Lapis Gabinus slab originally used as part of a drainage channel along with Lapis Gabinus slabs 8404, 8399, 8407, 8358, and 8357. This slab, along with 8358 prove that there were two different drainage features, likely at two different periods in this space. 8358, and 8400 prove that this drainage feature was linear running north to south and did not turn to connect with cut 8292 for a fistula. It is likely that 8292 was installed after the drain associated with 8358 and 8400 went out of use.