Memoir on a Method of tJoufe Patntlng. .2<^I 



The pitch Is to be melted by a gentle heat in the oil, and then added to the fmoolh mix- 

 ture of milk and lime. In cold weather this mixture ought to be warmed, in order that it 

 may not occaGon too fpeedy cooling of the pitch, and to facilitate its union with the milk 

 of lime. This paint has fome analogy with that known by the name of encauftic. 



I have employed this compofition for outfide fliutters, formerly painted with oil. 



The common method of painting in oil, though thought to be fo durable, participates 

 ftrongly in the inconveuiencies of painting in diftemper ; that is to fay, it (brinks, cracks, 

 fcales off, and is feparated ; with this; difference, that the flakes preferve fome points of 

 adhefion. But is not the lefs true, that the wood remains uncovered, and expofed with* 

 out defence to the a£tion of the air. i 



For the fake of neatnefs, it is proper to rub down the furface with fand ftone, or 

 pumice ftone, before the firft coating is laid. on. 



Time, which deftroys every thing, will deftroy this paint ; but I do not in theory fee 

 any reafon why the adhefion of the refinous milk paint ffiould break, or that it (hould crack 

 and fcale off like the painting in oil ; of which the bafe is cerufe, a preparation of lead, 

 which renders the oil drying, and difpofes this kind of paint to crack. This metallic fub- 

 ftance has alfo the Inconvenience of becoming coloured in the air by the aQion of hidrogen 

 gas ; fo that white paint becomes yellow, and is frequently covered with black fpots by a 

 de-oxidation affumed by the oxide of lead. The exhalations of a drain or neceffary, or the 

 vicinity of a ftable, are fufficient completely to blacken painting of lead colour with oil. 



There is no lead in the paint of refinous compofition with milk, confequently this incon- 

 convenience is not to be feared. The air cannot change the colour of this pa:nting, as I 

 am convinced by experience in my hot-houfe -, and every building of this defcription is 

 expofed to the exhalation of fermenting vegetable fubftances. 



I need not mention the unwholefome fmell of oil painting, nor the long time it conti- 

 nues. In country houfes which are not Inhabited during winter, it is found to remain 

 even for feveral years fucceffively. The dangers of the exhalation of this kind of paint arc 

 frequent, and but too well known. 



Our painting with refinous compofition and milk, notwithftanding the oil and the Bur- 

 gundy pitch which enter into its compofition, emits no other fmell than that of turpentine * i 

 a fmell which is fpeedily diffipated in a day or two, befides which it is ufed only for out- 

 door work. 



The reafons are flronger in favour of fubftituting either of thefe new modes of painting, 

 to that which is called Z-a^/Z^ww t. This pigment confifts of quick-lime, yellow ochre, and 

 water ; it lafts very well within-doors, but when expofed to the air It foon difappears< 

 This mixture has no confiftence; its adherence to ftone Is fo weak, that the rain carries it 

 off, and leaves no trace in two or three years. 



• It is well known that Burgundy pitch is the refidue of diftillation of turpentine with water, an opera-' 

 fion for the purpofe of feparating the volatile oil. 

 •f We have no appropriate niuiie in Englifli for this method, 



Kka This 



