Observations on Reinsch's test for arsenic / by William Odling.

  • Odling, William, 1829-1921.
Date:
1800-1899
Catalogue details

Licence: Public Domain Mark

Credit: Observations on Reinsch's test for arsenic / by William Odling. 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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    OBSERVATIONS ^ Of % t Nil ! Or « REINSCIPS TEST FOR ARSENIC. By WILLIAM ODLING, M.B., F.C.S. e- I believe that all British toxicologists are fully agreed upon the merits of ReinsclRs process for the detection of arsenic. Its delicacy, its freedom from fallacy, the facility and rapidity of its application, and the non-requirement of any special form of apparatus, are advantages sufficiently obvious. The tedious and complicated processes, with their elaborate forms of apparatus, which are from time to time described in foreign periodicals, are rather interesting as specimens of perverted ingenuity, than useful as improved means for the detection of the poison. If, in the performance of Reinsctds test, the grey metallic deposit upon copper yields a crystalline sublimate which, when treated with nitric and hydrochloric acids and evaporated to dryness, leaves a residue giving a brick-dust coloured precipitate with nitrate of silver, its arsenical nature is indubitable,—there is no fallacy whatever. Should the deposit be not possessed of these characters, the suspected substance must be further ex- amined for the presence of antimony, bismuth, sulphur, &c. But supposing that we are unable to obtain any characteristic deposit upon the copper, are we justified in affirming the ab- sence of arsenic in the substance under examination ? Is it not possible that our want of success may be due to the insuffi- cient delicacy of the process, or to some unavoidable loss in its performance, or to the existence of the arsenic in some par- ticular form of combination not amenable to the action of the test ? I propose to consider these three points seriatim. Delicacy of Reinsch’s process.—-Dr. Taylor has very clearly pointed out, that in considering the delicacy of any test, we ix. 19