According to my dad ...an ex docker....and from Clarence Grove....Garston is the last Dock on the South Side of the Mersey in Liverpool and the river used to silt up.....occassionaly ships would get stuck in the mud....men would wait until the tide went out and dig out the mud surrounding the ship...when the tide came back in , the boat would be freed....of course there are MANY Garston people who say the term Mudman is totally fabricated....I have a friend who says my dads explanation is totally tripe....we have Dredgers now to clear the mud, but before Dredgers it was cleared by hand....I believe my dad....allan