SOLVENTS. 317 



and though a good drier, sometimes fails in its action 

 because it is too strong. Ordinary druggists' alcohol of 

 85 per cent, is an excellent solvent for resins, camphor, 

 tannin, the balsams, iodine, acetic acid, and castor oil, but 

 the ordinary " spirits of wine," consisting of equal volumes 

 of druggists' alcohol and water, has not the same solvent 

 action for resinous matters. Methylated spirit consists of 

 ordinary alcohol, mixed with 10 per cent, of wood-spirit, 

 and is capable of being put to the use of ordinary alcohol 

 by the microscopist. 



Benzol is a colourless, strongly refracting liquid, of a 

 very inflammable nature. It is almost insoluble in water, 

 but dissolves freely in alcohol and ether. It dissolves 

 iodine, sulphur, fats, gum-resins, and many other com- 

 pounds, such as caoutchouc and guttapercha. 



Petroleum naphtha, called also benzoline, benzine, gaso- 

 line, &c., is nearly as useful as coal-tar benzol for the 

 purposes of the microscopist, provided it be of good quality 

 and does not contain any quantity of heavy oils. 



Glycerine is a solvent strongly recommended for general 

 use by Dr. Beale. It is soluble in all proportions in water 

 and alcohol, though it is but sparingly soluble in ether. 

 It dissolves nearly all organic substances soluble in water, 

 and many of those soluble in alcohol ; it dissolves small 

 quantities of carbonate of lime and many oxides ; 20 per 

 cent, of arsenious acid, and 10 per cent, of tannic acid, form- 

 ing with this latter a waxy solid, melting at the temperature 

 of the body, which the author has used sometimes for 

 mounting purposes. 



Oil of cloves is often used as an intermediate bath 

 between alcohol and Canada balsam ; it serves to take out 

 the alcohol, with which the oil changes place. One volume 

 of oil of cloves dissolves an equal volume of alcohol. 



Oil of cajeput is often recommended for use in place of 



