adjoin it. Economy Agriculture Ham was an agricultural community for centuries, with meadow and pasture land mostly along the river, and common grazing. The tithe map of 1842 showed a total area of , but when adjusted for the land in Richmond Park, were arable, meadow or pasture, was common land, and only woodland. The crops were mainly wheat, barley and oats. with some flax, potatoes, turnips and mangel wurzels. Livestock included cows, sheep, pigs, goats, ducks and chickens as well as horses and donkeys – many of which grazed the common land. Ham had three farms at the time, all on land owned by the Earl of Dysart. Unusually, these remained very little enclosed and the open field system survived in use until the late 19th century. Improvement in transport and the growth of London led to a shift from general mixed agriculture to market gardening by the early 20th century. Ultimately, the same growth fuelled demand for housing land, and this factor along with the greater profitability of gravel extraction on land that could not be used for housing, meant that agriculture in Ham had ceased by the mid-1950s. Gravel In 1904 William Tollemache, 9th Earl of Dysart leased part of the farmland to the Ham River Grit Company Ltd to extract sand and ballast. A dock was constructed in 1913 and a lock in 1921, parts of which remain as the Thames Young Mariners water activity centre. A narrow-gauge railway linked the site to the main road. During the Second World War the flooded pits were reputed to have been used to store sections of the Mulberry harbour. After the war, most of the pits were filled with bomb-damage rubble from London. The pits operated until 1952, after which some of the land was used for subsequent housing development. Local resistance to further development led to the area being designated Metropolitan Open Land, preserving Ham Riverside Lands as a nature reserve. It has notably unusual vegetation due to the underlying alkaline rubble instead of the more acidic fluvial deposits. Engineering Towards the end of World War I, Lord Dysart sold some land south of Ham Common to the Ministry of Munitions for the construction of an aircraft factory on land adjoining what was then still called Upper Ham Road. National Aircraft Factory No. 2 was built in 26 weeks during the winter of 1917. The factory was