Nice one Joan
Yes it's a clog maker's stock knife. This single tool is used to carve the "stock" or last out of wood. The leather uppers are then nailed on.
Clogs became popular in Lancashire because of the weaving of cotton, which has to be kept permanently wet to stop it breaking during the weaving process. Consequenly it was very wet in weaving sheds and the clogs kept you out of the water.
Well done Joan