The next day I returned to the site with Timothy, and we set about completing the columns and filling the inerior space. Unfortunately, it began to rain, heavily at times, which caused the mortar to be continually diluted and run and made it very difficult to place the stones as precisely as we wanted. However, neither the interior stones, nor the columns themselves, for that matter, have any structural function--the arch was rock solid, so the messy mortar was only an esthetic problem. Nevertheless, we managed to fill up all our spaces and set the top slab in place and cover everything with a tarp before heading home.