218 FOSSIL HYDRO-CARBONS — 



that the sp. gr. may be sufficiently high to preclude the possibility of 

 danger. Sometimes makers mis together light oils and heavy oils, so as to 

 average the weight, but this course appears fraught with mischief, for I am 

 informed that a perfect homogeneity of the two fluids does not take place, 

 and that the lighter portion will readily separate by a very slight applica- 

 tion of heat, or even with a warm temperature, and is easily fired. This 

 may possibly explain those few accidents which have occurred with 

 paraffine, and it is a danger which the hydrometer cannot detect. It must, 

 therefore, rest with the makers, thus far, to protect the public ; and 

 inasmuch as the light spirit is now becoming valuable in itself, instead of 

 being a waste product as heretofore, there will be less inducement to prac- 

 tise the eviL When distilled over at the same time, these light and heavy 

 fluids, even if they be not absolutely homogeneous, are notwithstanding so 

 well commingled as to be practically safe. 



Another, and a very beautiful source of light derived from coals, peat, 

 and bitumens, is paraffine, the solid substance from which the oils derive 

 their name. It is separated from the heaviest products of distillation, and 

 in its rough condition has a most offensive smell and dirty color, but when 

 purified it is brilliantly white, and crystalline, not unlike spermaceti, sp. 

 gr. °87, and having a formula C. 20 , H. 91 . In combination with a small 

 proportion of animal or vegetable stearine, paraffine forms achnirable 

 candles of a semi-transparent nature, and more attractive to the eye than 

 the best wax lights. It has been clearly demonstrated that all paraffines, 

 although possessing exactly the same composition and chemical formula, 

 are not alike in their fusing point, the range being from 108° to 140 a 

 Fahrenheit, a most important fact in the application of this beautiful sub- 

 stance to the manufacture of candles, since it becomes apparent that whereas 

 some paraffine candles would be suitable for the high temperature prevail- 

 ing at the tropics, others would be melting and softening in such a way as 

 to produce complete condemnation of paraffine for warm climates. 



Paraffine candles are sometimes greatly adulterated with chalk and other 

 substances, especially those received from abroad. 



Heat. 

 To the denizens of a cold and moist climate, a warm fireside is a necessity 

 and a luxury of no little value. The wood-fire on the hearth, around which 

 our ancestors gathered, has been necessarily superseded by the iron stove 

 and fossil fuel, and the cheerful aspect of our open grates, with their bright 

 and glowing piles of burning coal, is as great a comfort to our own people as 

 it is a subject of admiration to foreigners accustomed to the closed and half- 

 suffocating stoves of Continental houses. But a very small proportion, 

 however, of the fossil hydro-carbons consumed in this country for the pro- 

 duction of heat, are expended in cheering the family hearth, or cooking 

 the family provender. It is the furnaces of England's busy factories and 

 smelting yards, of her locomotives and steam-vessels, that absorb the great 

 bulk of fuel raised from our practically inexhaustible stores. Millions of 



