74 LECTURE X. 



the occasional addition of other oily and resinous substances. The work 

 may be executed on wood, cloth, silk, paper, marble, or metals : these sub- 

 stances being first washed with size, and then primed with an oil colour, 

 which is usually white, but sometimes dark. Some painters have, however, 

 preferred a ground of distemper. The glare of the oil colours or of the var- 

 nish, which is added in order to give them brilliancy, is considered as an 

 inconvenience attending oil paintings ; and some of the colours are too 

 liable to fade or to blacken by the effect of time. 



The encaustic paintings of the ancients were imperfect approximations 

 to the art of painting in oil. Wax or resins were employed for retaining 

 the colours in their places ; and they were applied by means of a moderate 

 heat.* An effect nearly similar is produced by dissolving the resins in 

 spirits of wine, as is done in painting in varnish. A much greater degree 

 of heat is required for paintings in enamel : for this purpose the colours are 

 mixed with a glass of easy fusion, and, when finely powdered, they are 

 usually applied with oil of turpentine, or sometimes oil of lavender, to a 

 ground of metal or porcelain ; they are afterwards fixed and vitrified by 

 exposure to the heat of a furnace. 



Mosaic work is performed by putting together small pieces of stone or 

 baked clay of various colours, so as to imitate the effects of painting ;t in 

 tapestry and in embroidery, the same is done by weaving, or working in 

 threads of different kinds. 



The art of writing is of great antiquity, but it is probably in all coun- 

 tries, and certainly in some, of a later date than that of drawing represent- 

 ations of nature. The Mexicans, at the first arrival of the Spaniards in 

 South America, are said to have employed drawings as a mode of conveying 

 intelligence : some of them simply resembling the objects to which they 

 related, others intended as hieroglyphics ; that is, like the ancient Egyptian 

 characters, of a nature intermediate between drawing and writing.;}; The 

 Chinese have always used arbitrary marks to represent whole words or the 

 names of external objects, not resembling the objects to which they relate, 

 nor composed of letters appropriated to constituent parts of the sound, 

 although they are said to be combined from a few hundred radical charac- 

 ters expressive of the most simple ideas. The art of writing with alpha- 

 betical letters must have been sufficiently understood in the age of Moses, 

 to serve the purpose of the promulgation of laws and of religion ; it is 

 generally supposed to have been invented by the Phenicians. Among the 

 Greeks it was in a very imperfect state until the time of the siege of Troy, 

 or about 3000 years ago. The Chinese- write from above downwards, 

 beginning on the right side ; the other eastern nations have always written 

 from right to left. The most ancient Greek inscriptions are turned alter- 

 nately backwards and forwards, the letters being reversed in the lines 

 which begin on the right side ; but the Greeks soon confined themselves to 



* Pliny,!. 35, c. 11. Vitruvius, Architectura, 1. 7, c. 9, de Minii Temperatura. 

 Colebrooke, Ph. Tr. 1759, p. 40. Caylus on Encaustic Painting, Lond. Fabbroni 

 on Do. Ph. M. i. 23, 141. Gilbert's Annalen, v. 357. 



t Ph. Mag. ix. 289. 



t See the plate of Aztec Chronology from Carreri, in Encyc. Metr. vol. xix, pi. 

 28. Robertson's Hist, of America, ii. 284, 480. Humboldt, Voyage de Cordilleras. 



