> Why is it a chimney, here, please?

Thanks for the reply on this wwh - spot on.

Y'all may like to know that climbing has also spawned 'chimney' - the verb - ("We'll have to chimney that section of the climb"). This style of ascent or descent is where the climber braces their back against one wall of the chimney and locks their legs against the opposite wall - movement being afforded by little shuffling steps up or down. Hence 'chimneyed' and 'chimneying' as well ("Joe took the lead while we were chimneying that section").

stales