144 Analyses of Boohs* [Feb. 



" It does not very readily evaporate at the common atmosphe- 

 rical temperature ; for, a comparison being made between this 

 substance and camphor, in the quantity of half a grain of each in 

 a very minute state of division, it was found that the camphor 

 had entirely disappeared at the end of 18 hours, while the sub- 

 stance in question had not disappeared entirely at the end of four 

 days. 



" A quantity of it being exposed to heat in a glass vessel soon 

 melted ; but did not begin to boil till the temperature had reached 

 410° of Fahrenheit : the heat being then withdrawn, it remained 

 liquid till cooled down to J 80° ; at which point the lowest por- 

 tion was seen suddenly to congeal : the remaining portion con- 

 gealed gradually ; and when the whole had become solid, its 

 temperature was 170°. The structure of the congealed mass 

 was distinctly crystalline, and the crystalline laminae were 

 shghtly flexible. 



** It is not very readily inflamed ; but when inflamed, it burns 

 rapidly, and emits an unusually copious and dense smoke, which 

 soon breaks into distinct particles that fall down in every 

 direction. 



** Does not affect the colour either of litmus or of turmeric. 



" Insoluble in cold water ; and very sparingly soluble in boil- 

 ing 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 deposits it in minute crystals. 



** Readily soluble in alcohol, and still more so in ether, at any 

 temperature ; the solubihty, in either instance, greatly increased 

 by increase of temperature. 



" A solution of this substance in four times its weight of boil- 

 ing alcohol becomes, in coohng, a solid crystalhne mass. It is 

 precipitated from its solution in alcohol by water, without acquir- 

 ing any additional weight. 



" It is soluble in olive oil, and in oil of turpentine. 



*' It does not combine either with an aqueous solution of 

 potash 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 solu- 

 tion 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 saturat- 

 ing the acid with ammonia. 



" Sparingly soluble in hot muriatic acid, to which it commu- 

 nicates a purplish pink colour. 



** When boiled in nitric acid, it both decomposes the acid, 

 and is itself altered in its composition ; and, in coohng, isabun- 



