第67章

"Take of oil of lavender, 120 grains, of copal in powder, 17 grains, red sulphuret of mercury, 60grains. The oil of lavender being dissipated with a gentle heat, a colour will be left on the paper surrounded with the copal; a substance insoluble in water, spirits, acids, or alkaline solutions.

"This composition possesses a permanent colour, and a MSS. written with it, may be exposed to the process commonly used for restoring the colour of printed books, without injury to the writing. In this manner interpolations with common ink may be removed."* * * * * * * *

Boil parchment slips or cuttings of glove leather, in water till it forms a size, which, when cool, becomes of the consistence of jelly, then, having blackened an earthern plate, by holding it over the flame of a candle, mix up with a camel hair pencil, the fine lamp-black thus obtained, with some of the above size, while the plate is still warm. This black requires no grinding, and produces an ink of the same colour, which works as fregy with the pencil, and is as perfectly transparent as the best Indian ink."* * * * * * * *

"Instead of water use brandy, with the same ingredients which enter into the composition of any ink, and it will never freeze."* * * * * * * *

"Bacteria in Ink--According to experiments which have recently been completed at Berlin and Leipzig by the leading bacteriologists of Germany the ordinary inks literally teem with bacilla of a dangerous character, the bacteria taken therefrom sufficing to kill mice and rabbits inoculated therewith in the space of from one to three days."* * * * * * * *

"The most easy and neat method of forming letters of gold on paper, and for ornaments of writing is, by the gold ammoniac, as it was formerly called: the method of managing which is as follows:

"Take gum ammoniacum, and powder it; and then dissolve it in water previously impregnated with a little gum arabic, and some juice of garlic.

The gum ammoniacum will not dissolve in water, so as to form a transparent fluid, but produces a milky appearance; from whence the mixture is called in medicine the lac ammoniacum. With the lac ammoniacum thus prepared, draw with a pencil, or write with a pen on paper, or vellum, the intended figure or letters of the gilding. Suffer the paper to dry; and then, or any time afterwards, breath on it till it be moistened; and immediately lay leaves of gold, or parts of leaves cut in the most advantageous manner to save the gold, over the parts drawn or written upon with the lac ammoniacum; and press them gently to the paper with a ball of cotton or soft leather. When the paper becomes dry, which a short time or gentle heat will soon effect, brush off, with a soft pencil, or rub off by a fine linen rag, the redundant gold which covered the parts between the lines of the drawing or writing; and the finest hair strokes of the pencil or pen, as well as the broader, will appear perfectly gilt."It is usual to see in old manuscripts, that are highly ornamented, letters of gold which rise considerably from the surface of the paper or parchment containing them in the manner of embossed work; and of these some are less shining, and others have a very high polish. The method of producing these letters is of two kinds; the one by friction on a proper body with a solid piece of gold: the other by leaf gold. The method of making these letters by means of solid gold is as follows:

"Take chrystal; and reduce it to powder. Temper it then with strong gum water, till it be of the consistence of paste; and with this form the letters;and, when they are dry, rub them with a piece of gold of good colour, as in the manner of polishing; and the letters will appear as if gilt with burnisht gold."(Kunckel, in his fifty curious experiments, has given this receipt, but omitted to take the least notice of the manner these letters are to be formed, though the most difficult circumstance in the production of them.)