FUSIBILITY 



523 



When 15 percent, of fusel oil is found in alcohol it is admitted duty free; the 

 determination of this is, therefore, a question of considerable importance. The 

 method in use in the London Custom House for the determination of alcohol in 

 fusel oil consists in shaking the liquid to be tested with an equal volume of water, 

 and allowing it to stand twelve hours ; at the expiration of which time it is found 

 separated into two layers, the fusel oil being at the top. The specific gravity of 

 the lower layer is taken, and from this the amount of proof spirit is calculated. 

 This, Dr. Ulex says, leads to very false results, since crude fusel oil contains also 

 ethylic, propylic, butylic, and amylic alcohol, which are variously soluble in water. 

 He recommends the separation .by fractional distillation, and the use of saturated 

 solutions of sodic chloride, (chloride of sodium). He places 100 c. c. of the fusel oil 

 to be tested in a retort, and distils off 5 c. c., and shakes this with an equal quantity 

 of a saturated salt solution. If, on standing, one half or more of the liquid is fusel 

 oil we may be sure it contains less than 15 per cent, of proof spirit, which renders it 

 free of duty in England. If less separates, shake some of the liquor with an equal 

 quantity of brine, and allow it to stand ; after separating, distil the spirit from the 

 salt solution and determine. 



Fusel oil has been patented as a solvent for quinine, but its odour, and more espe- 

 cially that produced by its oxidation, so persistently adheres to anything with which 

 it has been in contact, that great care is requisite in the purification. It is remark- 

 able, that at the first instant of smelling most specimens of fusel oil, the odour is not 

 unpleasant, but in a very few seconds it becomes exceedingly repulsive, and provokes 

 coughing. G. GK W. 



FUSIBILITY. That property by which solids assume the fluid state under the 

 influence of heat. With a few exceptions, such as carbon and some organic bodies, 

 all substances appear capable of assuming the fluid state. Although we do not 

 appear to have actually fused charcoal by means of the voltaic battery, the diamond 

 has been fused and converted from a crystalline gem into a mass of opaque coke. 



Thenard has thus grouped the metals : 



1. Fusible below a red heat : Mercury, potassium, sodium, tin, bismuth, lead, 

 tellurium, arsenic, zinc, antimony, cadmium. 



2. Infusible below a red heat : Silver, copper, gold, cobalt, iron, manganese, nicJcel, 

 palladium, molybdenum, uranium, tungsten, chromium, titanium, cerium, osmium, 

 indium, rhodium, platinum, columbium. 



Pouillet has, in his admirable treatise on Heat, given the following table of the 

 fusing points of various substances : 



Names Centigrade 



Mercury 39 



Oil of Turpentine 10 



Ice . .^ . * 



Tallow 33 to 38 



Acetic acid ......... 45 



Spermaceti 49 



Stearine 49 to 43 



Margaric acid 55 to 60 



Unbleached wax 61 



White wax .* . .' 68 



Stearicacid 70 



Phosphorus \ \ . 43 



Potassium 58 



Sodium .... 90 



Iodine *.*... 107 



Sulphur 114 



Tin . 230 



