Action of Sodium and Ethyl-iodide on Acetic Ether. 311 



acetic ether employed. In a quantitative experiment, in which 4*857 

 grammes of acetic ether were acted upon by sodium in slight excess, 

 344-79 cub. centims. of hydrogen at 0° C. and 760 millims. pressure 

 were obtained. If one molecule of acetic ether had lost one atom of 

 hydrogen, 615*9 cub. centims. of gas ought to have been collected. 

 It was evident, however, that a large proportion of acetic ether still 

 remained unattacked at the close of the experiment. 



Such, then, was our mode of operating : the hydrogen evolved 

 was allowed freely to escape, the whole process was conducted at the 

 ordinary atmospheric pressure, and the temperature varied from the 

 boiling-point of acetic ether to 130° C. Moreover the acetic ether 

 used was prepared with the greatest care, so as to ensure the absence 

 of alcohol and water. By our method of preparation, described in 

 the memoir already cited, no traces of the former could be detected 

 even in the crude ether ; nevertheless it was first placed for several 

 days over fragments of fused calcic chloride, which apparently re- 

 mained perfectly dry and unaffected; it was then in some cases 

 boiled for ten days or a fortnight upon many pounds of sodium-amal- 

 gam, which we find to be entirely without action upon pure acetic 

 ether, whilst it rapidly attacks and removes alcohol, if the latter be 

 added even in very small proportion to the acetic ether. When 

 acetic ether, so treated and then distilled from the sodium-amalgam, 

 was brought into contact with the sodium, an abundant evolution of 

 hydrogen immediately commenced, and continued during the entire 

 treatment, which, as already remarked, frequently lasted several days. 

 The general impression, however, produced upon us by the whole of 

 our operations was, that the evolution of hydrogen was not quite so 

 great as that theoretically required by the reactions which we believe 

 to take place ; nevertheless it was obvious that no equations from 

 which free hydrogen was excluded could possibly express correctly 

 the chemical changes effected in this action. Certain experiments 

 were undertaken to trace the missing hydrogen ; but as they have 

 not hitherto been completed, we will not further allude to them here. 



We now turn to Mr. Wanklyn's mode of experimenting. This 

 is not stated in his communication to the Royal Society, but is 

 given in the Journal of the Chemical Society, vol. xvii. p. 371, and 

 in the Ann. Chem. u. Pharm. for January 1869, as follows: — • 



Exp. 1. "I sealed up a quantity of sodium with acetate of ethyl, 

 which had been very carefully deprived of alcohol and water, and 

 weighed the tube containing these materials. I then heated the 

 tube to 130° C. for some time, until the contents had changed from 

 liquid to solid. After opening the tube and allowing any gas that 

 might have formed to escape, I weighed it again. The loss amounted 

 to 0*5 in 100 parts of acetic ether" 



Exp. 2. " 5 cub. centims. of good acetate of ethyl and 0*3 grm. of 

 sodium were sealed up in a small glass tube and heated in a water- 

 bath to 100° C. until all the sodium had disappeared. The tube 

 was then opened under water ; the evolved gas measured 25 cub. 

 centims. at ordinary temperature, but at 0° C. and 760 millims. pres- 

 sure and dry it measured 23 cub. centims. If the volume of hydro- 



