The expedient recommended under Art. the second, for establishing a standard for all the differing principal tints that may be required for any subject, will be of use to them who are not much acquainted with painting in water colours; and to ladies and gentlemen, who painting only now and then for their amusement, cannot have so thorough a knowledge of the value of each colour, and might therefore be at a loss how to retouch, after the colours are fixed.
To make the directions given for that purpose more intelligible, and to point out the use of such a standard—let us suppose—the annexed copper plate figure A. B. C. D. to be a piece of cloth, about a foot long and three or four inches wide, waxed on the back, as directed under Art. the first, and the divisions a. b. c. d. e. f. g. h. &c. be the tints painted, according to their order and degradation, across the whole width of the cloth A. B. these tints dry, cut the piece of cloth across all the tints from top E. to bottom F. in two equal parts, bring the one half A C near the fire, and by melting the wax fix it, the other half B D you keep as it is unfixed.
Now, the half A C being fixed, will shew you at one glance what strength every tint will acquire; and if you moisten again the other half B D, or paint the same tints upon a fresh piece of cloth, you will see which are the colours that grow deeper still, fixed with wax than they appear when only moistened with water, and the references 1 2 3 4 5 &c. telling you what each tint is composed of, you will be enabled to amend any one that might be amiss. Farther, when your picture will be fixed and it should want retouching, and you should be at a loss for hitting of the tint or hue required for that purpose,—bring only the fixed half A C upon the picture and compare them, and you will easily find what you want; again, if you want to renew any tint that is spent, find that tint upon the picture, with the fixed half A C, when found compare it to, and moisten its fellow upon the unfixed half B D, and that will give you again the original hue, and the references 1 2 3 4 &c. will tell you what that tint is principally composed of.
Tho’ professed artists (whose long experience enables them to judge of the value of each colour) will not have absolute occasion for the comparative use of such a standard, yet they will not do amiss to make an essay of their tints before they employ them.
Observations on Article the third.
The being able to work and retouch at pleasure, and at any time, without fatiguing the colours, or any other detriment arising from it, is an advantage peculiar to encaustic only; for, the new colours will unite with the old ones without making spots, as is the case in common size-painting; nor will there be that inconveniency of rubbing the places to be retouched over with oil, as is the case with oil pictures; the only seeming difficulty to a beginner, will consist in the colours growing paler and weaker in drying, but as a picture is easily kept wet, by moistening it now and then as above directed, the difficulty vanishes. Pictures of any size may easily be kept wet for several days, by applying a double wet cloth on the back; but a little practice will render that precaution unnecessary.
Every body in the least acquainted with colours, knows that water colours, tempered or employed either with gum or size, grow paler and lighter in drying, and that they acquire their true tone only when dry;—in encaustic they grow paler and lighter too in drying, but they recede from and lose their true tone.—Encaustic is the reverse of size-painting as to effect, while you are at work and the colours wet;—of the latter you cannot judge positively until the colours are dry; of the former you can only judge while the colours are wet, or which is the same, when fixed with the wax.
Observations on Article the fourth.
The most essential point in encaustic—the fixing of the colours—is the simplest and easiest for paintings of any size, moveable or immoveable. A surface of forty feet may be fixed as conveniently as a picture of twelve inches; for if the painting be too large to be brought near the fire, or immoveable on a wall, bring that agent to the painting;——a square copper or iron chest, or box, such as commonly used for warming or airing of beds, with a red hot iron or lighted charcoal in it, will do the business admirably well, by passing it in a direction parallel to and before the painted surface, at a distance proportionable to the degree of heat it casts,—a brasier ambulant, with a cover to prevent the ashes from flying about, with charcoal well lighted, will answer the end too, by inclining the picture over it,—an instrument of iron like a baker’s shovel, with a long handle and made red hot, will perform the same service, if waved in a parallel direction before the painted surface; and by heating it again, when grown cool, with such an instrument one may fix paintings of the largest size; it matters not if the whole be fixed at once, or in parts at different times.