Kevin Olson - Thanks Kevin. I just checked and the first hardy hole is 1,1/2 inch. The second hardy hole is 1, 1/4 inch.
ThomasPowers - Thank you for your response Thomas. It does seem difficult to pin down historical details on this particular anvil, well at least for me! I had searched for some time for information on this particular anvil form, going on the assumption (rightly or wrongly) that it might be a Peter Wright. But I became completely stumped. Naturally, this only served to further stoke my curiousity of course! It is certainly intriguing me.