While this metal, when pure, is not itself poisonous, its compounds are; and they are produced by the action on copper of the fluids of the stomach, or by acids and other materials used in cooking, pickling, etc. In this way copper poisoning sometimes occurs, as well as among those working in copper. Mineral water (carbonic acid water, soda-water) dissolves cop-per ; hence reservoirs of that metal, without any, or with only an imperfect, lining of something not soluble, ought not to be used for it. The compounds of copper most often acting poisonously are, blue vitriol (bluestone), the sulphate; and verdigris, the subacetate of copper. In large amount taken at once, either of these will cause severe vomiting, pain in the abdomen, and purging; afterwards headache, and, in fatal cases, convulsions or paralysis before death. Slow poisoning will result from taking small amounts of copper daily, as in cooked or pickled articles, for a length of time. Symptoms of this are, a coppery taste in the mouth, with parched tongue and throat; nausea, retching, perhaps vomiting; pains in the stomach and bowels ; diarrhoea, with straining ; weakness, with nervous restlessness ; dizziness, cold sweats, cramps, and at last convulsions.

Treatment for rapid copper poisoning (as it is itself an emetic) should consist in giving an abundance of whites of eggs ; albumen making a harmless compound with copper. Milk may be given freely if no eggs are at hand ; its effect is of the same kind. For slow copper poisoning, the main thing is to withdraw the cause, in whatever thing or things it may exist. Then, a milk diet, with moderate doses of an opiate, as paregoric, or small doses of laudanum, to assuage the pain and diarrhoea, will be suitable.