1865.] of the Lactic Series. 83 



It was obviously impossible to collect in a state of purity the iodide of 

 ethyl thus set at liberty without considerable loss ; but the quantity of the 

 pure iodide actually obtained was 12 grms. The abore equation requires 

 14-6 grms. 



On the removal of ether and iodide of ethyl, the mixture of zincoleucic 

 ether and iodide of zinc forms a transparent gummy mass easily soluble 

 in ether, bisulphide of carbon, and caoutchoucin, but totally incapable of 

 crystallizing from any of its solutions. All our attempts to separate these 

 bodies have hitherto proved abortive, and it is by no means improbable 

 that they are chemically combined. 



The action of zincethyl upon ethylic leucate throws much light upon 

 the production of the latter from zincethyl and ethylic oxalate, and scarcely 

 leaves a doubt that, when zincethyl is added to ethylic leucate, there is 

 reproduced the zinc compound from which the ethylic leucate was first 

 formed. We may therefore express the two stages in the original produc- 

 tion of ethylic leucate by the following equations : 



L O C 2 H. [ O C a H. Zh.cethylo-ethylate. 



Ethylic oxalate. Zincmonethyl-ethylic 



leucate. 



(C 2 _H 5 ) 2 



Zinc hydrate. 



Zincmonethyl-ethylic Ethylic leucate. 



leucate. 



III. " Notes of Researches on the Acids of the Lactic Series. No. IV. 

 Action of Zinc upon Oxalic Ether and the Iodides of Methyl and 

 Ethyl mixed in atomic proportions." By E. FRANKLAND, F.R.S. 

 and B. F. DUPPA, Esq. Received February 2, 1865. 



The reaction of zinc upon oxalic ether in the presence of iodide of amyl, 

 the results of which we hope very shortly to have the honour of laying 

 before the Royal Society, had led us to anticipate, that if an oxalate of one 

 organic radical were treated with the iodide of another, one atom of di- 

 atomic oxygen in the oxalic ether would be replaced by two different mon- 

 atomic radicals. This anticipation was not, however, realized, as we have 

 already shown*, when the reaction was extended to a mixture of iodide of 

 ethyl with oxalate of methyl, and iodide of methyl with oxalate of ethyl. 

 In both these cases the radicals presented in the form of iodides were the 

 * Proceedings of the Royal Society, vol. xiv. p. 17. 



