exaggerated idea of the pressure to be exercised, and at intervals of 50
to 100 feet he set up air chambers 10 inches in diameter. The weak point
in this line, however, proved to be the joints; the pipes were of cast
iron, and the joint-leakage was so great that little, if any, oil ever
reached the end of the line, and the scheme was abandoned in despair.

In connection with this question of oil transportation, a sketch of the
various methods, other than pipelines, adopted in Pennsylvania may not
be out of place. We are mainly indebted to Mr. S.F. Peckham, in his
article on "Petroleum and its Products" in the U. S. Census Report of
1880, for the information relating to tank-cars immediately following:

Originally the oil was carried in 40 and 42 gallon barrels, made of oak
and hooped with iron; early in 1866, or possibly in 1865, tank-cars
were introduced. These were at first ordinary flat-cars upon which were
placed two wooden tanks, shaped like tubs, each holding about 2,000
gallons.

On the rivers, bulk barges were also, after a time, introduced on the
Ohio and Allegheny; at first these were rude affairs, and often of
inadequate strength; but as now built they are 130 x 22 x 16 feet, in
their general dimensions, and divided into eight compartments, with
water-tight bulkheads; they hold about 2,200 barrels.

In 1871 iron-tank cars superseded those of wood, with tanks of varying
sizes, ranging from 3,856 to 5,000 gallons each. These tanks were
cylinders, 24 feet 6 inches long, and 66 inches in diameter, and weighed
about 4,500 lb. The heads are made of 5/46 in. flange iron, the bottom
of 1/2 in., and the upper half of the shell of 3/16 in. tank iron.