Licence: Public Domain Mark
Credit: Medical jurisprudence / by Alfred Swaine Taylor. Source: Wellcome Collection.
Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.
942/968 (page 928)
![(June and July 1859) to try the effects of distillation for the separation of arsenic from antimony, mercury, bismuth, and iron. The results were on the wliole satisfactory. In some of the experiments it was found that more than one distillation was necessary for the purpose of a complete separation of the arsenic. On further trials I found that arsenic, whether in the absorbed or in the free state, was thus completely -separated from dried organic matter. The ciiloride of arsenic pro- duced in this process has been long known as a volatile com- pound. In 1841 it was obtained by Dupas(|uier in distilling a solution of arsenious acid in hydrochloric acid. (Pereira. Ele- ments of Materia Medica, vol. 1 p. 720.) Pereira repealed tliese experiments and obtained the liquid called by Dupasquier the terchloride of arsenic. In 1816-7 I found, in using Reinsch's process in numerous medico-legal analyses, that there was occasionally a great loss of arsenic; and in May 18-»7 I satisfied myself by direct experiment that a quantity of arsenic was uniformly distilled over with the hydrochloric acid. The only use which I then made of the volatile product thus ob- tained, was to apply to it as well as to the residue in the retort, the process of Ueinsch. These experiments were published in detail in the first edition of my work on Poiscss i November 1847), p. :U>:i. In 1849 my friend and colleague, the late Mr. Arthur Aikin, in his lectures at tJuy's Hospital. denioubtraieJ the method of procuring chloride or butter of arsenic by dis- tilling a mixture of salt and sulphuric acid with arsenious acid. AVith the exception ot' the ex|)eriments made by my- self in 184G-7, these well known facts were not applied to the purposes of toxicological research. Dr. Schneider of N'ienna w;is the first to employ them in a practical form for the .separation of absorbed or free arsenic Ironi organic matter. In 18) 1-2 he published an account of his method, which consisted in mixing an excess of common salt with the organic substance, and then distilling the mixture with strong sulphuric acid. This wa.s the chemical process which had been ])ursued by ^Slr. .\ikin two years i)reviously for the pur- pose of procuring chloride of arsenic. This jirocess, which was adopted by Otto and other (ierman cheiuists. is well known on the continent, and has been noticed in most works ou toxicology under the name of Srliniulir'.'i iiroce.<s. Dr. Schneider has published the most complete account of it in his Oerichtli-he Cliemie. W ien, I8j2, j). 20(!. with an illustration of the apparatus which he used. A description of .Schneider's pro- cess was also |iubli>hed in the Pharmacevitioal .louriial tor July I8.>.'!, p. .'18. It appears to have found but little lavour in this country. The only chemist who, so tar as I know, employed it lor medico-legal pur|ioses. was Dr. Clark of ,\berdeen. In the liltli edition of my Medical Jurisprudence, published in 1854,](https://iiif.wellcomecollection.org/image/b21935221_0942.jp2/full/800%2C/0/default.jpg)
