of the Seed of Croton Tiglium. 233 



somewhat concave on one side, and convex on the other ; and they 

 are of a brownish yellow colour. The leaves are pointed, nerved, 

 serrated, supported on long petioles, and stand in alternate order *. 

 But, to return to the object of this communication, I would ob- 

 serve, that I found that the expressed oil of the seed of this plant 

 was entirely soluble in aether and the oil of turpentine, and par- 

 tially so in alcohol. One hundred grains of the seed consisted of 



32 shell 

 68 kernel 



One hundred grains of the seed were digested in three drachms of 

 sulphuric aether, sp. grav. 71, and afforded 25 grains of fixed oil. 



Thirty-two grains of the oil were put into a Florence flask, con* 

 taining some alcohol previously digested on olive oil (as recom- 

 mended in a former Number of your Journal), to prevent (as it is 

 stated in the experiment alluded to) the spirit from dissolving any 

 of the oil of the croton tiglium seed. The mixture was now agi- 

 tated, and then passed through a filter containing carbonate of 

 magnesia. The filtered solution was now evaporated without heat, 

 and yielded— 



Active matter (soluble in alcohol and aether) 

 combined with a very small portion of G „ 

 fixed oil 8.5 



Inert fixed oil 23.5 



32 grains. 



It would appear from some experiments lately made in the manner 



above practised, that one hundred grains of the oil of the tiglium 



seed afforded forty-five grains of active matter, but I must confess 



that I cannot find any sample of oil that will furnish so great a 



per centage. Now as olive oil is not by any means so soluble in 



alcohol as castor oil, incorrect results must ensue, in consequence 



of the alcohol not being fully saturated with a fixed oil prior to its 



mixture with the expressed oil of the seed of croton tiglium. In 



order, therefore, to obviate this objection, I proceeded in the fol- 



* Croton tiglium foliis ovatis, accuminatis, serratis, basi biglandulosis peti- 

 plis, folio brevioribns, racemis terminalibus. — Vide Linn* Spec. Plantar. 



