DURING THE MIDDLE AGE. 125 



in 1571, and John Jcnitz. and Jofeph Harrcn, 

 followed his example, in 1575, in Saxony. In 

 the year 1564, David Hcidler, in Bohemia, and 

 Hicr. 7,urch in Mifnia, had already found pro- 

 ccfies for collecting arfcnic from them. 



From the paintings in Hcrculancuin we fee, 

 that all the colours that arc prepared with wa- 

 ter were known long before the year 79. With 

 thcfe the ancients painted on walls frefh plaifter- 

 cd. The art of mixing colours with oil, it is com- 

 monly believed, was invented by John Von 

 Bruggcs, about 1431; though it is fuificient- 

 Iy evident that it was pradiifcd in the nth 

 century. 



Very little improvement w f as made in the art 

 of dying, for many ages from the beginning of 

 this period. The Greeks and Saracens of Eu- 

 rope ufcd the purple of the Weft ; but at length 

 this colour fell into difcflccm, and the more 

 brilliant red was preferred : In fo much that, 

 in the nth century, the fccrct of ftaining with 

 the purple periflicd likewife in the Eaft. By the 

 expeditions of the crufades, many artifls,and with 

 them various arts found their way into Italy ; 

 and the chief of them took up their residence 

 at Venice, to which port moil of the vcileis 

 from the Eall rcforted. As early as the year 

 1194, 1198, and 1306, mention is made of the 

 grana dc brafilc, braxitts, and indigo : Though 

 they certainly did not mean thofc fubAaru.c^ 



which 



