use in several localities in eastern Ohio for twenty-five years, and the
wells are flowing as vigorously as when first known. It has also been
in use in West Virginia for a quarter of a century, as well as in
the petroleum region of western Pennsylvania, where it has long been
utilized in generating steam for drilling oil wells.

In 1826 the _American Journal of Science_ contained a letter from Dr.
S.P. Hildreth, who, in writing of the products of the Muskingum (Ohio)
Valley, said: "They have sunk two wells, which are now more than four
hundred feet in depth; one of them affords a very strong and pure
salt water, but not in great quantity; the other discharges such vast
quantities of petroleum, or, as it is vulgarly called, 'Seneka oil,' and
besides is so subject to such tremendous explosions of gas, as to force
out all the water and afford nothing but gas for several days, that they
make little or no salt."

The value of the foregoing references is to be found in the testimony
they offer as to the duration of the supply of natural gas. Whether we
look to the eternal flaming fissures of the Caucasus, or to New York,
Pennsylvania, and Ohio, there is much to encourage the belief that the
flow of natural gas may be, like the production of petroleum, increased
rather than diminished by the draughts made upon it. Petroleum, instead
of diminishing in quantity by the millions of barrels drawn from western
Pennsylvania in the last quarter of a century, seems to increase,
greater wells being known in 1884 than in any previous year, and prices
having fallen from two dollars per bottle for "Seneka oil" to sixty
cents per barrel for the same article under the name of crude petroleum.
Hence we may assume that, as new pipe-lines are laid, the supply of
natural gas available for use in the great manufacturing district of
Pittsburg and vicinity will be increased, and the price of this fuel