It must be observed, that in all the foregoing operations, it will be requisite to add sonic sort of siccative. A very gene ral and useful one is made by grinding in linseed, or, per haps, prepared oils, boiled, are better, about two louts of the best white copperas, which must be well dried, with one part of lithargo of lead ; the quantity to be added will much depend on the dryness or humidity of the at the time of painting, as well as the local situation of the building.
it is highly proper here to observe, that there is a kind of eopperots made in England, and said to be used fin• some purposes in medicine, that not only does not assist the opera tion of drying-in the colours, but absolutely prevents those colours drying, which would otherwise have done so by them selves. The best dryer for all line whites, and other delicate tints, is sacehartnn sat urni, or sugar of lead, ground in nut oil ; but which being very active, a small quantity. about the size of a walnut, will be sufficient for twenty pounds of colour, where the basis is ceruse. It will be always worthy to be observed, that the greatest care should be taken to keep all the utensils, brushes, &c., particularly clean, or the colours will soon become very foul, so) as to destroy the sur face of the work. If' this should so happen, the colour should be passed through a fine sieve, or canvass; and the surthee of the work be carefully rubbed down with sand-paper, or pumice-stone ; and the latter should be prepared by being ground in water, if the paint be tender, or recently laid on.
The above may suffice as to painting on wood, either on outside or inside works; the former being seldom finished otherwise than in oil, four or five coats are generally quite We shall now proceed to note what is requisite for the painting of new or stucco, not painted before and pre pared tor 011-cOl0lIPS.
It does not appear that any painting in oil can he done to any good or sersieeable effect in stucco, unless not merely the surrave appear dry., but that the walls have been erected a suflivient tune to permit the mass of brickwork to have acquired a sufficient degree of dryness: when stucco is on battened work, it may be painted over much sooner than when prepared as brick. Indeed, the greatest part of the mystery of painting stucco, so as to stand or wear well, certainly con sists in attending to these observations ; for whoever has observed the expansive power of water, not only in eonge lation, but also in evaporation, must be well aware that when it meets with any fiireig,n body obstructing its escape, as oil paintings for instance, it immediately resists it ; forming a number of vesicles, or particles, containing an acrid lime water, which tbrces off the layers of plaster, and frequently causes huge defective patches extremely difficult to get the better of Perhaps, in general cases, where persons are building on their own estates, or for themselves, two or three years are not too long to suffer the stucco to remain unpainted ; though frequently, in speculative works, as many weeks are scarcely allowed. Indeed, there are some nostrums set forth in fitvour of which it is stated, in spite of all the natural properties of bodies, that stucco may, after having been washed over with these liquids, be painted immediately with oil-colours. It is
true tWre may be instances, and in many experiments some will be found, that appear to counteract the general laws of nature; but, on following them up to their causes it will be found otherwise.
Supposing the foregoing precautions to have been at tended to, there can be no better mode adopted for priming on la ing on the first coat on stucco, than by linseed or nut oil, boiled with dyers, as before mentioned, with a proper brush ; taking care, in all cases, not to lay on too much, so as to render the surface rough and irregular, and not more than the stucco will absorb. It should then be covered with three or four coats of cernse, or white lead, prepared as described for painting on wainscoting ; letting each coat have sufficient time to dry hard. If time will permit, two or three days between each layer will not be too long.
If the stucco be intended to be finished of any given tint, as gray, light green, apricot, &c., it will then be proper, about the third coat of painting, to prepare the ground for such tint by a slight advance towards it.
Gray is made with ceruse, Prussian blue, ivory black, and lake ; sage green. pea, and sea greens, with white, Prussian bine, and fine yellows ; apricot and peach, with lake, white, and Chinese vermilion; fine yellow ffissm colour, with burnt terra Sienna, or umber, and white ; olive greens, with tine Prussian blue and Oxfordshire ochre.
Painting in distemper, or water-colours mixed with size, stucco, or plaster, which is intended to be painted in oil when finished, but not being sufficiently dry to receive the oil, may have a coating in water-colours, of any given tint required, in order to give a more finished appearance to that park of the building. See DISTEMPER FRESCO.
Straw colours may be made with French white. ceruse, and masticot. or Dutch pink. Grays. fine, with some whites, and refiners' verditer. An inferior gray may be made with blue-black, or bone-black, and Pwi-greens, with French green, Olympian green, &c. Fawn colour with burnt terra de Sienna, or burnt umber and white: and so of any intermediate tint. The colours should all be ground very fine, and incorporated with white, and a size made of parch ment, or some similar substance ; isinglass being too ex pensive for common works.
It will not require less than two coats of any of the fore going colours in order to cover the plaster, and bear out with a uniform appearance. It must be recollected, that when the stucco is sufficiently dry, and it is desirable to have it painted in oil, the whole of the water-colour might to be removed ; which may be easily done by washing ; and when quite dry, proceed with it after the dl-rections given in oil painting of stucco.
When obi plastering has become discoloured by stains, and it is desired to have it painted in distemper ; it is then ad visable to give the old plaster, when properly- cleaned off and prepared, one coat at least of white lead ground in oil, and used with spirits of turpentine, which will generally fix all old stains ; and when quite dry, will take the water colours very kindly.
The above processes will also apply to old wainscoting, in cases where temporary painting is only required ; but cannot be recommended for durability.