heddle

niisi A component in a loom, being one of a number of similar components, through the eye of each of which a distinct strand of the warp is threaded.
1808, John Duncan, Practical and Descriptive Essays on the Art of Weaving, Volume 1, http://books.google.com.au/books?id=IyBSAAAAYAAJ&pg=PA72&dq=%22heddle%22%7C%22heddles%22&hl=en&sa=X&ei=K580Uf7MOeuYmQXK_4GwBg&redir_esc=y page 72,

The only other table, generally used by operative weavers, is that for setting the heddles, so as to correspond with the reed. Few weavers are in possession of a sufficient variety of heddles, to suit every reed in which they may be employed to weave cloth.

The heddles and heddle frames, Fig. 3, and the reed may be purchased from dealers in craftwork supplies.

If errors have occurred in threading the heddles, it is usually expedient to remove all threads from the begining(si) of the error and re-thread them correctly.

After each frame has been heddled, stand upright within easy reach until the full set has been completed.

This, of course, discounts the idea that the system of heddling based on Icelandic descriptions (Hoffmann, 1964, 188, fig. 91) has been used for all time, although it could in theory have been used for any of the 2/2 twills in the York collection.

After heddling she takes the reeds and arranges them as ordered. She knows that if reed denting is uneven, the textile is ruined.