Oxalic acid is one of the poisons alluded to under the head of General Poisoning,—of whose operation distinct evidence may sometimes (though certainly not always) be found in the symptoms. If a person, immediately after swallowing a solution of a crystalline salt, which tasted purely and strongly acid, is attacked with burning in the throat, then with burning in the stomach, vomiting particularly of bloody matter, imperceptible pulse and excessive languor, and dies in half an hour, or still more in twenty, fifteen, or ten minutes, I do not know any fallacy which can interfere with the conclusion, that oxalic acid was the cause of death. No parallel disease begins so abruptly and terminates so soon; and no other crystalline poison has the same effects.
Poisoning with the Oxalates.—Oxalic acid is one of the best examples of a poison that acts through all its soluble chemical combinations. Dr. Coindet and I found that the oxalates of potash and ammonia are little inferior in energy to the acid. They do not corrode, indeed, and scarcely ever irritate; but they produce tetanus and coma, like the diluted acid. Half a drachm of oxalic acid neutralized with potass will kill a rabbit in seventeen minutes; ninety grains of neutral oxalate of ammonia will kill a strong cat in nine minutes.[1] The binoxalate of potash, the most familiar of the salts of oxalic acid, was not tried by us. But the preceding facts would leave little doubt of its being a poison.
Since the last edition of this work was published several cases have occurred which amply confirm the results of experimental inquiry. In Dr. Babington's case alluded to above, the greater part of the oxalic acid had been neutralized by bicarbonnte of soda [p. 176].—Mr. Tripier has communicated the particulars of a case in which half an ounce of the binoxalate of potash was taken by mistake for bitartrate of potash in hot water, and caused death in eight minutes, after an attack of violent pain and convulsions.[2]—A young woman at Bordeaux was attacked with frequent vomiting after a dose of a drachm and a half of the same salt dissolved in a ptisane. Next morning a similar dose caused bloody vomiting and acute pain at the pit of the stomach; and a third dose the following day excited delirium, more violent vomiting, and death in the course of an hour.[3]—A girl in London swallowed about an ounce of the same salt dissolved in hot water. Sickness and faintness ensued, with imperceptible pulse, cold, clammy skin, rigors, scalding of the mouth and throat, pain in the back, soreness of the eyes, redness of the conjunctivæ, and dilatation of the pupils. Afterwards there was reaction, with a full frequent pulse, hot skin, flushed countenance, headache, thirst, and tenderness of the abdomen. She recovered under the use of chalk, external heat, ether and opium draughts, leeches and sinapisms to the belly, and carbonate of ammonia.[4]
