Dept.] NATURAL SCIENCES OF PHILADELPHIA. 7 



After thus separating the fatty substances as above, the portion in- 

 soluble in water was placed in a small retort with a little water ; a 

 receiver surrounded with ice was luted to the retort, and heat applied to 

 the latter. On the surface of the distillate a small portion of essential 

 oil floated. This had an odor somewhat resembling that of mustard, but 

 much less pungent. 



The substance remaining in the retort was next dried at a low tempera- 

 ture, and subjected to the action of alcohol. A yellowish-brown solution 

 resulted, from which, on evaporation, a resinoid substance was ob- 

 tained, having an odor very similar to that of a true essential oil. 



The residue was next calcined in a platinum crucible. By this process 

 the woody fibre, &c, was consumed, hydrochloric acid was added to the ash, 

 and the silica thus separated. To a portion of this solution in hydrochlo- 

 ric acid diluted with water, ferrocyanide of potassium was added, and 

 distinct evidence of the presence of iron obtained. Another portion 

 treated with bichloride of platinum gave after a lapse of several hours 

 a reddish crystalline precipitate, indicating the presence of soda. 



We were prevented by an accident continuingthe analysis of the above 

 portion. 



The aqueous solution was found by the addition of gelatin in excess, to 

 yield a flaky, yellowish white precipitate of tannate of gelatine. It was 

 filtered, and to the filtrate perchloride of iron added. A black precipi- 

 tate of gallate of iron was thrown down. 



From the foregoing analysis we conceive that we have ascertained the 

 existencee in corroval. besides, the active principle, of the following sub- 

 stances : Olein, Margarin, Essential Oil, Resin, Starch, Silica, Iron. 

 Soda, Woody Fibre, Tannic Acid, Gallic Acid. 



The small quantity of corroval in our possession, prevented us from ex- 

 tending our analysis further in this direction, and for the same reason we 

 are the less disposed to insist upon the absolute accuracy in all its steps of 

 the foregoing investigation. Several of the above named substances were 

 detected by the microscope alone, and this instrument was constantly 

 employed throughout the whole analysis. 



In the separation of the active principle of the corroval, we made use 

 of the following processes : 



1st. Ten grains of the substance were extracted by repeated portions 

 of boiling water, till a bitter taste was no longer afforded. The solutions 

 were now mixed and boiled with magnesia. It was next filtered, and 

 the filtrate filtered repeatedly through animal charcoal, till all the bitter- 

 ness and coloring matter were entirely absorbed. The charcoal was then 

 treated with boiling alcohol in fresh portions till all bitterness was ex- 

 tracted from it. The alcohol was then evaporated to dryness. By this 

 means a very bitter substance of a greenish white color was obtained, 

 possessed in a high degree of the toxic properties of the corroval. 



2d. The process employed in this instance was that first used by Roulin 

 and Boussingault, but modified by employing water to extract with, 

 instead of alcohol. 



Ten grains of the corroval were reduced to fine powder and extracted 

 with water, as in the first described process. To the solution, tannic acid 

 was added in excess, a voluminous flaky precipitate of a yellowish-white 

 color was thrown down. This was well washed on a filter to remove the 

 tannic acid, mixed with water and heated to boiling, a few crystals of 

 oxalic acid being added till it was entirely dissolved. The acid liquor 

 was next treated with magnesia, in excess, and filtered. The filtrate was 

 18G0.] 



