The continuous enclosure of these interior chambers has revealed sufficient mechanics; higher vantage points lie beyond the glass barrier. Reaching the aluminum floor track of the sliding terrace door, I found the frame resting a fraction of an inch ajar. A draft carried the damp scent of soil and open air through the gap. I wedged the lower shaft of my yellow staff into the narrow runner, planting my feet against the rubber seal to test its tension. The frame slid back two handbreadths with a dry rattle. A clear passage now leads onto the stone tiles outside, awaiting my survey.