Eighteen Treatises from the Mishna, by D. A. Sola and M. J. Raphall, [1843], at sacred-texts.com
§ 1. Wherein may hot vessels [saucepans] be deposited [to retain
the heat]? And wherein may they not [be] deposit[ed]? They must not [be] deposit[ed] in olive- kernels, in dung, in salt, in lime, or in sand (whether wet or dry), nor yet in straw, nor in grape-husks, nor in woolflocks, nor in herbs, while these are wet; but it is permitted to deposit in them should they be dry. It is permitted to deposit [the vessels or saucepans] under garments or under fruits [any kind of grain, &c.], under pigeon-feathers, or shavings, or under fine flaxen tow; R. Jehudah prohibits fine, but permits coarse [flaxen tow].
§ 2. They may [be] deposit[ed, wrapped] in skins, and removed [taken out of them again: likewise] in shorn-wool, but must not be removed [taken out] therefrom. How then is man to do? He takes off the lid [of the vessel or saucepan] and the wool falls off. R. Eleazar ben Azariah saith, "He inclines the vessel to one side, and takes out [what he requires], lest [were he to remove it] he cannot put it back again." 1 But the sages hold [that it is permitted to] take [the vessel] out, and [to] put [it] back again. If man has not covered up [his vessel or pot] while yet day [before the Sabbath comes in], he must not cover it after dusk; if he have covered it, and it is become uncovered, he is permitted to cover it again. He may fill a pitcher, and place it under a pillow or bolster [to take the chill off.]
43:1 As the tow or wool falling together, would fill up the cavity made by the saucepan; and it is unlawful to make another.