ARSENIATS. 
When heated along with charcoal powder, they are 
decomposed, and arsenic sublimes. 
Sp. 1. Arsemat of Barytes. 
THIS salt was formed by Scheele by dissolving bary 
tes in arsenic acid. When the saturation was nearly 
completed, the salt precipitated in the state of an inso 
luble powder. It may be formed also by mixing arse 
niat of potass with nitrat or muriat of barytes. This 
salt is insoluble in water except there be an excess of 
acid. When exposed to a violent heat, it shows a ten 
dency to melt, but is not decomposed*. 
Sp. 2. Arseniat of Strontian. 
Unknown. 
Sp. 3. Arseniat of Lime. 
WHEN arsenic acid is dropt into lime-water, arseniat 
of lime is precipitated; but if an excess of acid be add 
ed, the salt is redissolved, and yields when evaporated 
small crystals of arseniat of lime, which are soluble in 
water, and decomposed by sulphuric acid. This salt may 
be formed also by dissolving chalk in arsenic acid, or 
by mixing the alkaline arseniats with the the nitrat, 
muriat or acetite of lime. Arseniat of lime, when 
heated, exhibits the same phenomena as the first spe 
cies f. 
Sp. 4. Arseniat of Magnesia. 
MAGNESIA dissolves in arsenic acid ; but when the 
acid is nearly saturated, the solution becomés thick and 
Ibid. p. 157. 
& Scheele, i. 163. 
Bb4 
591 
Chap. III. 
Character.