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XLVIII. On a new Oxide of Sulphur and an analogous Selenium 

 Substitution Product of the same. By Rudolph Weber*. 



IT is known that deeply coloured products are obtained by 

 the action of sulphur, selenium, and tellurium upon sul- 

 phuric anhydride or upon fuming oil of vitriol. 



In his research on tellurium M. von Reichenstein made the 

 ol >scTvation that that element dissolves in cold oil of vitriol, 

 and colours the liquid amethyst, and that on the addition of 

 water the tellurium is precipitated in the metallic state. 

 Bucholz obtained a deep-blue-coloured substance by distilla- 

 tion of fuming sulphuric acid with sulphur ; at a later time 

 the same compound was obtained by Vogel by the direct 

 action of sulphur upon sulphuric acid containing sulphuric 

 anhydride. 



Magnus observed that selenium dissolved in oil of vitriol 

 with the production of an intensely green-coloured liquid, 

 but was again precipitated, for the most part, on the addition 

 of water. 



The observations hitherto made do not allow of any conclu- 

 sions being drawn as to the chemical nature of these coloured sub- 

 stances. Not only does the composition of these bodies remain 

 undecided by the recorded observations, but the very existence 

 of chemical compounds of sulphur, selenium, and tellurium 

 with the constituents of sulphuric acid must yet be regarded 

 as doubtful. The view that the coloured bodies are mere 

 solutions of the elements in acid derives support from the 

 circumstance that the coloured liquids are decomposed by 

 water with deposition of the elementary bodies. In the pro- 

 secution of a research upon sulphuric anhydride (the general 

 results of which will be communicated hereafter), I have been 

 led to study the action of sulphur and of selenium upon this 

 compound ; and I have obtained bodies of definite chemical 

 composition which dissolve in strong oil of vitriol, as also in 

 sulphuric anhydride (prepared in the ordinary way), to form 

 coloured liquids which agree in all essential particulars with 

 the substances obtained by the above-mentioned chemists. 

 The substances prepared by me are, a new oxide of sulphur, and 

 a selenium substitution product of this oxide. 



Before stating the results of my investigation it may be 

 well to give a slight historical sketch of the facts which are 

 known concerning the blue sulphur compound. 



Bucholz t, in 1804, obtained a blue distillate by heating a 

 mixture of sulphur and oil of vitriol in a retort. He did not 



* From Pogg. Ann., vol. clvi. p. 531. Translated by M. M. Pattison 

 Muir, Tli© Owens College, Manchester, 

 t Gehlen's Neues J. der Chemie, vol. iii. p. 7. 



