Mfcmolf en a Method ofHoufe Pal/iftng, ' 5^ 



The preceding Infl:ru£Hons have been fuiEcieBt for moft of thofa who haye made ufe of 

 this painting ; but let us reafon upon it, and difcufs the theory which has guided me in 

 the choice and combination of thefe ingredients; 



• In the firft place, let us fpeak of painting in diftemper. This is done, as every ohc 

 knows with fize, to which is added Spanifli white, or ochre. 



Its inconvenicncies are numerous'.-''"^'- '. •' •'- 



In the firft place it comes off by the flighteft friflion; fo that for the moft part It is an 

 Inconvenience to fuffer the clothes to come in contadl with the walls and paflages painted 

 in this manner. 



It is true that this inconvenience is remedied by ufing ftronger flze, and laying on a 

 greaternumber of coatings ; but in this cafe, in the eourfe ef time, in dry expofures, the 

 painting peels off", and is detached. ,• ; i-^ ■ 



It is no trifling confideration, that three coatings in diftemper will coft thirty fous, or 

 n^ar feven times as much as our paint of three coatings, if that were neceflary. 



The confequences where the expofure is moift are ftill more pernicious. The glue or 

 flze which forms the bafis of diftemper becomes moift, and ferments ; like every other 

 animal glue it partly paffes to the ftate of acidity ; it oeafes to be glue, and is no longer 

 adhefive ; it becomes a fluid and acid water, which fpeedily acquires the putrid ftate. It 

 is more particularly at the time of thaw that this effedt of moifture becomes very fenfible, 

 and then the paint of this defcription is feen to flow in ftrcaks along the walls and wood 

 work. The earth and ochre becoming feparated from the gelatinous fubftance, are then 

 abandoned to their pulverulent ftate, and the paint falls off. 



This dlfpofition of animal gluten to attraft moifture from the air, and to ferment, ex- 

 plains the reafon why in procefs of time painting In diftemper emits a fmell, unlefs it be 

 varniflied, which partly remedies thofe inconveniencies ; but at the fame time it muft be 

 fecollefted, that it adds to the expence. 



We muft alfo remark, that the mixing of the fize colour requires a fire, and demand? 

 thecxpenceof workman's time during part of the morning for its preparation : and that 

 laftly, this paint will not keep, but frequently changes in the eourfe of twenty-four hours, 

 particularly in ftormy weather. .' , 



On the other hand, let us confider and compare our method of painting. 



Skimmed milk has loft its butyraceous part, but It keeps Its cheefy part or curd, of 

 which milk contains more or lefs, at a medium about one fourth in a ftate of ftrong gela- 

 tine; confequently there is about a pound in the Paris pint, or four pounds of milk, which 

 is our proportion. I fay in the ftate of gelatine, for the cafeous part not being foluble in 

 water is not gelatine, but it is glue. 



We have therefore one pound of glue, which deferves the name of ftrong glue, in pre- 

 ference to the glues which are fo called, and this is appropriated to give body to our 

 toi^urs ; but this glue of milk has great advantages over the common animal glue. 



Vol. v.— October. i8oi. K k The 



