This is a very early English sea chart of the island of Chusan and area, now known as the Zhoushan Archipelago. It is from the extremely rare and very important ‘English Pilot. The Third Book Defcribing the Sea-Coafts, Capes, Headlands, Streights, Soundings, Sands, Shoals, Rocks, and Dangers …’, first published in London, 1703. The region is located on the East China Sea just south of the Yangtze River delta. This is a region of major interest to the early European traders with China. The English Factory is marked on the island which was the main hub for British activity in the area. Nearby was access to the strategically important Grand Canal construction of which began in the fifth century B.C. For a long time it was the oldest and longest man-made waterway in the world. It allowed barges to travel the large distance to Beijing. The map is further embellished with rhumb lines that radiate and the north is to the right.

In 1671 John Seller (fl.1664-97) began work on the ‘English Pilot’, a multi-volume work that was intended to challenge the Dutch monopoly in sea atlases. Seller produced an incomplete ‘Oriental navigation’ in 1675. Soon after he was in financial trouble and unable to complete the project Seller sold his rights to John Thornton (1641-1708), the Official Hydrographer to the English East India Company. Thornton published the first edition of the ‘Third Book’ in 1703. While many authorities believe Thornton largely based his charts on those of earlier Dutch cartographers, those of China often utilised East India Company material. The ‘English Pilot’ proved to be a commercial success. John Thornton died in 1708 and his son Samuel took over the business. The atlas no doubt contributed in the future English dominance in publishing sea charts. NMM 426; Shirley (2004) Atlases in the British Library M.Thor 3a no. 35; Verner ‘Notes to Facsimile edition of the English Pilot Third Part 1703’.