84 WRITINGS OF JAMES SMITHSON. 



ON QUADRUPLE AND BINARY COMPOUNDS, 

 PARTICULARLY SULPIIURETS. 



From the Philosophical Magazine, London, Vol. XXIX, 1807, p. 275. 

 Kead December 24, 1807. 



A paper, by Mr. Smithson, on quadruple and binary com- 

 pounds, particularly the sulphurets, was read. The author 

 seemed to doubt the propriety of the distinction, or rather 

 the existence, of quadruple compounds, believed that only 

 two substances could enter as elements in the composition 

 of one body, and contended that in cases of quadruple com- 

 pounds, a new and very diiFerent substance was formed, 

 which had very little relation to the radical or elementary 

 principles of which it was believed to be composed. This 

 opinion he supported by reference to the sulphurets of lead 

 (galena) and of antimony, and to the facts developed by 

 crystallography. In the latter science he took occasion to 

 correct and confirm some remarks of his in the Transac- 

 tions for 1804, on different crystals, which he acknowledged 

 have not hitherto been found in nature. 



ON THE COMPOSITION OF THE COMPOUND SUL- 

 PIIURET FROM IIUEL BOYS, AND AN AC- 

 COUNT OF ITS CRYSTALS. 



Prom the Philosophical Transactions of the Royal Society of London, 

 Vol. XCVIII, Part I, 1808, p. 65.— Kead January 28, 1808. 



It is but very lately that I have seen the Philosophical 

 Transactions for 1804, and become acquainted with the two 

 pupers on the compound sulphuret of lead, antimony, and 

 copper contained in the first part of it, which circumstance 



