Hammersley, the Duke of Atholl's London agent at the time of the Revestment.

He was the man the Manx merchants went to when they realised what was being negotiated. Hugh Cosnahan and a fellow examinant travelled to London on the merchants' business, taking John Christian, then a merchant in Douglas, to assist in mercantile matters. Being already acquainted with Hammersley as the Duke's agent, they waited on him as soon as they arrived to learn what was doing or had been done respecting the affairs of the Isle of Man, and told him they thought the inhabitants extremely ill used by the Duke in not having been timely acquainted with the treaty carried on between the Government and his Grace. Hammersley was surprised that they had not been told. He said that Mr Quayle had directions from the Duke to apprise the inhabitants of what was going forward respecting the sale of the Island, and turning to Quayle he put it to him directly that he had been given those directions.

The failure became part of the Manx case afterwards. One account of the transactions holds that the Atholl family was itself in total ignorance of its rights in the Island, and that Quayle, for private reasons of his own, neglected to inform the people of the negotiation then pending although ordered to do so both by his employer the Duke and by Hammersley as his agent. On that reading the bargain was forced on the Atholl family while they were ignorant of what they were parting with, and the Crown bought a great deal more than it had asked for.

He handled the ordinary money as well. Governor Cochrane reported in February 1758 that the clergy were waiting for an answer from Mr Hammersley before they could divide their money.