ANALYSIS OF ALOES. gaO 



148 grains. [2285 grs.] of watci, at 32P R. [104^ F.] but much more 

 weresufficientfor the complete solution of 4 grain, [gi-g^"^"'^^^"^ ^"^ 

 grs.] of aloes, except a decigr. [1-5 gr.] of impure woody 

 matter. As it cooled, the solution grew turbid, and let 

 fail a portion of the matter dissolved. This solubility of 

 aloes in water is so much increased by heat, that we may 

 obtain a solution of the consistence of a sirup, which then 

 lets fall nothing, and is even capable of crystallizing, on 

 boiling it down still farther. 



., The aqueous solution of alt)cs exhibited the following ap- Propertiesof the 

 pcarances with reasrcnts. aqueous solu- 



1. Infusion ot litmus is very perceptibly reddened by it. 



2. Alkalis and lime-water reader its colour deeper, with- 

 out precipitating any thing. 



3. Sulphate of iron produces in it a brown colour, and 

 in a little time a precipitate of the same hue. 



4. Decoction of galls produces a yellowish flocculent pre- 

 cipitate. The supernatant liquid is paler, and much less 

 |>itter than before. 



r-^; 5. The subacetate of lead likewise occasions a precipitate^ 

 and the supernatant liquid is nearly colourless. 



3. Nitrate of copper and of lead, and muriate of tin, 

 likewise occasion slight depositions; but these do not ap- 

 pear to be real chemical compounds, for the solutions of 

 muriate of soda, and other neutral salts, effect as much. 

 These saline substances therefore act on the solution of aloes 

 in the same manner as on that of tannin in water, merely 

 by weakening the action of this liquid on the difficultly solu- 

 ble matter it contains. 



. . This solution of aloes, which was of a fine gold colour, Action ofairon 



' r^. ,- , . . the solution. 



iBfas left to settle in three vessels. The first, containing a 



quart, was quite filled with it, and well-corked : the second, 

 of the same size, was but half full, and uncorked ; the 

 third, an apothecary's phial, was likewise open, and but a 

 quarter filled. At the end of ten weeks the solution in the 

 first retained its colour unchanged: that in the second was 

 of a very deep red, but rendered colourless by oxirau- 

 riatic acid, which produced in it a flocculent precipitate : 

 in the third, a quantify of mucus was formed. The co- 

 loured liquids in thclast two had acquired a degree of vis- 

 cosity ; 



