6i Kxpsrlments and Remarks on a Sulstance 



were somewhat remarkable, I shall here more particularly 

 relate them. One hundred grams of pure dragon's blood, 

 reduced to powder, were digested in a long matrass with one 

 Ounce of strong nitric acid ; the colour immediately changed 

 to deep velluw, much nitrous gas was evolved, and to abate 

 the effervescence one ounce of water was added. The di- 

 gestion was continued until a deep yellow dry mass re- 

 mained; and the matrass being still kept in the sand-bath, a 

 brilliant feather-like sublimate arose, which weighed rather 

 more than six grains, and had the aspect, odour, and pro- 

 perties of benzoic acid *. 



The residuum was of a brou'n colour, and with water 

 formed a golden yellow-coloured solution, which by nitrate 

 of lime was not affected. 



With sulphate of iron it afforded a brownish-yellow pre- 

 cipitate. 



With muriate of tin the result was similar. 



With acetite of lead a lemon-coloured precipitate was 

 produced. 



Gold was precipitated by it in the metallic state, whilst the 

 glass vessel acquired a tinge of purple : 



And dissolved isinglass produced a deep yellow deposit, 

 which was insoluble in boiling water. 



A portion of the same dragon's blood was simply exposed 

 to heat in the same matrass, but not any appearance of ben- 

 zoic acid could be discovered. I am therefore induced to 

 'believe, that in the first experiment it was obtained as a pro- 

 duct, and not as an educt : a fact which as yet has not been 

 suspected. 



G. Gum ammoniac afforded a brownish yellow solution, 

 the flavour of which was very bitter and astringent. 



By sulphate of iron, this solution only became of a darker 

 colour, but did not form any precipitate. 



* According to these experiments, dragon's blood ouglit to be arranged 

 with bciizo n and the balsams; but as the samples of this drug are not always 

 preciscljr similar, it would be proper to examine every variety. That which 

 was employed in iry experiments, was a porous mass of a dark red, and 

 was sent to me by Messrs, Allen and Howard, of Plough-court, in Lom- 

 bard street. 



Nitrate 



