94 
Extracts from British and Foreign Journals. 
facts and fallacies connected with the research 
FOR ARSENIC AND ANTIMONY; WITH SUGGESTIONS FOR 
A METHOD OF SEPARATING THESE POISONS FROM 
ORGANIC MATTER. 
By Alfred S. Taylor, M.D., F.R.S. 
[Continuedfrom p. 41 .) 
Reinsch' s Process. 
Hugo Reinsch first announced his discovery in 1841.* He 
accidentally observed that a piece of copper which he had 
immersed in commercial hydrochloric acid acquired, after a 
time, a dark-gray metallic deposit, resembling iron. This 
proved, on examination, to be a deposit of metallic arsenic 
derived from an impure sample of hydrochloric acid. The 
acid was found to contain one grain of arsenious acid in 500 
grains. This deposition of arsenic was observed to take place 
on copper whether the acid was hot or cold, and whether it 
was concentrated or diluted, but in all cases heat was found 
to accelerate it considerably. Reinsch further ascertained 
that copper might be boiled in a solution of arsenious acid, or 
in pure hydrochloric acid, without any similar deposit being 
formed. Provided there is not too free an access of air, and 
the metallic copper is wholly immersed in the acid, the metal 
will remain unchanged for a much longer period in the con¬ 
centrated than in the diluted acid. If there is a free expo¬ 
sure to air, the metal is rapidly dissolved (as subchloride) 
by the concentrated acid, but not by the diluted acid. 
The proportion of acid to water which was • found most 
convenient for the deposition of arsenic is not stated by 
Reinsch. One part of acid by measure to six, eight, or ten 
of water, have been the proportions generally adopted by 
analysts. From his experiments Reinsch drew the conclusion 
that the arsenic was so completely removed by copper on 
boiling it in the acid, that the residuary liquid gave no trace 
of the poison on the subsequent use of Marsh's apparatus. 
* Erdmann’s ‘Journal fur Praktische Chemie/ No. 19, 1841. ‘Philo¬ 
sophical Magazine/ No. 126, Dec., 1841. ‘Annales d’Hygiene et de 
Medecine Legale/ 1843, t. i, p. 439. See also a paper by the writer in the 
‘British and Foreign Medical Review’ for July, 1843, p. 281. 
