Vice Admiral Sir Henry Mangles Denham (28 August 1800 – 3 July 1887) was a Royal Navy officer who went on to be Commander-in-Chief, Pacific Station. Early career Denham entered the navy in 1809. He served on from 1810 to 1814, initially under Captain Martin White, engaged in survey work in the Channel Islands. He became midshipman while serving on Vulture. He continued to work on the Channel Islands survey until 1817, again under White. In 1817, White took command of the survey vessel and Denhham worked under him on surveys in the English Channel and Ireland. He was promoted to lieutenant in 1822. From October 1827, he was lieutenant-commander in , surveying the coast of France. From September 1828 to March 1835, he surveyed the Bristol Channel, and the ports of Liverpool and Milford. In the early 1830s the expansion of the Port of Liverpool was being severely restricted by the silting of the channels leading to the port. The Dock Trustees asked the Admiralty for help, and in 1833 Denham was assigned to survey the area. He carried out the most thorough survey of the Mersey and its approaches to date, and analysed the volumes and patterns of flow and the quantities of solid material transported by each tide. He argued that if existing channels were becoming blocked the tidal flow must be going somewhere else. He was able to identify and chart a new channel, and mark it with buoys. This greatly increased the volume of shipping the port could handle. He was awarded the Freedom of the Borough of Liverpool in 1834, and in 1835 became Resident Marine Surveyor to the port. In 1837, when shoaling became problematic on the outer part of the channel, he introduced a system for dredging with a steamer towing a set of spiked cables spaced along an oak beam. This continued in use until 1890. On 28 February 1839 he became a Fellow of the Royal Society. According to Mountfield (1953) "it was Denham's work during the 'thirties and 'forties which made Liverpool the great terminal port which the rapidly swelling trade of industrial England so urgently required." Denham's time at Liverpool ended in discord, with Denham frustrated at the lack of resources available. This came to a head in the great storm of 1839 when lightships as well as buoys were torn from there moorings, and Denham saw himself