Hi
The combined hammer/spade/billhook was often sold as a Gamekeepers Friend in the Victorian Edge Tool Catalogues of most of the Sheffield makers.... Sadly I have never seen one in the 'flesh' but would be interested in any other images of these or similar tools for my archives....
More common was the combined billhook hammer - common being a relative term as these are also like hen's teeth, I have only seen three or four in thirty years of edge tool collecting, and just managed to buy one (at an exhorbitant price)....
For more info on billhooks see: www.billhooks.co.uk