Liwei's tan fingers grazed the smooth, metallic wall of the industrial-sized vent. The pads of his left digits scraped stray weld scours, left irresponsibly unsanded as the construction of the facility moved forward. As his hand dragged along the encasement, he felt subtle ridges and grooves like the surface of some flat rock, solid and even at first glance but quickly settling to the startling appearance of nooks and crevices in the face of the shape. Liwei regarded this with little confidence as his glistening gaze migrated to the shape of the shaft - evidently about six feet in height and three in width. The shaft was barely lit but by the distant glow of the aforementioned grate, illuminating a small area before it receded into rough and fiercely welded shadows.