Writing Ink.
The ancient writing ink was a viscid mass like painter’s colours, and therefore letters in ancient manuscript frequently appear in relief.[71] Pliny’s writing ink is mentioned by Dr. Bancroft, according to whom it consisted of the simple ingredients in the following receipt. “Any person who will take the trouble of mixing pure lamp black with water, thickened a little by gum, may obtain an ink of no despicable quality in other respects, and with the advantage of being much less liable to decay by age, than the ink now in common use.” It should be observed, however, that every black pigment mixed with gum or size can be soon and easily washed out again with water.
It is not purposed to make this a “Receipt Book,” yet, as connected with this subject, two or three really good receipts may be of essential service, at some time or other, to many readers. For instance, artists, and other individuals who require it, may easily manufacture a black pigment in the following manner, with a certainty of its being genuine, which can scarcely be placed in the article sold at most shops.
A pure Lamp Black.
Suspend over a lamp a funnel of tin plate, having above it a pipe to convey from the apartment the smoke which escapes from the lamp. Large mushrooms of a very black carbonaceous matter, and exceedingly light, will be formed at the summit of the cone. This carbonaceous part is carried to such a state of division as cannot be given to any other matter by grinding it on a piece of porphyry. This black goes a great way in every kind of painting. It may be rendered drier by calcination in close vessels; and it should be observed that the funnel ought to be united to the pipe, which conveys off the smoke, by means of wire, because solder would be melted by the flame of the lamp.[72]
Receipts for Ink.
Chaptal the eminent chemist, after numerous experiments regarding writing ink, concludes, that the best ingredients and proportions are the following, viz: two parts of galls, in sorts, bruised, and one part of logwood chipped; these are to be boiled in twenty-five times their weight of water for the space of two hours, adding a little water from time to time, according to the evaporation. The decoction so made, he says, will commonly mark from 3 to 31⁄2 degrees upon the hydrometer of Beaumé, equal to about 1022 of the common standard. At the same time a solution of gum arabic is to be made with warm water, until the latter will dissolve no more of the former. This solution will mark 14 or 15 degrees, equal to about 110. A solution of calcined sulphate of iron is also to be made, and concentrated so that it will mark 10 degrees, equal to about 1071. And to this as much sulphate of copper is to be added as will be equal to one-twelfth part of the galls employed to make the decoction. The several matters being so prepared, six measures of the decoction are to be mixed with four measures of the solution of gum; and to this mixture from three to four measures of the metallic solution are to be added, by a little at a time, mixing the several matters each time by shaking. Ink so made, will, he says, form no sediment: and he estimates the proportions of solid matters contained in it to be five hundred parts of gums, four hundred and sixty-two parts of the extract of galls and logwood, and four hundred and eighty-one parts of metallic oxides.
Dr. Bancroft, who gives these particulars from Chaptal, proposes the following, as being generally the most suitable proportions for composing the best and most lasting writing ink, viz:
Take of good Aleppo galls, in sorts, coarsely powdered, twelve ounces, and of chipped logwood six ounces; boil these in five quarts of soft water two hours, and strain off the decoction whilst hot; then put to the residuum as much boiling water as, when properly stirred, strained, and added to the former, will suffice to make the whole of the decoction equal to one gallon; add to this five ounces of sulphate of iron, with the same quantity of gum arabic, and two ounces of good dry muscovado sugar; let these be all dissolved, and well mixed by stirring.