The evil results of this chloral-drinking are especially to be looked for in the mental faculties, and the alienists have had since 1869 a new insanity-producing factor. In the asylums may usually be found several cases of melancholia and mania referred rightly (or wrongly) to chloral-drinking. Symptoms other than cerebral are chilliness of the body, inclination to fainting, clonic convulsions, and a want of co-ordination of the muscles of the lower extremities. In a case recorded by Husband,[189] a lady, after twelve days’ treatment by chloral hydrate, in doses of from 1 to 2 grms. (15·4 to 30·8 grains), suffered from a scarlatina-like rash, which was followed by desquamation. Among the insane, it has also been noticed that its use has been followed by nettle-rash and petechiæ (Reimer and others). [189] _Lancet_, 1871. § 206. =Excretion of Chloral.=--Chloral hydrate is separated in the urine partly as urochloral acid (C₈H₁₁Cl₃O₇). Butylchloral is separated as butyl urochloral acid (C₁₀H₁₅Cl₂O₇). Urochloral acid is crystalline, soluble in water, in alcohol, and in ether, reduces copper from Fehling’s solution, and rotates a ray of polarised light to the left. Urochloral acid, on boiling with either dilute sulphuric or hydrochloric acid, splits up into trichlorethyl alcohol and glycuronic acid-- C₈H₁₁Cl₃O₇ + H₂O = C₂H₃Cl₃O + C₆H₁₀O₇. Trichloralcohol is an oily fluid (boiling-point 150°-152°); it yields by oxidation trichloracetic acid. Urobutyl chloral acid gives on treatment with mineral acids trichlorbutyl alcohol and glycuronic acid. To separate urochloral acid from the urine the following process has been found successful:-- The urine is evaporated to a syrup at the heat of the water-bath, and then strongly acidulated with sulphuric acid and repeatedly shaken out in a separating tube with a mixture of 3 vols. of ether and 1 vol. of alcohol. The ether-alcohol is separated and distilled off, the acid residue is neutralised with KHO, or potassic carbonate, and evaporated; the dry mass is then taken up with 90 per cent. alcohol, the filtrate precipitated with ether, and the precipitate washed with ether and absolute alcohol. Next the precipitate is boiled with absolute alcohol and filtered hot. On cooling, the potassium salt of urochloral acid separates out in tufts of silky needles. The crystals are dried over sulphuric acid and again washed several times with absolute alcohol and ether to remove impurities.