Stairwell Echo

The hallway acoustics had died down, but the heavy metal fire door at the corridor's far end was humming with cold drafts. I marched straight to the threshold. At the base sat a heavy cast-iron doorstop wedge, half-jammed under the steel frame. I didn't step over it. I planted both boots into the rough linoleum, leaned my shoulder into the iron wedge, and drove my full weight forward. It ground against the concrete with a fierce, hollow screech. The door shuddered open a couple of inches, unleashing the cavernous reverb of the multi-level concrete stairwell. Cold wind roared up from the abyss. The outpost is secure, and the acoustics are dialed in.