Editing Parchment (section)

== Manufacture ==
Parchment is prepared from pelt&nbsp;– i.e. wet, unhaired,<ref name="York-2017" /> and limed skin&nbsp;– by drying at ordinary temperatures under tension, most commonly on a wooden frame known as a stretching frame.{{sfn|Reed|1972|}}

===Skinning, soaking, and dehairing===
After a carcass is [[Skinning|skinned]], the hide is soaked in water for about a day. This removes blood and grime and prepares the skin for a dehairing liquor.<ref name='reed75'>{{harvnb|Reed|1975}}</ref> The dehairing liquor was originally made of rotted, or fermented, vegetable matter, like beer or other liquors, but by the [[Middle Ages]] a dehairing bath included [[lime (mineral)|lime]]. Today, the lime solution is occasionally sharpened by the use of sodium sulfide. The liquor bath would have been in wooden or stone vats and the hides stirred with a long wooden pole to avoid human contact with the [[alkaline]] solution. Sometimes the skins would stay in the dehairing bath for eight or more days depending how concentrated and how warm the solution was kept – dehairing could take up to twice as long in winter. The vat was stirred two or three times a day to ensure the solution's deep and uniform penetration. Replacing the lime water bath also sped the process up. However, if the skins were soaked in the liquor too long, they would be weakened and not able to stand the stretching required for parchment.<ref name='reed75' />

=== Stretching ===
After soaking in water to make the skins workable, the skins were placed on a stretching frame. A simple frame with nails would work well in stretching the pelts. The skins could be attached by wrapping small, smooth rocks in the skins with rope or leather strips. Both sides would be left open to the air so they could be scraped with a sharp, [[blade#Patterns of knife blades|semi-lunar knife]] to remove the last of the hair and get the skin to the right thickness. The skins, which were made almost entirely of [[collagen]], would form a natural glue while drying and once taken off the frame they would keep their form. The stretching aligned the fibres to be more nearly parallel to the surface.