HOW THE HOLE WAS MADE AND THE OIL BROUGHT UP.


A letter from Bradford, Pa., says: The machinery used in boring one of
these deep oil wells, while simple enough in itself, requires nice
adjustment and skill in operating. First comes the derrick, sixty feet
high, crowned by a massive pulley.

The derrick is a most essential part of the mechanism, and its shape
and height are needed in handling the long rods, piping, casting, and
other fittings which have to be inserted perpendicularly. The borer or
drill used is not much different from the ordinary hand arm of the
stone cutters, and the blade is exactly the same, but is of massive
size, three or four inches across, about four feet long, and weighing
100 or 200 pounds. A long solid rod, some thirty feet long, three
inches in diameter, and called the "stem," is screwed on the drill.
This stem weighs almost a ton, and its weight is the hammer relied on
for driving the drill through dirt and rock. Next come the "jars," two
long loose links of hardened iron playing along each other about a
foot.

The object of the jars is to raise the drill with a shock, so as to
detach it when so tightly fixed that a steady pull would break the
machinery. The upper part of the two jars is solidly welded to another
long rod called the sinker bar, to the upper end of which, in turn, is
attached the rope leading up to the derrick pulley, and thence to a
stationary steam engine. In boring, the stem and drill are raised a
foot or two, dropped, then raised with a shock by the jars, and the
operation repeated.