[Regarding] a ball or a coil of reed-grass that were placed over the mouth of a barrel: If one plastered the sides, it has not protected [the uten- sil] until he plasters above them and below them, and the same is true for a woven cloth. [If the cover] was of papyrus or of leather and one tied it with a cord, [then] if one plastered the sides, it has protected [the utensil].

[Regarding] a barrel that peeled and its pitch remains intact, and similarly containers of fish brine sealed with gypsum at the rim: R’ Yehudah says: They do not protect; but the Sages say: They protect.

[If] a barrel developed a hole and the sediments blocked it, they have protected it. [If] one plugged [the hole] with a vine, [it does not protect] until one plasters the sides. [If] there were two [vines], [they do not protect] until one plasters the sides and between one vine and the other. [Regarding] a board that was placed over the mouth of an oven: If one plastered the sides, it protects. [If] there were two [boards], [they do not protect] until one plasters the sides and between one board and the other. [If] one joined them with sinim or with shugmin, one need not apply plaster in the middle.

An old oven was within a new [oven] and there was a sereedah over the mouth of the old [oven]: [If] the old [oven] is removed and the sereedah would fall, [then] everything is tamei, but if not, everything is tahor. A new [oven] was within an old [oven] and there was a sereedah over the mouth of the old [oven]: If there is less than a handbreadth between the new [oven] and the sereedah, [then] everything within the new [oven] is tahor.