In message , Rod Speed
writes


"Ian Jackson" wrote in message
...



I was alarmed to find that the 'mineshaft' was almost full to the
brim with fine sand - which presumably had been transported there by
ants.

Unlikely.

So how did it get there? It certainly wasn't there when we moved here.
BTW, the soil is essentially heavy clay and flint - but when the ants
make a nest in the lawns, the create a small erupting 'volcano' of fine
sand at the entrance hole.


--
Ian