Synonym. - Liquor Potasssae Arscnitis. Fowler's Solution of Arsenic. Take of
Arsenious Acid, in powder. Carbonate of Potash . .
of each .
Rectified Spirit ....
5 fluid drachms;
Distilled Water ....
Place the Arsenious Acid and the Carbonate of Potash in a flask with 10 ounces of the water, and apply heat until a clear solution is obtained. Allow this to cool, then add the rectified spirit, and as much distilled water as will make the bulk 1 pint.
Characters and Tests. - A colourless liquid, alkaline to test-paper. 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. 441.5 grains by weight (1 fluid ounce) boiled for five minutes with 10 grains of Bi-carbonate of Soda, and when cold diluted with 6 fluid ounces of water to which a little mucilage of Starch has Been added, does not give with the volumetric solution of Iodine a permanent blue colour until 808 grain measures have been added; corresponding to 4 grains of Arsenious Acid in 1 fluid ounce.
Preparation. - As this solution contains 1 grain in 120 minims, 1 fluid drachm mixed with 7 fluid drachms of proof spirit forms the 3x attenuation, after which rectified spirit can be used.