99 



2. On Meconic Acid, and some of its Derivatives. By Mr 

 Henry How. Communicated by Dr T. Anderson. 



The author commenced his paper by observing that it formed a 

 sequel to one communicated to the Society last Session on comenic 

 acid ; his object in the present instance having been partly to ascer- 

 tain whether some of the substances described in his former paper 

 could not be derived from meconic acid, which is the parent acid of 

 comenic acid. This he shewed to be the case ; but before detailing 

 these experiments, he gave his process for purifying meconic acid, 

 which is that of Gregory, modified by the use of ammonia instead 

 of potass. Some grounds for preference of this plan were offered, 

 and the composition of the salt obtained in the process was shewn 

 to be 



2 NH,0, HO, C,, HOj^. 



It is a salt crystallising from hot water in groupes of needles ; is 

 not decomposed at the heat of boiling water by itself, but when 

 kept long at this temperature, in presence of ammonia, it produces 

 the comenamic acid, 



HO, C,2 H, NO,, 

 formerly described by the author as a product of the decomposition 

 of comenate of ammonia in the same manner. 



The action of chlorine on this salt gave rise, in the first place, to 

 another acid salt of ammonia and meconic acid, 

 2 HO, NH,0, C,, H0,„ 

 and, as a further product, chlorocomenic acid was isolated. Bromine 

 gave with meconic acid bromocomenic acid ; three experiments shew- 

 ing that meconic acid itself yields no substitution products, its mole- 

 cule splitting into carbonic acid, and the above-mentioned derivatives 

 of comenic acid. 



The action of hydrochloric acid gas on solution of meconic acid 

 in alcohol was next gone into ; and it appears that three products 

 are formed, their relative proportions depending on the amount of 

 gas employed, and the strength of the alcohol. They are all ethers. 

 The first is the ethylomeconic acid, represented by the formula 



2 HO, C, H,0 Cj, HO,,. 

 It is a crystalline substance, soluble in water, alcohol, and ether ; 

 fusible at 316'' Fahr. to a yellow fluid. It is possessed of acid pro- 

 perties, and is indeed bibasic, forming two series of salts ; this was 



