The Ouachita telegraph. [volume] (Monroe, La.) 1865-1889, 1873-10-31

MONROE, La, oCTOBER 81. 1873.
HOW OIL WELLS ARE SUNK.
(From the Scientific American.l
The business OF drilling wells has
now fallen almost entirely into the
hands Of professional drilleEs. When a
man or a com6ip has decided upon a
we'll, and selected its site, the first step
is to put up d derrick, or, as 1t is term
ed, . sscafpenter,srig.'' This IS a frame
work, made mostly Of plank, from IS
to IS fest, high, about IA feet square at
the bottom and running nearly to q
point At the top, The cost of a derrick
Is about ee00., The tools used in drill
ing are the bit, which is like any ordi-
nary rock drill but larger, being about
three feet in length; above that is the
augef stem; then two chain links
called the +" jars" and above that the
sssinker bar" This is attached at the
upper end to the rope which passes
over q pulley at the toPiof the derrick,
and thence down to a7large windlass
outside Of the derrick. The drilling Is
done by 9 steam engine with crank
movement, which keeps the drill at
work day and night, a man standing
byin the derrick to give the tools more
rope at proper intervals, and to turn
the drill while IL cooperating. After
the drill has reduced certain quantity
of rock to sand, It is drawn from the
we'll up into the derrick, and the sand
pump is lowered and the sand is
brought out, when the drill is again in
serted. The rope used must be of the
very best quality, and in digging deep
wells 1t requires two ropes, as the sand
very soon cuts them out. The expense
is q very considerable one, being $500
for each rope. The tools for drilling
that are now used weigh 1900 pounds,
those that were first used weighing
only 80 pounds. A goad set of drillers
will put we'll down in about 65 work
and no accidents; but it oftentimes
takes six months to reach the oil sand.
The rock in which the oil is found
has very decided dip from the north
to the south, it being about 16 feet to
the mile. In the old or northern part,
it is found at q depth Of from four to
seven hundred feet deep, whereas the
new wells at Modoc are from fourteen
to seventeen hundred feet deep, the ex-
pense Of drilling one of the new wells
being nearly double that of one of the
old ones. The drillers generally know
where they are by the kind of sand
that they bring out.
At Modoc, at depth of about 500
feet, they strike what is called the
mountain sand rock, down to which
they bore an eight-inch hole. Here
they know that they are below oil fresh
water, and they put in casing, down
to and resting on that rock, with an in
side diameter of 81 inches. From there
they bore, through the casing, the re-
mainder Of the well with diameter Of
81 inches, depending upon this shoulder
of rock at the bottom of the casing to
shut Off the salt water, which Is some
times found in large quantities. The
next sand rock OF importance that is
found Is called the second sand, which
lies at depth Of a little over 1900 feet
and sometimes produces oil. This,
however, Is not considered n good sign,
and makes future drilling operations on
the same we'll rather gloomy work, rs
q first-class well cannot be expected
The ffty-foot sand rock comes next
the next is the powders then comes
the corn meal sand, so called because OF
its resemblance to corn meal. From
that you get to 10 feet of slate, and
then you strike the oil sand, which is a
sort OF pebbly rock aud II the well Is
going to amount to anything, oil APP
pears the moment you penetrate or
even scratch this rock. Between these
strata that have mentioned, the space
is filled up mostly with shells, slate,
soap rock, sand, ect', the drilling being
very easy. But in the sand rocks above
enumerated, slow time is made by the
drillers; and the mountain sand is so
hard that it wears the drill, and the
particles of steel from the bit are very
perceptible among the grains of sand.