196 Messrs. Erankland and Duppa On the Acids [April 27, 



We have also obtained a beautifully crystalline acid of the same com- 

 position, and perfectly pure, from its zinc-salt, which is contained in the 

 residue remaining after the distillation of the three ethers above described. 

 Amylhydroxalic acid prepared from this zinc-salt is but sparingly soluble 

 in water, from which, however, it crystallizes in magnificent nacreous scales 

 that fuse at 60'5 C., but afterwards remain liquid for some time even at 

 ordinary temperatures ; they are very unctuous to the touch, and readily 

 soluble in alcohol and ether. Several analyses gave results closely corre- 

 sponding with the formula 



rc.H n 



I H 

 OH 



O 

 OH. 



The barium-salt of this acid crystallizes in large and beautiful nacreous 

 scales like paraffin, tolerably soluble in water, and exhibiting the composition 



(C 5 H u ) a 



We have also prepared a copper salt which is deposited from its aqueous 

 solution in the form of minute light-blue scales, very sparingly soluble in 

 water. The numbers obtained by the analysis of this salt agree with the 

 formula 



(C 5 H n ) a 



By the decomposition of ethylic ethyl-amylhydroxalate with alcoholic 

 potash, subsequent addition of sulphuric acid in excess, and treatment with 

 ether, the corresponding acid was obtained as a thick oil, gradually solidify ing 

 to a crystalline mass, which, however, did not appear to be in a fit state for 

 the determination of its fusing-point. We have examined the barium- and 

 silver-salts of this acid, which have respectively the following composition : 



Barium ethyl- Silver ethyl- 



amylhydroxalate. amylhydroxalate. 



Ethylic diamyloxalate is readily decomposed by baryta- water. After 

 removing the excess of baryta in the usual manner, barium diamyloxalate 



