216 FOSSIL HYDRO-CARBONS — 



share in these great improvements in artificial light, and even the cottager 

 may now take a last farewell of the farthing rushlight, which only helped 

 to intensify the squalid misery of his wretchedness, and substitute in its 

 place a lamp that will, by its vigorous and inspiriting flame, impart an air 

 of cheerfulness around, and, at the same time, prove equally, if not more, 

 economical than its unfortunate predecessor. 



To the fossil hydro-carbons, Society is indebted for most of the very 

 important and beneficial changes in the character of our artificial lights to 

 which I have referred ; and it is quite possible, if not probable, that all our 

 supplies of light, whether in the form of gas, oil, spirit, or candles, may 

 eventually be obtained from this source, to the exclusion of all others. 

 Petroleum, or rock oil, has been burnt in lamps in its crude state in various 

 parts of the world, and by various peoples. The Seneca Indians are 

 reputed to have used the oil in this way, whence we have the synonym 

 " Seneca oil." In Greece also this mineral oil was consumed, as well as by 

 the inhabitants of the Caspian Sea, and its neighbourhood. Cannel coal 

 is another of the fossil hydro-carbons that is immediately available for 

 purposes of light, since, if it be turned into sticks about three-quarters of 

 an inch in diameter, it will burn gradually away like a candle, with a fair 

 flame, from the abundance of volatile matter it contains ; and this, in the 

 absence of any other source of light, would not be without its value. 



Gas, however, was the first illuminating agent ever derived by manu- 

 facture from the fossil hydro-carbons, and its production is now most 

 extensive, and carried to a high pitch of perfection, and it will be improved 

 in quality still further, in consequence of recent legislation on the subject. 

 Gas is too well known to require much notice, and I shall simply describe 

 it as an elastic fluid, highly inflammable, lighter than air, and producing, 

 when ignited, a brilliant flame. Gas can be obtained with facility from 

 either of the fossil hydro-carbons, but at present, coal is the raw material 

 generally employed in its production, although in Ireland peat has been 

 made available for the same end, and might be thus employed to a much 

 greater extent. 



The next important illuminating agents derived from the hydro-carbons, 

 are those kinds of spirituous oil burnt in lamps, which are becoming so popu- 

 lar, and obtained from coal, peat, bituminous shale, and bitumen. These 

 lamp oils are distinguished by a variety of names rather confusing to the 

 general public, each producer, emulous of notoriety, selecting a dis- 

 tinctive by which his own especial production shall be known in the 

 market ; thus we have, — 



From American Rock Oils : — 



Photogene oil — or literally, earth light oil, from <pws, light, and 777, 



the earth. 

 Kerosene oil — literally wax oil, from nypos — Wax, in allusion to 



the solid wax-like Paraflme, these oils contain in them. 

 Crystal oil, in allusion to its clearness and; purity. 

 Petrolene — or rock oil — from irerpos — a rock. 



