Chapter 1, Mishnas 7, 8
Maximum size of an enclosure for Shabbos carrying depends on how many people join to create it. May be invalidated if it includes too large an unused area. What if one of them dies during Shabbos? A military camp receives six leniencies, inlcuding exemption from creating an eiruv and washing before eating a meal, but they must wash after the meal for their own protection from Sodomite salt. They must also be buried where they fall, lest they become an unattended corpse.