220 Professor How on the Ethers and 



took place in twelve hours. Somewhat to my surprise, the 

 reaction proved to be identical in products to the former ; from 

 a liquid containing hydrochloric acid a deposit of needles and 

 grains fell. The needles, when separated as before, gave these 

 numbers : — 



r 5-667 grains, dried at 212°, gave 

 < 10 720 ... carbonic acid, and 

 ( 2-400 ... water. 



equal to a percentage of 



Carbon, . . 51-60 



Hydrogen, . . 4 90 



which approach so nearly to the last results, as to admit of no 

 doubt that they relate to the same substance, though not so 

 pure as was before analysed ; the reaction, I apprehend, being 



HO j C 12 H 2 ° 8 + Cl0 Hl1 Cl + C 4 H 6 2 = C H O j 



C 12 H 2 O 8 + C 10 H 12 O 2 + HCl. 



Meconic acid, as might have been anticipated, is found to be- 

 have in the same manner as comenic acid, with iodide of ethyl. 

 At 212°, in four or five hours it is converted into the same 

 substances, carbonic acid being produced, which causes the 

 tube to open with a lively explosion on its being cut with a 

 file. 



The grains alluded to above were never obtained in suffi- 

 cient quantity, or in a state pure enough for analysis, but the 

 tendency they had to reduce the percentage of carbon and hy- 

 drogen was remarked in some unsuccessful analyses of the 

 needles, not quoted on that account. They consisted of an acid 

 substance which dissolved in boiling water with great ease, and 

 came down upon cooling in the same peculiar granular form. 

 This character separates them from comenic acid, which I at 

 first supposed them to be, and reminds one of the paracomenic 

 acid of Stenhouse, which has, according to this chemist, the 

 same composition. The formation of the para-acid, in this 

 case, would be quite analogous to that of the change under- 

 gone by malic acid when heated with water. 



I attempted to ascertain whether comenic acid really under- 

 goes this alteration in a heated sealed tube with water. I 



