316 MESSRS. E. FBANKLAND AND B. ¥. DUPPA'S 



atom of that element ; and it is this further absorption that constitutes the second stage 

 above referred to, resulting in the production of zincic ethylate, 



Zn" Et Eto + O = Zn" EtOa- 

 Wanklyn* was the first clearly to point out the probable existence of zincmonethyl, 

 or rather its homologue zincmonomethyl, indicating at the same time its radical function, 

 when he ascribed to the crystalline compound obtained in the preparation of zincmethyl 

 the formula 



In the same memoir he also represented this compound as the analogue of mercuric 

 methiodide, 



Hg" ^^ 



BuTLEEOwJ has also prominently drawn attention to this behaviour of organic zinc com- 

 pounds, and has succeeded in obtaining zincmethylo-methylate, 



Zn" Me Meo 



in a condition approaching to purity by passing a stream of dry air through a solution 

 of zincmethyl in methylic iodide. Butlerow's success in obtaining this body, and his 

 failure in converting it into zincmethylate, are both probably due to the comparative inso- 

 lubility of zincmethylo-methylate in methylic iodide, owing to which the first product 

 of oxidation was to a great extent protected from the further action of oxygen. When, 

 however, ether is used as the solvent in the case of zincethyl, the oxidized product 

 remains in solution till the first stage is passed, after which zincethylate is gradually 

 precipitated until the second stage is completed. Indeed, as has been shown in the 

 memoir above referred to (Philosophical Transactions, 1855, p. 268), the oxidation, 

 instead of stopping at the first stage, proceeds even somewhat further than the second, 

 and the final product formed does not possess a composition in any degree approaching 

 that which Butlerow asserts it to have. This is evident from the following numbers, 

 and from the circumstance that it does not effervesce in the slightest degree when mixed 



with water : — 



Percentage composition according Percentage composition according 



to BuTLEKow's formula, Zn" ^^^W . ^° '"^^'^ "^ '^°'^y^^« §• 



C 34-53 25-48 



H 7-20 5-32 



Zn 46-76 42-04 



O 11-51 27-21 



100-00 100-00 



When ethylic diethoxalate is treated with solution of baric hydrate, it gradually 



» Joum. Chem. Soc. 1861, p. 127. t Zn=32-5 in this formula. 



t Bui. Soc. Chimique, 1864, p. 116. § Philosophical Transactions, 1855, p. 268. 



