ID: 4158
Date: Unknown
Donated By:
Description: Underground Sites No 1 bccm
Two "banks" of steam boilers for the power house steam engines. Bottom left of picture shows an automatic "chain grate", which was under each "bank". The "chain grates" slowly carried burning coal under the boilers to heat them, and create steam. The burnt coal ash then dropped off the moving grate, at the back of the boilers.