*3 0)t JLncaujTic Painting. 



mere wafhing may be prejudicial to an old painting ; and that 

 the method of reuefhing paintings, as it is called, by daub- 

 ing over the furface from time to time with new drying oil, is 

 highly prejudicial and ill calculated for the intended purpofe, 

 fincethe oil when it becomes dry contracts in its whole fur- 

 face, carries with it the paint under it, and occafions cracks 

 in the painting. New oil of flits kind gives occafion to mi- 

 neral paints to be reftored ; but covers the picture with a 

 new coat of refin, and then of carbon, which arifes from the 

 gradual combuftion, and always caufes more blacknefs, and 

 the decay of the painting which one wifhes to prefervc. 

 Wax, on the other hand, undergoes a change which is very 

 different from that of drying oil. The wax, inftead of be- 

 coming black by the contact of the atmofphere, increafes in 

 whitenefs, and, according to its natural quality, is not decom- 

 pofed in the air, and it does not ftrongly attract the oxygen 

 of the calces or metallic allies which arc commonly ufed in 

 painting. Moreover, the fo called earths, which are in them- 

 felves white, and are never variable either by the prefence or 

 abfence of oxvgen, cannot be employed in oil-painting, be- 

 caufe that fluid makes them almoft traniparent, and caufes 

 them to remain as it were without body {corpo), and not to 

 produce the withed-far effect. That beautiful white, which 

 may be obferved on the before-mentioned Egyptian encauf- 

 tic, is nothing elfe than a fimple earth, and according to 

 my chemical experiments a chalk (creta,) which is alfo un- 

 alterable. If we confider this encauitic fragment as belong- 

 ing to the epoch of the firft violent change which the reli- 

 gious fyliem of the Egyptians experienced, it will be a fpeci- 

 men of painting of about -500 years old; for fuch is the 

 number of the years that have elapfed fince Cambyies over- 

 turned the ceremonies and religious worlhip of the Egyp- 

 tians, not only by the fword, but by the ftill more powerful 

 weapons of ridicule. Dead bodies were embalmed there in 

 the time of Herodotus ; but the cloth in which they were 

 wrapped, or the bandages bound round them, were no longep 



painted 



