| 110 | lbs. | flint batch, |
| 1 | " | oxide of uranium, |
| 2 | oz. | carbonate of copper. |
OPAL.
| 500 | lbs. | batch, |
| 60 | " | phosphate of lime, |
| 4 | " | arsenic, |
| 20 | " | nitrate of soda. |
Said to turn without cooling.
William Gillender, of England, gives the following receipt for Bohemian Red, or Ruby:—
| Sand, | 62 | lbs. |
| Lead, | 76 | " |
| Nitre, | 22 | " |
| Antimony, | 8 | oz. |
| Manganese, | 3 | " |
Add one ounce of purple of Crassus to every eighty pounds of the above batch.
WAX RED.
| To | 15 | lbs. | flint batch add | |
| 1 | " | raw brass, | ||
| ¾ | " | crocus martus. | ||
This he says is very good.