Twenty-three men in work garments pose for the camera in a caisson chamber. The space is illuminated by a light hanging from the ceiling. Their surroundings are made of wood, and slabs of rock and concrete. Objects seen in the photograph are shovels, a wooden crate, and a metal chain. Most of the workers wear long-sleeved, thermal shirts with suspenders. Eleven of the men wear hats, and two wear thigh-high, possibly rubber, boots.