Windlass and cathead of HMS Terror (top) and HMS Erebus (bottom),
From Chris Ware's "The Bomb Vessel: Shore Bombardment Ships of the Age of Sail".
As I mentioned in an earlier post, Erebus (launched 1826) had been built with many more iron components than had been used for Terror's construction a decade earlier. This difference is noticable in the case of the knees (shaded blue) which reinforce the windlass and cathead (shaded red).
Terror surely gained a good deal of additional iron reinforcement during her various refits but it seems reasonable that if a wooden component was still doing its job then it wouldn't have been replaced without good reason. For very sound reasons Parry had ruled that Arctic ships should be identically equipped but I think it would be stretching that doctrine too far to extend it to structural components such as these.
Just possibly these small details may play a role in restoring a name to this currently anonymous victim of the Franklin tragedy.