After receiving information from Francis Vickerman via John Lloyd, that possible suspects in the assassination of William Horsfall had been at the house and workshop of the master cropper, Joseph Mellor, on Saturday 10th October 1812, the magistrate Joseph Radcliffe first acted to summon and question one of Mellor's apprentices, a boy called Joseph Oldham.
Oldham told Radcliffe that on the day Horsfall was shot, another apprentice called Thomas Durrance showed him 2 pistols brought to the house by 2 men that evening. Later on, a man he did not know called upon the house to ask if he could wash himself, accompanied by another man, called George Mellor - a cropper and his master's cousin. Oldham said that Mellor had walked about the workshop while the other man washed himself. He described the unknown man as stout and tall, with light-coloured hair, wearing a dark or drab-coloured coat, but with no marks of blood upon him. He said that George Mellor also wore a drab-coloured coat.
After the vague description that Vickerman had given Lloyd of the suspects, he now had a definite name: George Mellor.
Joseph Oldham's deposition can be found at HO 42/129.