abor, or to better the quality of printing, the ultimate
aim has always been the same. It has been the constant incentive to
invention and the standard for judging the adaptability of a press.

The first printing press was the "wooden screw" press, which came into
use about the middle of the fifteenth century, and was built upon the
same mechanical principle as the linen presses in the homes of the
well-to-do. This was the press used by Gutenberg.

It consisted of two upright timbers held together at the top and the
bottom by crosspieces of wood and with two intermediate cross-timbers.
One of these intermediate cross-timbers supported a wooden or stone
"bed" on which the form of type was placed, and through the other
passed a large wooden screw, the lower point of which was attached to
the centre of a flat, wooden plate, called the "platen." The lower
side of the platen was covered with a soft "packing" or "blanket" of
cloth. After the type had been inked, a sheet of paper was laid on it.
This paper had previously been dampened so that it would take a better
impression of the type. The screw was then turned down until the
platen pressed the paper against the inked type, and produced a
printed sheet.

The form of type was incased in a frame called a "coffin." These
coffins and the type within them were very heavy, but they had to be
lifted in and out of the press by hand. After each impression the
platen was screwed upward so that the sheet of paper which had been
printed could be removed and hung up to dry.

This simple form of press continued in use without material change
until the early part of the seventeenth century. The first
improvements on it came about 1620, and consisted of a device for
rolling in and out the wooden or stone bed on which the type rested
instead of lifting it by hand, of a new form of iron hand-lever for
turning the screw, and of an iron screw in place of the wooden one.
These were the inventions of William Janson Blaeuw, a printer of
Amsterdam. Blaeuw's press was introduced into England and used there
as well as on the continent. It was substantially the same press as
that on which Benjamin Franklin worked when in London in 1735.

After this first type of printing press had been in use for three and
a half centuries, a much-improved form was invented by the Earl of
Stanhope in 1798. The frame of his press was made of iron, cast in one
piece; the bed, the impression plate, or "platen," and