a new world for ironman part 2

The low hum from the metallic radiator pipe caught my attention across the floorboards. I walked over and examined the joint where the painted iron meets the valve assembly. Bending forward, I placed my right palm flat against the cold cylindrical metal to measure the vibration frequency. The pulse was rhythmic and steady. Using the flat edge of a discarded metal paperclip I found on the floor, I tapped lightly against the lower pipe flange. The resonant ping confirmed the pipe is hollow and structural integrity is solid. A viable conduit for acoustic mapping.