218 Professor How on the Ethers and 



above that of neutral salts, and yet not enough to correspond 

 ■with any other atomic expression. 



Triethylated Meconic Acid? — In my former paper on me- 

 conic acid, I shewed that when it is distilled with absolute al- 

 cohol and a small quantity of oil of vitriol, the biethylated 

 meconic acid is produced. If the proportion of sulphuric acid 

 be much increased in this process, none of the second ether is 

 obtained ; dilution of the contents of the retort throwing down a 

 black oily mass of very different characters. It is excessively 

 soluble in spirit, and is again thrown down as black oil by 

 water. I did not analyse this substance, but think it may 

 possibly be the triethylated meconic acid. 



3C 4 H 5 ? C 14 HO u . 



Digestion with ammonia at a gentle heat converts it into a 

 blackish brown powder — the corresponding amide \ 



Action of Iodide of Ethyl on Comenic Acid. 



Ethylocomenic (Comenovinic) Acid. — When comenic acid 

 in fine powder is heated with spirit of wine and iodide of ethyl 

 in a sealed tube, at 212°, it dissolves, though very slowly, and 

 a fortnight's continued application of this heat is required to 

 effect the solution of a few grains. The product of the reac- 

 tion consists of two substances ; and as I found the same re- 

 sult, to all appearance, to be brought about more speedily at a 

 higher temperature, I at once resorted to this method. 



About 70 grains of the powdered acid were heated with a 

 few fluid drachms of rectified spirit and a little iodide of ethyl, 

 in a close tube, to nearly 350° Fahr. ; solution was complete 

 in two hours. The vessel gave no deposit upon being then 

 allowed to stand cold for twenty-four hours, but directly it was 

 cut open, a slight explosion occurred, and crystals began to 

 form, increasing so rapidly in quantity as speedily to render 

 the whole interior solid. These crystals were in the shape of 

 prismatic needles, with minute, rounded, opaque grains among 

 and upon them, here and there throughout their mass. They 

 were thrown upon a filter, and their mother liquor, which was 

 very dark-coloured, and contained much hydriodic acid, was 



