fi Kr. hatchett on magnetical pyrites. 



II. 



An Analyfis of the Magnetical Pj/rites; uith Benmrks on fame of 

 t/ie other Sulphurets of Iron, % Charles Hatchett, 

 Efq. F. R. S, From the FhilofophicaL Tran/aci ions for \m^. 



(Concluded from page 276.) 



§ VII. 



Whether the OO far, therefore, as can be proved by fimilarity in chemical 

 whh^mlmmum Properties and analyfis, the magnetical pyrites is indifputabiy 

 offulphurbe, a natural fulphuret, completely the fame with ihat wliich till 

 ^'^^iKtlc^^^"'^'*^' now has been only known as an artificial produfl j but, that 

 the mind may be perfeflly fatisfied, another quefiion nuift be 

 folved, namely, how far do they accord in receiving and re- 

 taining the property of magnelifnrt ? common pyrites do not 

 appear to afFe6t the magnetic needle, or, if fomeof them fiightly 

 J16I by attradlion, (which however I never could perceive, nor 

 recoiled to have read in works exprefsly relating to magnetifm J 

 yet they do not poffefs, nor appear capable of acquiring, any 

 magnetic polarity. As, therefore, the iron of pyrites is uii^ 

 doubtedly in the metallic flale, and in a confiderable proportion, 

 the defiru6lion of this chara6terifiic property of metallic iron, 

 ^luft be afcribed to the other ingredient, fulphur. 

 The artl.^cJal But we have lately feen, that a natural combination of iron 



compound is not ^^^ ^6,50 or 37 per cent, of fulphur, is in pofTeffiou of all the 

 4 piere nfii^ture. , r ,,., . ,. ' , , , 



properties luppoled hithertoto appertain (many marked degree) 



almofl exclufively to the well known magnetic iron ore; and 



that the combination alluded to is ftri^ly chemical, and not (as 



at firtt might have been imagined) a mixture of particles of 



magnetic iron ore with common pyrites*. 



The compound This is certainly very remarkable} and it induced me to exa- 



direQly formed ^ine the effcds produced by fulphur, on the capacity of me- 

 »t red heat. ,,. . ^ ' . . ,•'/., ^ ^ 



tallic iron tor receivmg and retaining the magnetic properties, 



I therefore prepared fome fulphuret of iron, by adding a large 



quantity of fulphur to fine iron wire, in a moderate red heat. 



♦ This has been fufficiently proved, by the fafts which have been 

 ilated } 1 fliall however add, that upon digefting a mixture of the 

 powder of common pyrites and iron filings in muriatic acid, I only 

 phtained hydrogen gas, exactly «is if I had employed the iron tilings 

 V'itho^it the pyrites. 



The 



