384 Campari/on between the Human Race and Swine, 



All artifts who fpeak of the ufe of Naples yellow, give cau- 

 tions againft applying iron to it, as the colour by thefc 

 means becomes grecniih, or at leaft dirty. For this reafon, 

 it muft be pounded on a (tone, and fcraped together with 

 an ivory fpatuia. It is employed chiefly in oil painting, be- 

 caufe the colour is fofter, brighter, and richer than that of 

 ochre, yellow lead, or orpiment, and becaufe it far exceeds 

 thefe pigments in durability. It is employed in particular 

 when the yellow ought to have the appearance of gold, and 

 in this refpect it may be prepared with gum water and tiled 

 as a water colour. A. (till greater advantage of it is, that it 

 i» proper for enamel painting, and on that account may be 

 employed on porcelain or earthen ware *. In the laft place 

 I would recommend to artifts to examine whether the oxyd 

 prepared from wolfram, by boiling in the muriatic acid, 

 which has a beautiful yellow colour, might not be ufed in 

 the fame manner as Naples yellow f. 



IX. Companion fietteern the Human Race and that of Swine. 

 J>r I.F. Br.u menu ach. From Magazin far das Neueftc 

 4US der Phyfik. Vol. FI. 



IOME late writers on natural hi (lory feem doubtful whe- 

 ther the numerous diitinot races of men ought to be consi- 

 dered as mere varieties, which have arifen from degenera- 

 tion, or as ft) many fpecies altogether different. The caufe 

 of this feenis chiefly to be, that they took too narrow a view 

 in their refearcbesj fclected, perhaps, two races the mod 

 different from each other poihble, and, overlooking the inter- 

 mediate races that formed the connecting links between 

 diem, compared thefe two together; or, they fixed their 



* Injhc Memoirs of the Academy of Sciences for 1767 Fougeroux has 

 proved that the giailolino prepared by him produced on porcelain a much 

 more beautiful colour than the Naples yellow fold in the fliops. 

 \ Gmelm's Tcchnifche Ckemie, pi^. 



attention - 



