Separation of arsenic : From the Transactions of the Society of Arts. Vol. LI. The large gold medal was presented to Mr. James Marsh, of the Royal Arsenal, Woolwich, for his method of separating small quantities of arsenic from substances with which it may have been mixed. / [By James Marsh].

  • Marsh, James.
Date:
1842
Catalogue details

Licence: Public Domain Mark

Credit: Separation of arsenic : From the Transactions of the Society of Arts. Vol. LI. The large gold medal was presented to Mr. James Marsh, of the Royal Arsenal, Woolwich, for his method of separating small quantities of arsenic from substances with which it may have been mixed. / [By James Marsh]. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

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    SEPARATION OF ARSENIC. FROM THE TRANSACTIONS OF THE SOCIETY OF ARTS. VOL. LI. The Large Gold Medal was presented to Mr. James Marsh, of the Royal Arsenal, Woolwich, for his Method of separating Small Quantities of Arsenic from Substances with which it may have been mixed. Notwithstanding the improved methods that have of late been invented of detecting the presence of small quantites of arsenic in the food, in the contents of the stomach, and mixed with various other animal and vege- table matters, a process was still wanting for separating it expeditiously and commodiously, and presenting it in a pure unequivocal form for examination by the appropriate tests. Such a process should be capable of detecting- arsenic not only in its usual state of white arsenic or arsenious acid, but likewise in that of arsenic acid and of all the compound salts formed by the union of either of these acids with alkaline substances. It ought, also, to ex- hibit the arsenic in its reguline or metallic state, free from the ambiguity which is sometimes caused by the use of carbonaceous reducing fluxes. It appeared to me, that these objects might be attained by presenting to the arsenic hydrogen gas in its nascent state : the first action of which would be to deoxygenate the arsenic; and the next, to combine with the arsenic, thus deoxygenated, into