ON ACETIC ACID AND ACETATES. 343 



In this table it may be remarked, that the specific gravity Anomaly in 

 of the product of the distillation of acetate of silver is b*t*®*^ tatc of 

 1*0656, while its degree of acidity greatly exceeds that of the 

 rest: yet it does not contain any sensible portion of pyro- 

 acetic spirit. At first I suspected, that this product might 

 contain some other vegetable acid, beside the acetic: and I 

 had not to choose among a great number, for few would 

 have resisted the heat this product had nndergone without 

 being decomposed or volatilized. I saturated a portion 

 with potash, and sought in vain for some other acid. I 

 chiefly expected to find in it pyrotartaric acid, but 

 it did not form the least precipitate with acetate of 

 lead. 



This fact may be explained by the tendency the concen- 

 trated acetic acid has to become solid, and the expansion it 

 would undergo a little before the instant of congelation, ana- 

 logous to what sir Charles Blagden observed in water. I 

 exposed to the same temperature the products of the dis- 

 tilled acetates of silver, nickel, and copper, and that from 

 silver crystallized first. It was likewise the last liquefied on 

 raising the temperature anew; which tends slightly to support 

 the explanation I have given. 



With 15 gram. [232 grs.] of the liquid product of Specific gravity 

 the distillation of the acetate of silver I mingled water bya c ° om p ^J s of 

 gramme at a time. The specific gravity went on in- the acid from it 

 creasing, till three grammes of water had been added, mthwater * 

 when it was 1*0733; and the degree of its acidity, 

 according to the component parts, 76*8959. With five 

 grammes of water the spec. grav. was 1*0693. From 

 five grammes to ten there appeared to me some slight 

 variation ; but beyond that proportion, when it was 

 1*0597, it decreased uniformly. I had, no opportunity 

 of examining this series of mixtures but once, but it ap- 

 pears to favour my opinion. It must be confessed how- 

 ever, that the effect is very great to be produced by so 

 slight a cause. 



This part of my researches however I have not examined Mixtures of 



sufficiently to decide. It is to be wished, that the exact acetic *** f. nd 



, . , - water should 



ratios between the specific gravity and acidity of a liquor bo examined. 



containing 



