434 Of the Adiofi of Vegelahle Acids on Alcohol. 



stvbtifflv concentrating this solution and allowing; it to pur- 

 sue Its natural course. 1 hus, though muriatic acid is not 

 one of the constituents of this singular body, and although 

 the two bodies which form it are in each other's presence, 

 yot it cannot be produced without the assistance of the 

 acid; which result, extraordinary as it mav appear, is 

 nevertheless of the greatest authenticity, as we shall pre- 

 sently endeavour to show : but first let us be satisfied 

 whether the other vegetable acids are similar to the benzoic 

 in their action on alcohol. 



Expenment II. — Having made a solution of 30 grammes 

 of oxalic acid in 36 grains of alcohol, and added lO 

 granimes of concentrated sulphuric acid,^ the mixture was 

 distilled until sulphuric ether began to be formed; it passed 

 into the receiver like alcohol slightly etherized, and it left 

 in the retort a brownish liquor of great acidity, which, on 

 cooling, subsided like crystals of o.xalic acid ; but when 

 water was diflused over this liqnid, a substance separated 

 giinilar to that given by the benzoic acid, slightly soluble 

 in water, produced in a pretty large quantity, and capable 

 of being purified by washing with cold water, and by abs- 

 tracting, by means of a little alkali, the excess of acid re- 

 taii\ed. Treating in the same manner the citric and malic 

 acid?, results pncisclv similar were obtained. The three 

 substances procured from these three acids resemble each 

 other in some of their properties: all are of a yellowish 

 hue, rather heavier than water, destitute of smell, percep- 

 tibly soluble in water, and very soluble in alcohol, from 

 which water precipitates them. In taste they differ : that 

 procured from the oxalic acid is slightly astringent, that 

 from the citric very bitter, but what taste the other ha* 

 I do not know. The first is volatile; it is rather more 

 so than water; by this means it is easily made white. It 

 was particularly interesting to acquire an intimate know- 

 ledge of the nature of all three. I was inclined to believe that 

 their decomposition might be effected by distillation in a 

 solution of caustic potash, ;uul that the first would afford 

 nie oxalic acid, the second citric, and the third malic ; that 

 all would give me alcohol^ and be free from sulphuric 

 acid : the facts were according to mv expectations. Here 

 then we possess new combinations of the vegetable acids 

 and alcohol, in the formation of which the sulphuric acid 

 has performed the same part as the muriatic did in the pre- 

 ceding experiments. 

 / After this, it became very probable that the other vege- 

 table acids acted towards alcohol in the same manner as 



the 



