then you shall see that the water will work and bubble up in those stronger hatchings that are most firmly stricken; as for those that are fainter you shall perceive them clear at first, and of the colour of the copper, the water not making on a sudden any other operation than appears to view.

Afterwards, when you shall have perceived the water to operate a small time, pour it off from the plate into some vessell which is most proper to con∣tain it, as into an earthen dish well varnisht, or the like, then throw some fair water upon the plete, to Page  34 extinguish and wash away the remainder of the Aqua fortis, which was upon the plate, then dry it by the fire, as you have been taught before, when we dis∣courst of hard varnish; and as touching your soft varnish and Aqua fortis of the Refiners, be carefull in especiall manner to cause to evaporate that moisture, which in the Winter time is commonly between the copper and the varnish, before you lay on your Aqua fortis: The superfluous moisture being evaporated from it, take your mixture of oyl and grease, as is before mentioned in the be∣ginning of this discourse of hard varnish, and therewith cover those places which ought to be most tender and sweet; and having covered them the first time, lay on again upon your plate the same Aqua fortis which you had taken away, and leave it on for one half quarter of an hour, or a longer time, according to your discretion; then take off the Aqua fortis, and cover with your mixture those next places, as you shall see occasion: And as you would have your lines or strokes to be deeper and deeper, so cover the sweeter part by degrees with your mixture, that the Aqua fortis may ly the longer on the deeper strokes.

Lastly, lay on yet again the aforesaid Aqua for∣tis, and leave it on for the space of half an hour, either more or lesse according to the strength of the water and nature of the work, then take it away and cast some fair water upon the plate again.

That being done, take off your border of wax, then heat your plate, so that the oyly mixture and the varnish may throughly melt; then wipe it well with a linnen cloth, afterwards rub it all over with Page  35 oyl-Olive, with a piece of old beaver roll'd up, and that being done, touch it over again with your graver in those places where it shall be needfull.

One thing I shall advertise you of, which is, that while the Aqua fortis is upon your plate, you take a feather and dip it to the bottome of the said A∣qua fortis, sweeping it along to remove the froth or scum which gathers upon your strokes or hatchings, while the water makes its operation; as also to give the more way to the operation of the water, and to see if the varnish be not broke up, which the bubling of the water hinders you from dis∣cerning.

You may also take notice that the Aqua fortis of the hard varnish, will serve excellently well to eat into the work made by the aforesaid soft varnish, and that the manner of applying the oyly mixture, is all one with that of hard varnish, and who ever useth it may be assur'd, that it is much more excel∣lent for this purpose than that of the Refiners; Moreover, it is not so subject to cause the varnish to break up, nor to many other accidents, as the being hurtfull to the sight, or to ones health, as that of the Refiners is, neverthelesse every one may use which of them he pleaseth.