Intelligence and Miscellaneous Articles. ,237 



a notaWe quantity of the metallic oxide. If a solution of muriate 

 of ammonia is boiled with sulphate of lead, and the liquor be filtered 

 while boiling, crystals of chloride of lead are formed, and the solu- 

 tion contains sulphate of ammonia: when the sulphate is repeatedly 

 boiled in fresh portions of solution of muriate of ammonia, the sul- 

 phate of lead is eventually perfectly decomposed. Sulphate of lead 

 is slightly soluble in water, for sulphuretted hydrogen and nitrate 

 of barytes both occasion precipitation in it.— Journal de Pharmacie, 

 September 1834. 



PEROXIDE OF IRON AS AN ANTIDOTE TO ARSENIOUS ACID, 



The following letter, addressed by Dr. Bunson to M. Poggen- 

 dorft', is translated from the Journal de Pharmacie for October 

 last. 



Gottingen, May 1, 1834. 



It is long since I observed, that a solution of arsenious acid is 

 so completely precipitated by pure hydrate of iron recently preci- 

 pitated, and suspended in water, that a current of sulphuretted hy- 

 drogen gas passed into the liquor after filtration, and the addition 

 of a small quantity of muriatic acid, does not indicate the presence 

 of the smallest portion of arsenious acid. 



1 have also found, that if a few drops of ammonia be added to 

 this substance, and it be digested in a gentle heat, with arsenious 

 acid reduced to fine powder, a subperarsenite of iron, which is per- 

 fectly insoluble, is quickly formed. A series of experiments, foun- 

 ded upon this observation, has firmly persuaded me that this sub- 

 stance combines the most favourable properties for serving as an 

 antidote to arsenious acid, both solid and in solution. Dr. Berthold 

 consented, at my request, to assist me in examining this subject in 

 all its bearings, and to submit it to the most rigorous experiments. 

 The results of this examination have much exceeded our expecta- 

 tion, and have confirmed us in the persuasion that perhydrate of 

 iron is a better antidote for arsenious acid, both solid and in solu- 

 tion, than albumen is for corrosive sublimate. 



Two young dogs, scarcely 12 inches high, had four to eight grains 

 of arsenious acid given to them in fine powder, and the oesophagus was 

 tied to prevent vomiting ; they lived more than a week without ex- 

 hibiting the slightest symptoms of poisoning by arsenic, either du- 

 ring lite or on examination after death. The excrements voided were 

 in very small quantity, for the animals were deprived of food and 

 drink, and they contained almost the whole of the poisonous sub- 

 stance in the state of subperarsenite of iron. 



We satisfied ourselves, by experiments upon animals, that a quan- 

 tity of perhydrate of iron, equal to four or six drams of the peroxide 

 of this metal, with sixteen drops of ammonia, is sufficient to trans- 

 form in the stomach eight or ten grains of well-pulverized arsenious 

 acid into insoluble arsenite. It is besides easy to see, that in cases 

 of poisoning by arsenic, this substance, with or without ammonia, 

 may be exhibited in much larger quantity, either by the mouth or 

 as an enema ; for the perhydrate of iron being a body totally inso- 



