696 iJEPORT— 1900. 



author cdttiet discuss here ; he contents himself with stating that after some yeal-S 

 of experience he has iifever learnt of the occurrence of any case of plumhism where 

 the acidity of the water has been under the equivalent of 0'5 part of sulphuric acid 

 per lOO-OOO of water, and this he tentatively proposes as a limiting standard of 

 acidity for potable waters of moorland origin when the acidity is determined 

 iu the manner already described with phenolphthalein as indicator. 



The average acidity of nine samples of water not above suspicion in this 

 respect was OfiJ, ranging from 0-53 to 0-91 ; while on the other hand sixty-one 

 samples above reproach from neighbourhoods where plumbism has not been known 

 had an average acidity of 027, the extremes being 0'20 and 0'41. 



5. On the Effects of Copper on the Human Body. 

 By ThoiMAs Whiteside Hime, B.A., M.D. 



The recrudescence of an agitation by some public analysts as to alleged 

 danger to health produced by copper has rendered it desirable to make an investi- 

 gation into the subject, although it was long since satisfactorily disposed of, from 

 a point of view hitherto scarcely utilised as it deserves, and at the same time to 

 review the general results attained. The examination of the two principal 

 excretions, solid and liquid, by which copper is eliminated from the body, offered a 

 promising means of judging of the effects of the agent, whether merely' swallowed 

 or also absorbed. These excretions have therefore been examined during a period 

 of several months, from a number of healthy persons engaged, some for many years, 

 in dealing with copper, either in smelting works or as workers in its alloys, brass, 

 &c., or from healthy persons unconnected with any kind of copper work, who had 

 intentionally swallowed some compound of copper in improperly so-called 

 ' greened ' vegetables (they are not rendered ' green ' by treatment with copper) or 

 otherwise. Copper was found in relative nbundance in the excretions of all of 

 these persons, yet they had enjoyed perfect health, and were unconscious of any- 

 thing abnormal existing in their excretions. It is excreted slowly, and some 

 weeks may elapse before the whole of the copper-compound ingested is got rid of. 

 That fact, that copper may, after being swallowed, be absorbed into the blood and 

 exist there for months, and no doubt during at least twenty years, without indicat- 

 ing its presence by the slightest interference with health, or indeed in any way 

 whatever, has thus been established beyond question. In one case, a braes-finisher 

 aged thirty-eight, who had been thirty years engaged in brass-work, copper was 

 found on various occasions when sought, during several months. For the last 

 fourteen years this man has never drawn any money from his sick club, and he 

 has had perfect health. The copper exists in the excretions, as it dees in coppered 

 vegetables, not as copper, but as an insoluble compound, which when tested 

 directly for copper gives no indication of copper being present in any form. As a 

 fact, no copper is present. It is entirely unjustifiable to speak of copper being a 

 poison because when combined with some other elements poisonous efl'ects may be 

 produced by the compound. Because copper and arsenic combined, forming copper 

 arsenite, which is not copper, is poisonous, a death due to copper arsenite is 

 reported and quoted for sixty years in all the text-books as due to ' poisoning by 

 copper ! ' As well call iron a poison, because it too, when combined to form a new- 

 compound, arseniate of iron, may prove poisonous. Copper exists in a great number 

 of plants, including cereals, mineral waters, wines, shell-fish, fruits, and various kinds 

 of animal flesh. It has been calculated that a man eating good bread, ' coppered ' 

 only by nature, would consume in this way alone some 93 grains of copper, 

 corresponding to 366 grains of the sulphate. Thousands of wealthy and educated 

 persons who flock yearly to the health-restoring springs of Wiesbaden, Teplitz, 

 Pyrmont, &c., consume copper in every glass of water they drink, yet their health 

 improves, they return yearly to derive fresh benefit, and are unaware that they are 

 being ' poisoned.' Many trustworthy observers have found copper as a normal 

 constituent in the human body. That the consumption of vegetables which have 

 been treated with copper to preserve their natural green is perfectly harmless has 



