Is a mixed solution of arsenite and carbonate of potassium flavoured with compound tincture of lavender. Contains 1 part arsenious acid in 100 of water, or about 4 1/2 grains in 1 fl. oz., B. and U.S.P. In the B.P. 1867, it contained 4 grs. in 1 fl. oz., or 1 in 109

Characters. - A reddish liquid, alkaline to test-paper, and having the odour of lavender.

Reaction. - After being acidulated with hydrochloric acid, it gives, with sulphuretted hydrogen, a yellow precipitate, which is brightest when the arsenical solution has been previously diluted.

Dose. - 2 to 8 minims.

Use. - This is the preparation of arsenic most commonly employed. It may be given along with alkalis.

Liquor Arsenici Hydrochloricus, B.P.; Liquor Acidi Arseniosi, U.S.P. Hydrochloric Solution of Arsenic, B.P.; Solution of Arsenious Acid, U.S.P. - A solution of arsenious acid, 87 grs. with 2 fl. dr. of hydrochloric acid in 20 fl. oz. of water, B.P.; 1 part arsenious acid and 2 of hydrochloric in 100 of water, U.S.P. It is a 1 per cent. solution in both Pharmacopoeias.

Characters and Reaction. - A colourless liquid, having an acid reaction. Sulphuretted hydrogen gives at once a bright yellow precipitate.

Dose. - 2 to 8 minims.

Use. - Some think it milder than the ordinary liquor. Garrod thinks not. It can be given along with per chloride of iron in solution, or with acids.