VOL. XVI.] FHILOSOPHICAL TRANSACTIONS. 275 



brought from India : a kind of mud adhering to the froth about reeds, and which 

 when tried with a coal, the true burns with a purple-flame, and smells of the 

 sea : Linschoten says, it is called anil, that it grows in Camaia, and is a plant 

 like rosemary, which is gathered atid dried, then wetted with fair water, and 

 beaten to a mud; this operation being repeated, it is dried and fitted for use.* 

 7. Indian ink; its use known to Pliny, though not its composition ; which is 

 yet undiscovered, except it should be burned rice, as has been thought. The 

 yellows and reds made use of, are these that follow. 



I. Cerusse is the rust of lead, made by a vaporous calcination ; Pliny write* 

 thus of it in the 34 lib. cap. 18. Cerusse, or psmythian, is made in the plum- 

 mers' shops of small plates of lead laid upon each other on a vessel of very strong 

 vinegar ; what falls into the vinegar is taken out, and dried in the sun : and he 

 says it was made at Rome of burned marble flint, quenched in vinegar. 

 2. Masticot is a kind of improper calx of tin.-l- 3. Gutta gambae, or gambodia, 

 the inspissated juice of a plant, not well known;;}: it comes from the [East] Indies. 

 Some think it the juice of euphorbium ; others scammony, or tithimal ; others 

 ricinus ; others refer it to the greater cataputia, esula, or the flowers of the 

 Indian ricinus, and will have it coloured with turmeric. 4. Ochre, a kind of 

 njitural earth. There are two sorts ; the one native, formerly brought out of 

 Attica, now from Dacia and Hungaria, and from many places of England, 

 especially in the forest of Dean : the other a factitious substance of lead, burned 

 and quenched in vinegar. In Pliny's time it was made of rubrica, or reddld 

 burned. 5. Orpiment, a fat inflammable mineral, justly ranked among poisons, 

 for its extreme corrosive quality. Pliny says it was dug up in Syfia on the sur- 

 fece of the earth ; and that the Emperor Caligula had hopes of getting gold out 

 of it; hence he caused 14 pounds of it to be tried, which aftbrded him very 

 good gold, but in so small a proportion, that he lost by the trial. ^ 6. Umber 

 is a native earth. 7- Red-lead, a colour unknown to the ancients, made of li- 

 tharge or burned lead, by a reverberatory calcination, or of cerusse put in 8 

 platter over the fire ; which must be continually stirred till it has acquired a red- 

 lead colour. 8. Burned ochre is the common yellow ochre burned in the open 

 fire. Q. Cinnabar or vermillion. There are two sorts ; native, or the minium 

 of the ancients, which is the mineral that yields quicksilver ; of which and of 

 sulphur it chiefly consists. It is found in the mines of Istria. This colour was 

 among the ancient Romans used to sacred purposes ; and on festivals, Jupiter's 



* Indigo is DOW *ell known to be a sort of fecula extracted from the plant termed indigofera 

 tinctoria. 



+ Masticot is a calx of lead. 



t Gamboge is a gum-resin obtained from a tree denominated by botanists stalagmites cambogioides. 

 § Orpiment ii a connp6und of sulphur and arsenic. 



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