Shabbat 82a and Shabbat 82b, finishing up issues of the eliminatory system, how to cleanse oneself safely, and how to help the smooth workings of the system, with a side point about how wisdom in that area counts as Torah as well. The last Mishnah, about the size of a clay shard to count as a minimal amount for Shabbat carrying, cites a verse as a sort of support, taking us to the next chapter, where R. Akiva uses verses to condition his understanding of how the Rabbis structured their decree of ritual impurity for items of worship of powers other than Gd.
