The story of the quest to find a way of calculating longitude at sea is well known, thanks largely to Dava Sobel’s excellent book Longitude. John Harrison was responsible for the eventual solution, by constructing a clock of unprecedented accuracy. He devoted forty-three years of his life to marine chronometers, battling against both the numerous engineering problems to be overcome, and the resistance of the scientific establishment of his day. His first marine chronometer (H1), produced in 1737, was a mass of whirling rods and springs that weighed seventy five pounds, and required a four foot square case to house it. His final chronometer (H5) resembled a large pocket watch, weighed three p
In 1853 most of the world’s warships were still made from wood and powered by sail. The ships of the line that had dominated the great sea battles of the Napoleonic Wars continued to rule supreme in the navies of the world. In the decades after the fall of Napoleon there had been few major fleet actions between modern navies to spur innovation, and with no immediate prospect of battle, there seemed little need for development in warship design. But all that was about to change in a sea battle fought on the southern shore of the Black Sea. Developments in warship design might have slowed to a snail’s pace, but the same could not be said of naval guns. In the 1820s the French artillery General
Portsmouth is on England’s southern coast and has long been the home of the Royal Navy. Known by the nickname Pompey, its special geography marked it out from the earliest times as an ideal location for shipping. The city is on an island, divided from the mainland by a saltwater creek, which gives it excellent natural defences. To the west of this island is a huge harbour capable of sheltering the largest of fleets. The entrance is only two hundred metres wide, which makes it both easy to defend and ensures that the pent up tide flooding through it keeps the channel free from obstruction. All of this within eighty miles of London. Few more suitable places to base a fleet could be conceived.
