SALTER — A CHRISTMAS LECTURE ON COAL. 
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They are either hydro -carbons or carbo-hydro gens, as the case may 
be. And then there are acid fats, Rosolic, bninolic, carbolic, &c., 
which are likely to test the skill and research of our chemists for 
generations to come. 
We can glance at one or two only of the more important of these 
substances. 
Paraffine, or napthaline, which, as above said, exists in the coal- 
naptha, is, however, more profitably obtained by distillation of the 
celebrated Torbane Hill, or Boghead coal, and some of the Cannel 
coals, at a dull red heat ; though even at this heat only a portion of 
the oil can be retained, the rest going off in the form of coal-gas. 
An analysis of an average specimen of the coal is as follows, side by 
side with an analysis of the pure paraffin itself: — 
Boghead Coal. 
Carbon 60 to 65 per cent. 
Hydrogen ... 7^ to 9 „ 
Earthy matter 20 to 25 „ 
100 parts 
Pure Par a fin. 
Carbon per cent. 
Hydrogen 14f 
Loss or oxygen. . . f „ 
100 parts 
And by this distillation, paraffin oil, naptha, and pure paraffin are 
obtained. The oil, as before said, is used largely for machinery, the 
naptha for light ; so that a railway ti'ain may be driven by the coke, 
lubricated by the oil, and lighted by the naptha obtained from the 
same cwt, of coal. 
From the oil a crystalline substance, which is true paraffin, is 
obtained by cooling, and when purified by vitriol, soda, and warm 
water, yields at last the beautiful candles with which most people are 
now familiar. We can get oil and spermaceti at last without hunting 
out and destroying the lord of the polar seas. 
Such oils and candles are made from other bituminous shales in 
our own country. Those of Caithness are chiefly bituminous remains 
of Old Red Sandstone fish! So Miller and Murchison tell us. 
And his majesty the King of Ava makes most of his pocket-money 
by sending us the " Rangoon tar" for this purpose. 
The only uses that I know of for creasote are curing ham and 
toothache ; for the fluid used for " creasoting" timber is not creasote, 
but pitch-oil. We have done now with these acrid and tarry elements, 
and must say a word on the scented ethers which are found in coal. 
For, strange to say, in this dark compound of ill savour, lie im- 
prisoned fairy scents which rival the breath of flowers. Their full 
history may be found in lire's New Dictionary of Chemistry, or the 
original papers by Prof. Hofiinann, in the Philosophical Journal. 
Prof. Hoffmann himself has been a large discoverer in this, as in all 
other branches of organic chemistry ; and I have heard an anecdote 
of these researches worth recording here. A lady whom he had 
admitted to his laboratory while these essences were being manu- 
factured, was so charmed with the odour of hyacinth, that she forgot 
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