From the 14th century onwards, the treatises, or rather probably composite transcripts from earlier treatises, multiply greatly; so far, however, as I have been able to make out from the able analysis made by Sir C. Eastlake, Mr. Hendrie, and Mrs. Merrifield, of many, they contain little more information than is conveyed in the extracts already given. Some curious details, however, may be gathered as to the London practice in the 15th century, which may interest the reader. A manuscript, written in German, as is believed at that date, is preserved in the public library at Strasburg, which distinctly proves that the colours for illuminating were commonly preserved by steeping small pieces of linen in the tinted extracts, sometimes mixed with alkaline solutions. The process is minutely described in this MS.; the dyes so prepared are there called "tüchlein varwen," literally "clothlet colours." The following passage from another compendium, a Venetian MS., gives the result in few words:—"When the aforesaid pieces of cloth are dry, put them in a book of cotton paper, and keep the book under your pillow, that it may take no damp; and when you wish to use the colours, cut off a small portion [of the cloth], and place it in a shell with a little water, the evening before. In the morning the tint will be ready, the colour being extracted from the linen." This practice is alluded to by Cennini, when he says:—"You can shade with colours, and by means of small pieces of cloth, according to the process of the illuminators."
The German compiler, speaking of the preparation of a blue colour in this mode, says, "If you wish to make a beautiful clothlet blue colour according to the London practice," &c. After describing the method of preparing it, he adds:—"These [pieces of cloth] may be preserved fresh and brilliant, without any change in their tints, for twenty years; and this colour, in Paris and in London, is called [blue] for missals, and here in this country clothlet blue; it is a beautiful and valuable colour."
"The place denominated Lampten, mentioned together with Paris, can be no other than London."[[113]]
As pursuing the subject of ancient processes further than I have now done, would scarcely he profitable to the student, I proceed to the second division of this part of my subject, and accordingly take up the modern processes. In offering the following details on this subject, however, to the amateur's attention, I would not for one moment let it be supposed that a knowledge of them alone will be sufficient to make him an efficient illuminator. Fortunately many very excellent artists have of late devoted themselves to giving instruction in the practical manipulation of the art, and amateurs cannot do better than place themselves at once in communication with masters, whose addresses may be obtained at the shops of the principal artists' colourmen. There will still be, no doubt, in different parts of the country, many desirous of illuminating, and yet unable to obtain the benefit of seeing a practised hand work before them, or even to pick up information as to the modus operandi. To such, at least, the following observations may prove useful.[[114]]
The two great sections into which all the processes by which illumination of any kind may be executed, divide themselves, are—1st, those in which water and glutinous substances soluble in water form the vehicles for applying the pigments, and causing them to adhere to the surfaces on which they may be applied; and 2ndly, those in which oil or spirit, and resins, or other substances which combine readily with such fluids, are made to perform corresponding functions. The pigments, reduced to an impalpable powder, are the same in both classes of processes, which are commonly known as watercolour-painting and oil-painting. That which was of old the artist's greatest stumbling-block—the manufacture and preparation of his pigments—need now no longer occasion him the slightest embarrassment; for every colour with which his palette could be enriched is to be bought, ready prepared, of the principal artists' colourmen. In like manner every other essential for his use is now freely at his command; and all that is required on his part is knowledge how to employ the materials which others most dexterously and carefully place at his disposal.
In commencing the collection of that information which I am now endeavouring to communicate, I felt it my duty to enter into correspondence with all those manufacturers whose products I had at different times personally tested; and I accordingly addressed myself to the following, whose materials, with insignificant exceptions, I have invariably found satisfactory, both in nature and quality.
R. Ackerman, 191, Regent-street, W.
L. Barbe, 60, Quadrant, Regent-street, W.
J. Barnard, 339, Oxford-street, W.
Messrs. Brodie & Middleton, 79, Long-acre, W.C.