English: Lantau Island as surveyed in 1815. It is extracted from 1840 Ross Map or Chart of Hong Kong, which was a rare and remarkable nautical chart of the utmost significance. This 1840 maritime map of Hong Kong and vicinity is attributed to Captain Daniel Ross, Bombay Marine. During the first Opium War (1839 – 1842), this was the finest and most detailed chart of Hong Kong available. It predates the formal seizure of Hong Kong by Commodore Bremmer in 1841 and Belcher's subsequent 1843 chart by several years. It can only have been this chart, as well as by Belcher's yet unpublished 1841 manuscripts, that were used to negotiate the 1842 Treaty of Nanking, that formally ended the first Opium War and ceded Hong Kong to the British.

This map is derived from Daniel Ross's 1807 - 1816 survey of the China Coast on behalf of the British East India Company. Ross's survey work and his manuscript chart (possibly National Library of Australia, MAP RM 1590), was largely forgotten until the First Opium War (1839 - 1842), when his work was resurrected to serve as the basis for this updated March of 1840 chart. The updates over Ross's 1815 survey, which include additional soundings and other details, were most likely are based upon the surveys of I. A. Douglas, in 1839, at the outset of the First Opium War.

This is one of a three chart Admiralty hydrographic office series identified as 'China South Coast.' The present chart, first published in March, 1840, was the first of the series, with additional charts of surrounding waters, following in April and May. It covers the China coast from Macao to Hong Kong, with countless depth soundings and numerous fascinating annotations. The map identifies 'Chinese Tombs,' 'Pirate Harbor,' a 'Junk Town,' and provides a wealth of other information.