With what may we insulate [hot food], and with what may we not insulate [them]? We may not insulate [them] neither with marc, nor with manure, nor with salt, nor with lime, nor with sand, either wet or dry; nor with straw, nor with grape skins, nor with flocking, nor with grasses, when they are moist, but we may insulate [hot food] with them when they are dry. We may insulate [hot food] with clothing, with produce, with pigeon feathers, with carpenters’ sawdust, or with fine flax combings. R’ Yehudah prohibits fine [combings] but permits coarse [combings].