[Regarding] a sereedah that is placed on the mouth of an oven and sinks into it and it has no rim, [if] a sheretz is in [the sereedah], the oven is tamei. [If] a sheretz is in the oven, food that is in [the sereedah] is tamei. For only utensils protect from [the tumah of] an earthen- ware utensil. [Regarding] a barrel that is full of tahor beverages and is placed beneath the floor of an oven, [if] a sheretz is in the oven, the barrel and the beverage are tahor. [If the barrel] was inverted and its mouth [opened] to the airspace of the oven, [if] a sheretz is in the oven, beverage sufficient to moisten that is on the bottom of the barrel is tahor.