William Earle was 30 years old when he wrote this letter to the lady who two years later would become his wife. He was captain of the slave ship Chesterfield and had arrived in Old Calabar in the Bight of Biafra on 23 July 1751 after a two-month voyage from the Mersey. Like all ships’ captains, he never missed a chance to send letters home and he was now taking advantage of the imminent departure of another Liverpool slave ship, the Neptune, to write home to the owners of his ship and his girlfriend, glad to be able to report that he enjoyed ‘a perfect state of good health, thank God’ and that his slaving activities were going well, having ‘got more slaves than [I] did expect in the time.’ This was William's last voyage as a slave ship captain, though he was to be busily involved in the Liverpool slave trade as part-owner, investor, administrator and supplier of trade goods until his death in 1788.

The historian of Liverpool shipping is fortunate in that two, really excellent, computerised datasets containing valuable information on the port's shipping have been created by dedicated researchers. The first of these is called ‘Liverpool Trade and Shipping, 1744–1786’, based on the port's ship registration books [Plantation Registers] and contains all known overseas voyages of Liverpool registered ships between those dates. The information in the registers has been supplemented by relevant sources in the National Archives and by material from the surviving newspapers of Liverpool and Manchester and the general shipping paper, Lloyds List. The data includes, where known, the ship's place and date of construction, dimensions and armament, owners, masters, crew numbers, voyages and subsequent fate. The second database is the ‘Trans-Atlantic Slave Trade Database’, published by Emory University in 2009. This amazing compilation is the culmination of many decades of independent and collaborative research in several countries and contains information on almost 35,000 slaving voyages between Africa and the Americas.