A bagpipe is impervious to midras [tumah]. [Regarding] a trough of pisonos, Beis Shammai say: [It is susceptible to] midras [tumah]. But Beis Hillel say: It is [only susceptible to becoming] tamei with corpse-tumah. [Regarding] a trough [with a capacity of] between two logs and nine kavs that cracked, [it is susceptible to becoming] tamei with midras [tumah]. [If] one left it in the rain and it swelled, it is [susceptible to becoming] tamei with corpse-tumah. [If he then placed it] in the east wind and it developed a crack, it is susceptible to midras [tumah]. This is a stringency [that applies] to the remnant of wooden utensils over the original [utensil]. And a stringency [that applies] to the remnants of wicker utensils over the original [utensil is] that originally they are not susceptible to tumah until their [rims are] secured. But after their [rims are] secured, even though their rims fell away, [if only] the smallest amount [of the rims remain] they are tamei.