By a series
of operations it is now heated and drawn out longer and longer, while
its thickness diminishes and its diameter grows less. These operations
are carried out by means of a number of hydraulic rams, which
regularly decrease in size. Fig. 3 roughly represents one of these
rams with the plunger ready to descend and force its way into the
partially formed red hot gas cylinder, C, and further into the well,
W. The plunger may be compared to a finger and the cylinder to a
glove, while the well may represent a hole into which both are thrust
in order to reduce the thickness of the glove. With huge tongs the
cylinder, fresh from the furnace, is placed in position, but just
before the plunger presses into the red hot cup, one of the workmen
empties into the latter a little water, so as to partially cool the
bottom and prevent its being thrust out by the powerful plunger. Oil
is also used plentifully, so that as the plunger works slowly down the
red hot mass, it is surrounded by smoky flames. It presently forces
the cylinder into the well, and when the end of the stroke is reached,
a stop piece is inserted through an opening in the upper part of the
well, so as to arrest the edge of the cylinder while the reverse
action of drawing out the plunger is proceeded with.
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