Early producers of this material would use wires to create brands called watermarks.  
In the Middle Ages, the most basic operation to make this good had a vatman handing materials back and forth to a coucher.  An eight-fold increase in the efficiency of producing this material was achieved through the use of the Hollander beater.  The Maya made this stuff from amate.  The Kraft process for making this good largely did away with the need for (*) rag men.  Until the 19th century, Europeans wrongly believed that the Arabic variety of this substance was made from cotton.  The Italian "milk mountains" got their name from the large amount of this material made in Amalfi.  Hand-made varieties of this material have a deckle edge.  This 3rd of the Great Inventions allegedly spread to the Islamic world thanks to Chinese prisoners obtained from the Battle of Talas.  Early producers of this material would use wires to create brands called watermarks.  For 10 points, name this writing material now largely made from trees.
In the Middle Ages, the most basic operation to make this good had a vatman handing materials back and forth to a coucher.  
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