Alkali-metals on the Ethers of the Fatty Acids. 287 



tion in which free hydrogen occurred, and asserted that disen- 

 gagement of hydrogen took place during his experiment. 



Frankland and Duppa confirmed Geuther's formula by pre- 

 paring the ethyle derivative of the soda-salt, and asserted most 

 explicitly the evolution of hydrogen. A marked feature of their 

 investigation is the great prominence given to products of secon- 

 dary action, and the mistaking of them for the primary products. 



It was next pointed out by me that the formula C 6 H 9 NaO 3 

 is equal to three atoms of acetyle and one atom of sodium. It 

 was further shown by me that, during action of alkali-metals 

 on acetic ether, one quarter of the metal enters into a new form 

 of combination, and three quarters form ethylate of the metal. 

 (This was shown both for potassium and for sodium.) It was 

 also shown that, when proper care is taken to employ pure acetic 

 ether and not to allow secondary products to be produced, there is, 

 as Lowig had found in 1840, no disengagement of permanent gas. 



These experimental data warrant, and are expressed by, this 

 equation, 



N* + 8g{[: }0-8C.H.N.0 + (C2H3 a 3 }- 



Although my demonstration of the non-evolution of hydrogen 

 was published so long ago as the summer of 1868, and although 

 I read the paper to Dr. Frankland, who was President of the 

 Chemical Section of the British Association at the time, still no 

 step was taken by Frankland and Duppa until February 1870, 

 when the communication which occasioned the writing of this 

 notice was made to the Royal Society. 



From this communication I gather that Frankland and Duppa 

 are not prepared to withdraw the account which they have pub- 

 lished of the course of the action of sodium on acetic ether, and 

 that they still maintain that changes do take place in which free 

 hydrogen is directly evolved. Their original account, published 

 in 1866, in which they wrote a number of equations, each one 

 expressing an evolution of an equivalent of free hydrogen for 

 every equivalent of sodium consumed, is, however, so far modi- 

 fied that they now appear to admit the occurrence of an accom- 

 panying reaction not involving free hydrogen. So far as I am 

 able to understand their recent paper, they appear to say that at 

 high pressures one kind of reaction takes place between sodium 

 and acetic ether, and at low pressures another kind of action 

 takes place. According to them, my reaction occurs at high 

 pressures and theirs at low pressures. 



However, none of my experiments were conducted at high 

 pressures ; some of them were at the ordinary atmospheric pres- 

 sure ; and I am at a loss to comprehend how such an explanation 



