the total fiber
furnish, and this likewise applies to the loading and sizing agents. In
case sulphite or soda fiber was used, the commercial product in the dry
state was charged into the beating engine and disintegrated, after which
the hurd stock was added in the wet condition.
_Beating._--Beating is that operation concerning which the paper makers
often say "there is where the paper is really made," and although the
statement may not be literally true it contains a great deal of truth.
It is the operation whereby the fibers are separated from each other,
reduced to the proper lengths, and put in such a physical or chemical
condition that they felt properly and form into a satisfactory sheet. It
is probable that the quality of the sheet depends more upon the proper
beater action than upon any other single operation. The action consists
in drawing a water suspension of the fiber between two sets of rather
blunt knives, one set being located in the bottom of a circulating
trough and the other set on the periphery of a roll revolving just above
the former set of knives. It is during this operation that the loading
and sizing agents are incorporated and the whole furnish is tinted
either to produce a satisfactory white or the desired color.
The term "paper making," as used in this publication, means the
operation of forming the finished sheet of paper from stock which has
been furnished and prepared in the beater. In these tests a 30-inch
Fourdrinier machine of regular construction was used, a machine which
often is used for the production of paper for filling regular commercial
orders. The machine is designed to cause the water suspension of fibers
to flow on to a traveling wire cloth, whereby the water drains away.
More water is removed by passing the wet sheet through a series of press
rolls, after which the sheet is dried on steam-heated drums and passed
through polished iron rolls, which impart a finish to the sheet. A
Jordan refining machine was employed in conjunction with the machine to
improve further the quality of the fiber, and a pulp screen was used in
order to remove coarse and extraneous materials from the fiber.
=DESCRIPTION OF TESTS.=
The nature of each complete paper test and the dependence of each
operation on the others were such that it does not seem advisable to
submit the results of the seven tests in tabular form. The numerous
cooks, however, which furnished the pulp for the paper tests are
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