30 Historical Sketch of Improvements in [July, 



Hydrocyanic acid dissolves strychnia, and forms with it a 

 crystallizable salt. 



Strychnia neither combines with sulphur nor carbon. When 

 boiled with iodine, a solution takes place, and iodate and hydrio- 

 date of strychnia are formed. Chlorine acts upon it precisely in 

 the same way. 



Strychnia, when dissolved in alcohol, has the property of pre- 

 cipitating the greater number of metallic oxides from their acid 

 solutions. It is precipitated by the alkalies and alkaline earths ; 

 but the effect of the earths proper has not been tried. (See Ann. 

 deCbim.etde Phys.x. 142). 



2. Brncia. — This alkaline substance was obtained by Pelle- 

 tier and Caventou from the bark of the hruca:a antidysenterica, 

 and made known to them about the middle of the year 1819. A 

 brief account of its properties was inserted in the Annals of Phi- 

 losophy for April last. It will be requisite to state in this place 

 its most remarkable characters, that we may have it in our power 

 to compare it with the other alkaline bodies contained in this 

 part of our historical sketch. 



Brucia was obtained from the bark of the bruca^a antidysente- 

 jica by the following process : The bark was first digested in 

 sulphuric ether, and then in alcohol. The alcoholic solution was 

 evaporated to dryness, and the residue was dissolved in water. 

 The brucia, which this solution contained, was saturated with 

 oxalic acid, and the whole evaporated to dryness. This dry 

 residue was digested in alcohol at the temperature of 32°, which 

 dissolved the colouring matter, and left the oxalate of brucia in 

 a state of purity. This oxalate being digested with lime or 

 magnesia was decomposed, the oxalate of lime or magnesia 

 remained undissolved, while the pure brucia dissolved in the 

 water. Brucia thus obtained possesses the following pro- 

 perties : 



It crystalHzes in oblique prisms, with parallelograms for their 

 bases. It is soluble in 500 times its weight of boilmg water, and 

 in 850 times its weight of cold water. This solubility is much 

 increased by the presence of the colouring matter with which 

 brucia is united in the alcoholic solution from the bark of the 

 brucsea antidysenterica. 



Brucia has a very bitter taste, but less so than strychnia ; but 

 it is sharper, more acrid, and continues for a long time. It pro- 

 duces exactly the same effects upon the animal economy, but 

 acts only with one-twelfth of the energy that strychnia does. 

 When exposed to the air it undergoes no change. When 

 heated, it melts, and on cooling congeals into a mass, which has 

 the appearance of wax. Its fusing temperature is a httle higher 

 than the boiling point of water. When strongly heated, it is 

 decomposed, yielding much empyreumatic oil, a httle water, 

 acetic acid, carburetted hydrogen, and a very little carbonic acid. 

 !No trace of ammonia can be discovered among the products. When 



