176 Miscellaneous Intelligence. 



and perfectly secures the part covered with it, from the action of 

 the menstruum. — Tech. Rep. vi, 134. 



10, Active principle of the Upas Poison. — M.M. Pelletier and 

 Caventou, after various trials to obtain the active principle of the 

 Upas tieute, and suspicious of its nature, adopted the following. 

 An aqueous solution was prepared, which, when filtered, was 

 treated with pure calcined magnesia; the reddish-yellow precipitate 

 obtained, wlien washed and dried, was boiled in alcohol two or 

 three times, and the solutions evaporated, gave an orange-coloured 

 crystalline substance. This substance was bitter, only slightly 

 soluble in water, very soluble in acids, and had all the properties 

 of strychnia, except that of producing a green colour with nitric 

 acid instead of a red one ; but this effect was occasioned by the 

 presence of a brown-coloured substance, for when a solution of the 

 whole was made in weak sulphuric acid, passed through ani- 

 mal charcoal, precipitated by magnesia, and then dissolved in 

 alcohol, and crystallized by slow evaporation, it lost the property 

 of becoming green by nitric acid, and was perfectly pure. 



In this state, it consisted of crystalline prismatic needles, nearly 

 insoluble in water, very bitter, restoring the blue of reddened 

 litmus paper, saturating acids, and with them forming solutions, 

 in which ammonia, tincture of calls, and the alkaline gallates and 

 oxalates, produced precipitates, soluble in alcohol ; and in all 

 things, except that of reddening by nitric acid, exactly resembling 

 strychnia. The red colour, by nitric acid, belongs, therefore, to 

 some other substance than strychnia, and on evaporating the water 

 with which the magnesian precipitate was washed, a yellow sub- 

 stance, having this property, was obtained ; and which redissolved, 

 filtered through animal ciiarcoal, and re-evaporated, gave a tole- 

 rably pure solution of the substance. This substance is uncrystal- 

 lizable, fixed, soluble in water and alcohol, and not precipitable 

 by acetate of lead ; it exists only in small quantities in the upas. 



In consequence of the purity of the strychnia obtained from the 

 upas, specimens were exammed from other sources, and it was as- 

 certained that though most of them reddened by nitric acid, yet 

 they varied in the extent of this property, and one very pure spe- 

 cimen scarcely exhibited the eftect at ail ; hence, it may be con- 

 cluded that the red colour is always due to a portion of impurity 

 accompanying the strychnia, and does not belong to the alkali. 



The strychnia, from the upas, produced all the effects on the 

 animal economy that are produced by strychnia otherwise obtained. 



The brown substance which produces a green colour with nitric 

 acid, was found to be the same as that existing in the false angus- 

 tura bark ; when pure, it is without taste, but slightly soluble in 

 water, darkened in colour by alkalies, and rendered a little more 

 soluble. It dissolves in alcohol, and by evaporation, forms mica- 

 ceous crystalline plates ; it is very slightly soluble in ether or vola- 



I 



