522 Chronicles of Science. [July, 
1862, 10,887,000 gallons. The total production in 1863 is estimated 
at 80,000,000 gallons. 
The greater proportion is obtained from Oil Creek Valley in Penn- 
sylvania. Many of the borings are 500 feet deep, though some much 
less deep have yielded largely. These latter, however, required 
pumps, while the former, called “ flowing wells,” eject their conterts in 
some cases to a height of 100 feet above the ground. The petroleum 
is discharged by pipes into vats, where the salt water with which it is 
associated separates. In this state it is worth about fourpence a 
gallon, though there have been occasions, when the market was glutted, 
in which it has sold for not more than two shillings a barrel of 40 
gallons. The owners of the wells are now able to control the dis- 
charge by stopcocks fixed on the pipes that line the borings, and 
when the price is low, limit the supply. 
Crude petroleum has to be submitted to distillation in order to 
separate the benzine, which boils at 140° F. from the heavier oils, and 
these, in their turn, from the solid hydrocarbons. The proportion of 
these ingredients varies so greatly (some wells producing so large a 
percentage of the heavy oils), that the product is only suitable for 
greasing machinery. Unfortunately, it “ gums,’ as mechanics say, and 
unless tallow or animal oils are added to it, it cannot replace sperm 
oil. 
The exact source of petroleum is, up to the present, uncertain, 
whether it has all been produced by distillation from bituminous 
coal, anthracite being formed at the same time, or whether it has 
resulted directly from the bituminous fermentation of marine plants 
antedating the coal and containing a larger proportion of hydrogen. 
The amount thrown out by some of the wells is enormous. One 
of them ejected 3,740 barrels a day, three 1,000 barrels, one 800 
barrels. To “strike ile,” has become throughout that region the 
synonym for rapidly growing wealthy. ‘Transportation to market is 
effected by carrying it down the stream in vessels, many of which are 
merely tanks. Occasionally, when collisions occur, thousands of 
gallons are lost, floating away on the surface of the water. It is pro- 
posed to collect the fluid again by means of floating dams, shaped like 
a V, with the point up stream. 
The effect that this illuminating agent has produced throughout 
the country is very striking. It has entirely displaced all other means 
of lighting, except gas, and is used even in cities by many who desire 
an absolutely steady light. The great desideratum is, a perfect chim- 
neyless burner. The petroleum requires a large amount of air for 
complete combustion of its carbon, and by no other means than a tube 
6 or 8 inches long has the supply been rendered sufficient. Although 
by the substitution of mica for glass the difficulty of breakage has to a 
certain extent been overcome, there is still great room for improve- 
ment. 
Kerosene, as the oil suited for burning is called, has in one sense 
increased the length of life among the agricultural population. Those 
who, on account of the dearness and inefficiency of whale oil, were 
accustomed to go to bed soon after sunset, and spend almost half their 
