Acetic Acid
The solution obtained by treating the alimentary canal with water is distilled, as in testing for nitric and hydrochloric acids, and the following properties verified in the distillate: 1st. It has an acid reaction, and possesses the odor of vinegar; 2nd, unless previously neutralized with a base, it fails to redden the per-salts of iron; 3rd, if the distillate is added to a solution of the per-salts mentioned and sulphuretted hydrogen conducted through the fluid, a black precipitate is formed; 4th, upon boiling the still acid fluid with a small quantity of starch, the property of the latter to become colored in presence of free iodine is not changed; 5th, if heated with an excess of litharge, a basic salt which restores the blue color to reddened litmus paper is produced.