Editing Duplicating machines (section)

==Letter copying presses==

[[File:Thinktank Birmingham - object 1951S00088.00001(1).jpg|thumb|A James Watt & Co. copying press, in [[Thinktank, Birmingham Science Museum]]. ]]

[[File:Kopierpresse.jpg|thumb|Iron letter copying press, late 19th century, Germany]]
In 1780 [[James Watt]] obtained a patent for letter copying presses, which [[James Watt#Copying machine|James Watt & Co.]] produced beginning in that year. Letter copying presses were used by the early 1780s by the likes of [[Benjamin Franklin]], [[George Washington]], [[Henry Cavendish]], and [[Thomas Jefferson]].<ref>{{cite web|author=Thomas Jefferson Encyclopedia|url=https://www.monticello.org/site/research-and-collections/polygraph|title=Copying Press|location=[[Charlottesville, Virginia]]|publisher=[[Thomas Jefferson|Th: Jefferson]] [[Monticello]]|accessdate=May 10, 2020|archive-date=July 27, 2019|archive-url=https://web.archive.org/web/20190727160141/https://www.monticello.org/site/research-and-collections/polygraph|url-status=live}}</ref> In 1785, Jefferson was using both stationary and portable presses made by James Watt & Co.

Using letter copying presses, copies could be made up to twenty-four hours after a letter was written, though copies made within a few hours were best. A copying clerk would begin by counting the number of master letters to be written during the next few hours and by preparing the copying book. Suppose the clerk wanted to copy 20 one-page letters. In that case, he would insert a sheet of oiled paper into the copying book in front of the first tissue on which he wanted to make a copy of a letter. He would then turn 20 sheets of tissue paper and insert a second oiled paper. To dampen the tissue paper, the clerk used a brush or copying paper damper. The damper had a reservoir for water that wet a cloth, and the clerk wiped the cloth over the tissues on which copies were to be made. As an alternative method of dampening the tissue paper, in 1860 Cutter, Tower & Co., Boston, advertised Lynch's patent paper moistener.

Then letters were written with special copying ink which was not blotted.  The copying clerk arranged the portion of the letter book to be used in the following sequence starting from the front: a sheet of oiled paper, then a sheet of letter book tissue, then a letter placed face up against the back of the tissue on which the copy was to be made, then another oiled paper, etc.

Prior to the introduction of inks made with [[aniline dyes]] in 1856, the quality of copies made on letter copying presses was limited by the properties of the available copying inks. Some documents that were to be copied with copying presses were written with [[copying pencil]]s rather than copying ink. The cores of copying pencils, which appear to have been introduced in the 1870s, were made from a mixture of [[graphite]], [[clay]], and aniline dye.

By the late 1870s, an improved method for moistening pages in copying books had been invented, and by the late 1880s it had been widely adopted. Rather than using a brush or damper to wet the tissues, the clerk inserted a thin moist cloth or pad between each oil paper and the following tissue.

[[File:The Rapid Roller Damp-Leaf Copier in use.jpg|thumb|The Rapid Roller Damp-Leaf Copier in use]]In the late 1880s, adoption of improvements in office systems for filing unbound documents increased the demand for copying machines that made unbound copies of letters, as opposed to copies in bound books. In 1886, Schlicht & Field of Rochester, N.Y., introduced the Rapid Roller Damp-Leaf Copier, a roller copier, which used pressure supplied by rollers to copy letters onto a roll of dampened paper. After copies were pressed onto the paper, the paper entered the cabinet under the copier, where it dried on a large roller. An attachment was used to cut dried copies off the roll.

Copies could be made more quickly with a roller copier than with a letter copying press. It was claimed that nearly 100 papers could be copied in two minutes with a roller copier. Roller copiers competed with [[carbon paper]] technology. It was claimed that a roller copier could make a half dozen copies of a [[typewriter|typewritten]] letter if the letter was run through the copier several times. It could make a dozen copies if the letter was written with a pen and good copying ink.

The Process Letter Machine Co. of Muncie, Indiana, offered the New Rotary Copying Press, a loose-leaf copier, in 1902.  This machine was similar to roller copiers but copied onto loose-leaf paper.