Sometimes, when using potash, M. Gautier has mixed nitre with it, and has always obtained a richer product than when potash alone had been employed.—Jour. de Phar. 1827, p. 11.
19. Sulphocyanide of Potassium in Saliva.
20. Decomposition of Sulphate of Copper by Tartaric Acid.
21. Separation of Arsenic from Nickel or Cobalt.
The method of freeing cobalt from arsenic, is the same as for nickel; but it is then necessary to perform the operation a second time. The cobalt (that of Tunaberg) has never been perfectly freed from arsenic by one operation, but has never retained any after the second.—Archiv für Bergbau, 1826, p. 186.
22. Compounds of Gold.
| 1 atom gold | 25 |
| 3 " oxygen | 3 |
| 28 |
and is consequently a teroxide. Muriate of gold consists of
| 2 atoms muriatic acid | 9.25 |
| 1 " per oxide of gold | 28. |
| 5 " water | 5.625 |
| 42.875 |
Edin. Journal, p. 182.