356 Mr. Henry's Conftderations on different Materials^ 



though it at firft congealed on the furface of 

 the liquor in the receiver, was afterwards dif- 

 folved in it, by means of heat, even though 

 diluted with water,, with which it pafled through 

 the filter. Wool alfo afforded the fame greafy 

 matter, and acid of fugar; the latter in much 

 larger portion than any other fubftance which 

 he treated in the fame manner. But the oil of 

 vegetable fubftances was entirely deftroyed by 

 this treatment, no greafy matter being pro- 

 duced ; and, on analyfing cotton, he procured 

 faccharine acid, but no other produdj and the 

 quantity of that acid was far inferior to that 

 yielded by animal fubftances.* 



It (hould appear, then, that there is a con- 

 fiderable difference between the conftituent parts 

 of animal and vegetable fubftances. Animal 



* M. BerthoUet found the portion of faccharine acid, 

 yielded by cotton to be very fmall indeed ; nor did he 

 find any other refiduum, in the retort, or any thing but 

 the pure nitrous acid, in the receiver. Almoft the whole, 

 therefore, of this vegetable matter, feems to have been 

 changed from a folid, to an aerial form, and to have been 

 diflipated as gas ; a Itate to which ihe faccharine acid is 

 alfo eafily reducible. Thus, fays he, probably, aie the 

 moft folid bodies convertible into elaftic vapours, as on 

 the other hand, the moft compaft fubftances in nature may 

 be formed by the union of different gafes. 



The faccharine acid was nrft difcovered by Bergman, in 

 fugar, but is' obtainable from many other fubftances both 

 animal and vegetable, which Contain its bafis, particularly 

 from galls, which yield it in great abundance. 



fubftances 



