This is the second stop on my Kew Gardens tour. The rainforest conservatory.
‘Heating was an important element of the glasshouse’s design, as tropical palms need a warm, moist environment to thrive.
Originally, basement boilers sent heat into the glasshouse via water pipes running beneath iron gratings in the floor. A tunnel ran between the Palm House and the Italianate Campanile smoke stack that stands beside Victoria Gate. This 150-metres-long (490 ft) passage served the dual purpose of carrying away sooty fumes to be released from the chimney and enabling coal to be brought to the boilers by underground railway.
Today, the glasshouse is heated using gas and the tunnel houses Palm House Keeper Wesley Shaw’s office.’