_Chemical Tests._—It has a grayish, greenish, or yellowish colour when solid; its dust smells of sulphuretted hydrogen, which is also copiously disengaged from it by the mineral acids: and it forms with water a yellow solution of the same odour.—In composite fluids it may be detected by heating it with acetic acid, and passing the disengaged gases through solution of acetate of lead, in which a black precipitate of sulphuret of lead is produced, from the action of sulphuretted-hydrogen.[481] _Action and Symptoms._—Orfila found that a solution of six drachms and a half, secured in the stomach of a dog by a ligature on the gullet, caused death by tetanus in seven minutes, without leaving any morbid appearance in the body; that inferior doses caused death in the same manner, but at a later period, and with symptoms of irritation in the alimentary canal, which also was seen red, black, or even ulcerated after death; that a solution of twenty-two grains injected into the jugular vein killed a dog in two minutes, convulsions having preceded death, and the heart being found paralysed immediately after it; and that a drachm and a half thrust in small fragments under the skin occasioned death in thirteen hours with coma and extensive inflammation of the cellular tissue.[482] There can be no doubt, therefore, that liver of sulphur is a true narcotic acrid poison.—It is absorbed, and may be detected in the blood, liver, kidneys, and urine by Orfila’s process.[483] Orfila has collected three cases of poisoning in the human subject with this substance;[484] and a fourth has been related by M. Cayol.[485] Of these cases two proved fatal in less than fifteen minutes; and the symptoms were acrid taste, slight vomiting, mortal faintness, and convulsions, with an important chemical sign, the tainting of the air with the odour of sulphuretted-hydrogen. The dose in one case was about three drachms. The two other patients, who recovered, were for some days dangerously ill. The symptoms were burning pain and constriction in the throat, gullet, and stomach; frequent vomiting, at first sulphureous, afterwards sanguinolent; purging, at first sulphureous; sulphureous exhalations from the mouth; pulse at first quick and strong, afterwards feeble, fluttering, and almost imperceptible; in one case sopor; finally severe inflammation of the gullet, stomach and intestines, which abated in three days. One of these patients took four drachms of sulphuret of soda, the other two ounces of sulphuret of potass; but it is probable, that the latter dose was partly decomposed by long keeping. _Morbid Appearances._—The morbid appearances in the two fatal cases were great lividity of the face and extremities, and exhaustion of muscular contractility immediately after death; the stomach was red internally, and lined with sulphur; the duodenum also red; the lungs soft, gorged with black fluid blood, and not crepitant.