James Smithson 13 



minerals in the rank of true carbonates, while his remarks on 

 the action of the ores of zinc before the blowpipe evince much 

 discernment ; and the paper, on the whole, is altogether a 

 creditable one. 1 



At this period he seems to have ceased his contributions 

 to the Royal Society, and later we find his name more 

 frequently in the "Annals of Philosophy," a journal of high 

 character, where there is a communication from him dated 

 Paris, May 22, 1819, on " Plombe gomme," and about the 

 same time a paper on a native sulphuret of lead and arsenic, 

 with numerous other papers, among which is one in 1822, 

 "On the Detection of Very Minute Quantities of Arsenic and 

 Mercury," where he contributed a method which was gener- 

 ally used by chemists until quite modern tests superseded it. 

 The papers 2 in all number twenty-seven, of which eight 

 here cited were published in the " Philosophical Transac- 

 tions of the Royal Society," between the years 1791 and 1807, 

 one in the "Philosophical Magazine" in 1807, and eighteen 

 in "Thomson's Annals of Philosophy," between 1819 and 1825, 

 and these all give the idea of an assiduous and faithful 

 experimenter, an impression enlarged by the last one of 

 the series, bearing date of June, 1824, which contains some 

 observations on the formation of the Kirkdale Cave, forcibly 



1 Smithson's subsequent communications " On a Saline Substance from Mount Ve- 

 to the Philosophical Transactions are six in suvius," 1813. (Volume cm, page 256.) 

 number : " A few Facts relative to the Coloring Mat- 



"An Account of a Discovery of Native ter of Some Vegetables," 1817. (Volume 



Minium," submitted in a letter dated from cvm, page no.) 



Cassel, in Hesse, March 2, 1806. (Volume A paper by him " On Quadruple and Bi- 



xcvi, part I, page 267.) nary Compounds, particularly Sulphurets," 



" On the Composition of the Compound was also published in the " Philosophical 



Sulphuret from Huel Boys, and an Account Magazine," 1807. (Volume xxix, page 275.) 



of its Crystals," 1808. (Volume xcvm, page 2 These papers were collected and edited 



55.) by William J. Rhees, and are contained in 



"On the Composition of Zeolite," 1811. Volume xxi of the "Smithsonian Miscella- 



(Volume ci, page 171.) neous Collections," under the title of "The 



"On a Substance from the Elm Tree, called Scientific Writings of James Smithson" 



Ulmin," 1813. (Volume cm, page 64.) (1879). 



