Page:Treatise on poisons in relation to medical jurisprudence, physiology, and the practice of physic (IA treatiseonpoison00chriuoft).pdf/432

 last experimentalists differ from Orfila in assigning to sugar of lead a property like that possessed by arsenic, of acting on the alimentary canal, even when applied to a wound, or directly introduced into the blood. For Campbell found the stomach corrugated and red, and the small intestines also vascular; while Gaspard not only observed analogous appearances after death, but even also witnessed all the symptoms of violent dysentery during life. In farther proof of the local irritating power of this poison, it may be added, that when sugar of lead was injected into the rectum Campbell found it to cause purging, tenesmus, itching of the anus, and great debility.

I have found that the nitrate of lead is powerfully irritant and corrosive in the dose of 400 grains. This quantity dissolved in four ounces of water killed a strong dog in sixteen hours, producing violent efforts to vomit and diarrhœa. And after death the whole inner membrane of the gullet and stomach, and the villi of the upper half of the small intestines, were uniformly white, brittle, and evidently disintegrated; and the mucous coat of the great intestines was bright red in parallel lines.

The only inquiries I have hitherto met with, which assign to lead in continued small doses the power of producing in animals the peculiar colic and palsy often produced by it in man are those of Schloepfer, related in his thesis on the effects of poisons when injected into the windpipe. He found that the acetate, introduced through this channel in successive doses of ten grains, brought on all the symptoms of colica pictonum, preceded by oppressed breathing, and ending fatally with palsy and convulsions in the course of three weeks. More recently Dr. Wibmer, in the course of some experiments on the long-continued use of acetate and carbonate of lead, remarked weakness and stiffness of the limbs in dogs; and in the rabbit I have observed in the like circumstances gradually increasing weakness, ending in complete palsy of the fore legs.

The compounds of lead seem to produce their effects on the animal body through the medium of absorption. At all events they are absorbed in the course of their action, and are diffused throughout the animal textures. Lead was long sought for with variable and dubious success in the fluids and solids of men and animals killed by it or labouring under its effects. But the late improvements in physiological science and chemical analysis have demonstrated, that it may always be detected in favourable circumstances in the liver and kidneys, often in the spleen and in the urine, and sometimes even in the muscles. Wibmer was the first who satisfactorily proved its presence. In dogs poisoned slowly by the acetate or carbonate of lead in frequent small doses, and dying with symptoms of lead-colic and palsy, he found the metal distinctly in the liver, muscles, and spinal cord, and more obscurely in the blood, by drying and deflagrating the animal matter with nitre, acting on the residue with nitric acid, neutralizing the solution, and testing it with hydrosul-*