e different coils. These loose rolls, of
course, occupied much space and could be put into the tar only in a
standing position, because in a horizontal one the several coils would
have pressed together again. The loose roll was therefore slipped over
a vertical iron rod fastened into a circular perforated wooden foot.
The upper end of this iron rod ended in a ring, in which the hook of a
chain or rope could be fastened. With the aid of a windlass the roll
was raised or lowered. When placed in the pan with boiling tar, it was
left there until thoroughly saturated. It was then taken out, placed
upon a table, and the excess of tar allowed to drip off into a vessel
underneath. After partially drying, the roll was spread out in open
air, occasionally turned, until sufficiently dried, when it was rolled
up again.
In order to neutralize the smeary, sticky condition of the surface and
avoid the disagreeable drying in open air, the experiment of strewing
sand on the sticky places was tried next. The weight of the paper was
largely increased by the sand, and appeared considerably thicker. For
this reason the method of sanding the paper was at once universally
adopted. To dispense with the process of permitting the surplus tar to
drip off, means were devised by which it was taken off by scrapers, or
by pressing through rollers. The scrapers, two sharp edged rods
fastened across the pan, were then so placed that the paper was drawn
through them. The excess of tar adhering to its surface was thereby
scraped off and ran back into the pan.
This work, however, was performed better and to more satisfaction by a
pair of rollers fastened to the pan. These performed a double duty;
thoroughly removed the tar from the surface and by reason of their
pressure they caused a more perfect incorporation of the tar with the
fibers of the paper. Finally, different factories employed different
methods of manufacture, one of which was to cut the rolls into
definite lengths of about ten yards; these were then rerolled very
loosely and immersed in the hot tar until sufficiently saturated. The
paper was then passed through the roller, much pressure exerted, and
then loosely rolled up again. Being tarred once, it was then laid into
a second pan with hot tar, reeled out after a time, strewn with sand,
and rolled up again. Another method was to cut clothes lines into
lengths of about fifteen yards, and at a distance of two inches have
knots tied in them
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