yes sorry about the repeat thread--my mistake.
Thanks Barney for the quick reply!
not wishing to seem ungrateful for the help, but yes have read this also in 'the book', however, getting into a bit more detail;
The discussion is that a lower adit, as you say is to a shaft up to the main adit / chamber. However, this adit entrance down at the roadside is a long way away and much below than the chamber, and would represent a vast effort it would seem in the context of the whole small workings ( but would make sense for transportation. Anway, I guess it needs investigating!
thanks again for the input