Earl of Pembroke was purchased by the Admiralty in May 1768 for  and sailed to Deptford on the River Thames to be prepared for the voyage. Her hull was sheathed and caulked, and a third internal deck installed to provide cabins, a powder magazine and storerooms.
The Earl of Pembroke was acquired by the Admiralty in May 1768 and transported to Deptford on the River Thames to be outfitted for its journey. Its hull was covered and sealed, and a third internal deck added to accommodate cabins, a gunpowder magazine, and storage rooms.