At the end of the "save-all," where the
fibers are to leave the "wire" for the next stage of their journey,
suction-boxes are placed, provided with an air-pump to take up the
surplus water that has not yet found its way through the meshes. Between
these suction-boxes above the wire is a wire-covered roll which
impresses the newly formed sheet; this impression cylinder is called a
"dandy roll," and it is from this that the web receives the markings or
impressions that characterize different papers. All watermarks,
patterns, and designs which it is desired to have appear in the paper
are put upon this roll and here impressed upon the soft sheet, which is
clarified and left transparent at the point of contact. Thus the
impression is permanently fixed in the fiber, so that it can be seen at
any time by holding the sheet to the light. The power of suggestiveness
is a quality which is highly esteemed wherever it is found, and which
frequently furnishes a standard of judgment.
Judged by such a criterion, the impression cylinder, or "dandy roll,"
has an added value, for in all probability its operation suggested the
idea of printing from cylinders, as in our present web or perfecting
presses.
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