Organic Bodies containing Metals. 



253 



of methyle ready formed in this body ; and Kolbe *, in developing 

 his views on the so-called conjugate compounds, has proposed to 

 regard it as arsenic conjugated with two atoms of methyle 

 ((C^H^j^As). So long as cacodyle was an isolated example of 

 an organo -metallic body, this view of its rational composition, 

 harmonizing as it did so well with the facts elicited during the 

 route of cacodyle through its various combinations and decom- 

 positions, could scarcely be contested ; but now, since we have 

 become acquainted with the properties and reactions of a con- 

 siderable number of analogous bodies, circumstances arise which 

 I consider militate greatly against this view, if they do not render 

 it absolutely untenable. According to the theory of conjugate 

 radicals just alluded to, cacodyle and its congeners, so far as 

 they are at present known, would be thus represented : — 



Cacodyle [C^Wfks. 



Oxide of cacodyle [Q'^B.^fk^O. 



Cacodylic acid (C^H^j^AsO^. 



Stanmethylium (C^H^jSn. 



Stansethylium (C^H^jSn. 



Oxide of stansethylium .... (C'^H^jSnO. 



Stanamylium (CiOHiijgn^ 



Zincmethylium [C^W)Zxi. 



Zincsethylium (C*H5)Zn. 



Zincamylium (C^OHi^jZu. 



Stibsethine (stib^thyle) .... (C4H5)3Sb. 



Binoxide of stibsethine . •. . . (C^H^j^SbO^. 



Oxide of stibmethylium .... (C2H3)4SbO. 



Hydrargyromethylium .... {Q^ H^) Hg. 



Iodide of hydrargyromethylium . (C^ H^) Hgl. 



It is generally admitted, that when a body becomes conju- 

 gated, its essential chemical character is not altered by the pre- 

 sence of the conjunct : thus for instance, the series of acids 

 C°H"04, formed by the conjunction of the radicals C^H^""-'^ 

 with oxalic acid, have the same neutrahzing power as the original 

 oxalic acidj and, therefore, if we assume the organo-metallic 

 bodies above mentioned to be metals conjugated with various 

 hydrocarbons, we might reasonably expect that the chemical 

 relations of the metal to oxygen, chlorine, sulphur, &c. would 

 remain unchanged ; a glance at the formulae of these compounds 

 will however suffice to show us that this is far from being the 

 case : it is true that cacodyle forms protoxide of 'cacodyle and 

 cacodylic acid, corresponding the one to a somewhat hypothetical 

 protoxide of arsenic, which, if it exist, does not seem to possess 

 any well-defined basic character, and the other to arsenious acid ; 

 * Journal of the Chemical Society, vol. iii. p. 372. 



