Ruel-bone

RUEL-BONE Is mentioned by Chaucer, and in the following passage, as the material of a saddle. It is not, of course, to be thence supposed that ruel-bone was commonly or even actually used for that purpose,[…]

White it glimmered, and the sea shimmered with star-mirrors in a silver net; cliffs of stone pale as ruel-bone in the moon-foam were gleaming wet.