mixture of soot, glue, camphor, and musk. The best 

 varieties of this pigment are made in China, and the 

 exact process of its manufacture is still a secret. It is 

 quite possible that the quality of the product is due 

 to the method of manipulating the ingredients rather 

 than to the quality of the ingredients themselves. By 

 some it is thought that the superiority lies in the material 

 from which the soot is made, or that it is made from a 

 substance not readily obtainable in the West. It has 

 been suggested, for example, that the soot may be made 

 from the wood of the camphor tree, and that this is 

 peculiarly adapted for making this particular pigment; 

 but it seems more reasonable to suppose that it is the 

 method of making, rather than the material contained, 

 that makes the Chinese ink superior to the European. 



WHITE PIGMENTS 



White lead is one of the oldest known pigments. The 

 Romans manufactured it and used it in great quanti- 

 ties, and the name they gave it, cerussa, is still used in 

 commerce. It is known also as flake white, Dutch 

 white, Venetian white, Krems white, and by a score of 

 other names. 



Chemically, white lead is a basic lead carbonate 

 that is, a compound of lead carbonate and lead hy- 

 droxide; and commercially it is supposed to be this 

 substance. In point of fact, however, it is found in the 

 /market adulterated with all manner of different sub- 

 stances. Indeed, there are probably few commercial 

 products that lend themselves so temptingly to adul- 



[274] 



