21 6 
Dr. Kidd’s observations 
Does not affect the colour either of litmus or of turmeric. 
Insoluble in cold water ; and very sparingly soluble in 
boiling water, from which it separates, in cooling, in such a 
manner as to render the water milky, which was before 
transparent : a portion however still remains dissolved, for 
the water, when filtered, possesses in a slight degree the 
taste and odour of the substance, and after a few hours de- 
posits it in minute crystals. 
Readily soluble in alcohol, and still more so in ether, at 
any temperature ; the solubility, in either instance, greatly 
increased by increase of temperature. 
A solution of this substance in four times its weight of 
boiling alcohol becomes, in cooling, a solid crystalline mass. 
It is precipitated from its solution in alcohol by water, with- 
out acquiring any additional weight. 
It is soluble in olive oil, and in oil of turpentine. 
It does not combine either with an aqueous solution of pot- 
ash or ammonia ; nor is it sensibly affected by contact with 
ammoniacal gas. 
Soluble in acetic and in oxalic acid, to each of which it 
communicates a clear pink colour. A saturated hot acetic 
solution becomes a solid crystalline mass in cooling. 
It blackens sulphuric acid when boiled in it ; the addition 
of water to the mixture having no other effect than to dilute 
the colour : neither does any precipitation take place upon 
saturating the acid with ammonia. 
Sparingly soluble in hot muriatic acid, to which it com- 
municates a purplish pink colour. 
When boiled in nitric acid, it both decomposes the acid, 
and is itself altered in its composition ; and, in cooling, is 
