Dictionarium polygraphicum. Yellows.

Dictionarium Polygraphicum:
Or, The Whole Body of Arts Regularly Digested.
Vol II.
London: Printed for C. Hitch and C. Davis in Pater-noster Row, and S. Austen in St. Paul's Church Yard. MDCCXXXV.
There are some objects, which have the appearance of gold, shining through the colours of green, red, or blue; such as some sort of flies and beetles, and the Cantharides.

This golden transparency is very well imitated by laying on, the drawing some leaf-gold on the shaded part, a little giving into the light side of the print.

The way of laying on the leaf-gold, is to wash the paper, where the gold is to be, with strong gum-water, and when it is grown something dryish, to lay on the gold as smooth and even as possible, pressing it down close with cotton. But in doing this, care must be taken, that in laying on the gum-water, you do not exceed the limits you would have the gold appear to shine.

In this case the gold is to shine only through the transparent colour, which is to be laid upon it.

You must observe this, that the leaf-gold will not regularly receive water-colours, and for that reason it must be stroak'd over with a little thin liquor of ox-gall in a painting-brush of camel's hair, and then it will receive any colour that we have a mind to paint upon it, and will hold it. So you may have golden reds, golden greens, and golden blues, golden yellows, golden purples, and whit you please.

The green may be first the verdigrease green, orthefap-green; the reds may be lake or carmine; the purples, lake and fine indigo, or carmine and indigo; and for the blues, indigo on the dark side, and on the light side a little stroke of ultramarine blue, suit to shine into the light, and it will have an admirable effect.

NB. There is to be found upon rose-trees in June and July, a kind of beetle of a golden green colour, which will serve for a direction in this kind of painting.

But if gold itself be us'd, it will be belt to polish it, which you may do afeer the following manner:

There are to be seen in many manuscripts fine golden letters, which rise above the surface of the vellum or paper, the composition that raises them above the paper, is said to be made of vermilion and the white of an egg, whisk'd or beaten up to that consistence, as is call'd an oil, work'd together like a kind of paste, and with a stamp fix'd to the vellum or paper, with gum Arabick; on this figure of a letter wash some strong gum-water with a camel's hair pencil, taking care that the gum does not reach more than the out-lines; then lay on the leaf-gold close with some cotton, and as soon as it is dry, rub it with some dry cotton, and then polish it with a dog's tooth; this will make it appear, as if it was really cast in gold.

There is besides this another way of working in gold, and that is perform'd by shell-gold; but then it must be pure gold, and not that which is brought from Germany, which will turn green in a few day's time.

Before you use this gold, cover the shady parts with vermilion; and after your gold has been well rectified with spirits of wine, lay it on with gum-water, which will readily mix with it, and when it is dry, polish it with a dog's tooth.

In laying on the gold it may be best to leave the lights vacant of it, and so it will make a much brighter appearance than if the object was covered all over.

But if one was to cover by accident the whole piece with gold, there is no better way to set it off, than by tracing over the shady parts with gall-stone; or, which is much preferable, the yellow, the composition of which you will find below, made of French berries, 1 mean that which is the deepest in colour; a little minium brightens it very much. How the minium is to be rectified you may see among the reds, and polish the go!d before you use the minium on it.

After gold I shall treat of yellows, as they fall gradually in their course of strength.

The first yellow is a kind of straw-colour, and is made of flower of brimstone, which of itself is fine enough to mix with gumwater.

A common way of illuminating prints, is by giving the tincture of gamboge for a yellow, and this may be of two or three sorts, either fainter or stronger; the last to be a shade to the first, and the last to be shaded with the preparation of French-berries.

The great Mr. Boyle, in some papers he left behind him, say, that if the roots of barberries are cut, and put into a lixivium made strong with water and pearl-ashes, there will be a fine yellow colour produe'd from it; which having been try 'd, succeeds very well.

He likewise proposes another way for making a transparent yellow, which is, by washing the root of mulberry-tree very clean from the earth, in common water, and boiling it in a strong lixivium of pearl-ashes and water; and it will afford a yellowish juice, from which may be extracted a tincture, much deeper than the former.

Yellow oker will make another good pale yellow; but it is a colour, rather of too much body for illuminating of print; but yet being well ground with gum-water, it is or use after it has been well wash'd.

The plant celandine will afford another good yellow, by infusing inn water, and pressing it gently, and then boiling the liquor with a little alum; this yellow will incline a little to green.

But a yellow, which some prefer to the rest, and may be us'd in several capacities of lights, is one made of French berries, prepar'd as follows:

Boil two ounces of French berries in a quart of lixivium made of pearl-ashes and water, 'till the liquor will give a fine tinge of yellow to a bit of paper dipp'd into it, then pour it off from the berries, let the liquor cool, and then put it into bottle for use.

Then again put a pint of the same lixivium to the berries, and boil them 'till the liquor is as deep-coloured as gall-stone; and this will be fit for the shade of any sort of yellows you can use.

This may be boil'd 'till it produces a brown colour; and will, with a little ox-gall, serve to shade any leaf-gold, that has been laid on paper, and is much preferable to gall-stone in imitating any gold colour. It answers well upon a tincture of gamboge, or any of the former yellows.

Next to this may be reckon'd the tincture of saffron, in common water only, which affords a bright reddish yellow, such as one would have (to cover the shadowed parts or a print) for an orange-colour; and when saffron is infus'd in rectified spirits of wine, there is nothing higher; but then, except the colour be loaded with gum Arabick, it will fly.

As for a deep yellow with a body, Dutch pink comes the nearest of any to the before-mention'd strong yellow made of French berries in point of colour; and of a lighter yellow is the English pink, which is still made of French berries, and in a body likewise.

Also a good yellow colour, for illuminating of prints, may be extracted from the French roots of ginger, and it makes a fine green with transparent verdigrease.

N B. The English and Dutch yellow pinks are made with French berries ground to a fine powder, and boiled.

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