There is a well on this mount which was in former days named “Giant’s” Well, on account of the giant Cormelian, or Cormoran, who inhabited the spot. The well, or cistern, is excavated in the rock; it is still in existence, but is now known by the title of “Jack the Giant Killer’s Well,” and is fairly well lined with pins thrown there by persons desirous of procuring their wishes. The conclusion to be drawn is that the clever youth “Jack,” who by stratagem ridded the mount of its monster by killing the giant Cormoran, was honoured by the change of the well’s designation as a recognition of his service.
From ‘Ancient and Holy Wells of Cornwall’ by M and L Quiller-Couch (1894).