"John Armstrong" wrote in message
...
On Fri, 29 Aug 2003 20:17:30 +0100, Jo
wrote:

My early victorian building has a nice stone facade covering what
looks like a messy mix of mortar and rubble.

What sort of stone is it? My house is uncoursed random limestone, 2
foot thick, and one problem with using a core drill as suggested is
that although the inner and outer faces of the wall are firmly
mortared in place, the middle of the wall is loose rubble fill. I can
see this loose fill causing problems for any drill.

Good point - rubble fill walls are a nightmare when encountered in these
circumstances. Fortunately they aren't too common.