374 Mr A. Galletly on certain 



naphthas and spirit of wine, characteristic of the ordinary 

 pine resins. Like tlie latter, they also creep up the sides 

 of the evaporating basin into globules, and when heated 

 on a spatula give the characteristic pine resin odour. Some 

 at least of these naphtha extracts become much deepened 

 in colour by standing for days in an open porcelain basin 

 occasionally wetted with methylated spirit. 



Compared with alcohol, ether takes out a small propor- 

 tion of resinous matter, but both extracts are highly 

 coloured. The probability is that the natural process of 

 oxidation converts the one into the other, and that if the 

 ether extracts were exposed for a sufficient time to the 

 action of the atmosphere it would have the same properties 

 as the alcoholic extract. Eesinous colouring matters 

 generally are liable to oxidation, causing slight alterations 

 in their properties. 



The alcoholic extract, which is of the same character 

 in all the rosewoods, is the most important, the relative 

 proportion of it being high compared with the naphtha and 

 ether extracts. When the last traces of the spirit are 

 evaporated it is a dark, brittle substance, which easily 

 scales off the evaporating basin. This substance has been 

 tested with the solvents usually employed for dissolving 

 resins, colouring matters as well as fatty and waxy bodies, 

 and its behaviour in this respect is quite peculiar. It is — 



1. Insoluble in benzole. 



2. Insoluble in bisulphide of carbon. 



3. Insoluble in spirit of turpentine. 



4. Insoluble in warm olive oil. 



5. Slightly soluble in hot acetic acid. 



6. Soluble in chloroform. 



7. Very soluble in acetone. 



[The ether extract has the same characters.] 



The properties of this rosewood extract, as shown by its 

 different solubilities, distinguish it, so far as is known, from 

 that of other woods, although mahogany extract in some 

 points resemble it. It is rare to find any substance, 

 belonging to the class of bodies just mentioned, so entirely 

 insoluble in some of these solvents and so readily soluble 

 in others. Substances of a resinous character generally, 



