ACTION OF MURIATIC ACID ON SUGAR. 223 



gas. But if we obtain such evidence, then it at once follows, 

 that this acid is a compound body ; and that its disappear- 

 ance, when made to act upon sugar, is owing to its ultimate 

 decomposition. To ascertain this important point, after 

 adopting several methods, I was led finally to pitch upon 

 the following as the most susceptible' of accuracy. The 

 apparatus made use of for this purpose differed from the 

 former only by a substitution of a tubulated retort for a 

 common one. 



Sect. III. 1st. One hundred grains of muriatic acid of 

 the spec. grav. 1-050 were poured upon 50 grs of dry sugar, 

 previously weighed and introduced into the retort. The 

 apparatus was joined, and found to be perfectly air tight. 

 After the sugar was dissolved, heat was applied to the retort, 

 till about QO grains of liquid were distilled over into the 

 receiver. After the apparatus had become cool by several 

 hours standing, the 90 grs just mentioned were poured back 

 upon the carbonaceous matter in the retort, and again dis- 

 tilled in this manner five times, till finally heat was applied 

 to the retort several hours, to drive off all the adhering acid. 

 Care was taken in all this operation not to disjoin the appa- 

 ratus, till it had been cool for some time, lest some vapour 

 might rush out, and falsify the results. No extra gas passed 

 over into the air holder, nor had the least sensible quantity 

 of muriatic gas become condensed by its water, for it afforded 

 no muriate with nitrate of silver. 



2d. The liquid condensed in the receiver weighed 128 grs. 

 Its colour whs a reddish brown: its taste extremely acid : 

 its smell that of aromatic vinegar nearly. 



3d. The substance in the retort was tasteless. Water 

 dissolved no part of it, but acquired an acid taste from a 

 number of drops condensed in the neck of the retort*. The 

 whole was thrown upon a filter to separate the carbon, which 

 weighed, after being well washed and dried at 170° or 180° 

 for some time, 18 grs. The liquid, which passed through, 

 weighing 550 grs, gave a precipitate with sulphate of silver 

 weighing 1*375. 



* It contained neither a trace of malic acid nor a vestige of untie- 

 composed sugar. The successive distillations having been with the 

 presence of muriatic acid capable of decomposing both. 



4th, 



