[click the photos to enlarge]
The loom used for weaving wool. A four-shaft floor loom. Very primitive with re-bars on top to hang the pulleys from. Quite a change from back strap looms with fine and dense warp threads. The wool warp and weft threads were not so fine or dense.
A close up of the wool loom that shows how primitive the mechanism is to hold tension on the warp beam. Re-bar again. Making a ratchet is difficult and many other solutions to keeping warp tension exist.