Young's Demonstrative Translation of Scientific Secrets by Daniel Young
page 87 of 236 (36%)
page 87 of 236 (36%)
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sometimes a little chloride of silver previously melted with flux
No. 3. If the purple, when prepared, does not melt sufficiently easy, some flux may be added when it is dry. 246. DEEP VIOLET The purple of Cassius, in place of flux No. 3, flux No. 1 is mixed with it. Sometimes a little of blue No. 233 is added. 247. FLESH RED The sulphate of iron, put in a small crucible, and lightly calcined, produces a suitable red oxide. Those which have the desired tone are selected. All the flesh reds are made in this way, and vary only in the degree of heat which they receive. 248. HAIR BROWN Yellow ochre, No. 244, 15 parts; oxide of cobalt, 1 part; well triturated and calcined, in order to give the tone to it. 249. LIVER BROWN Oxide of iron made of a red brown, and mixed with three times its weight of flux No. 2. A tenth of sienna earth is added to it if it is not sufficiently deep. |
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