Docklands History Group Meeting October 2002 the Defences of the Thames by Victor Smith

Docklands History Group meeting October 2002 The Defences of the Thames By Victor Smith Victor started by explaining the need for fortifications to defend the river and in particular the docks. By Henry VIH’s reign eighty per cent of England’s exports used the Thames. It was the hub of the Empire with dockyards and shipping, the arsenal at Woolwich, gunpowder magazines at Purfleet and the starting point for mercantile and naval expeditions. Guns were set up to fire from the shore but it had to be born in mind that defences were not just fortifications on land. The first line of defence downstream was the Navy. On shore it was the army. Up to the sixteenth century fighting was ship to ship or hand to hand when an enemy landed. After this time there was effective gunpowder and artillery grew in importance. Some defences were local, such as Cooling Castle. At Gravesend the Thames narrowed and guns could be sited to attack enemy warships. However, picket ships, block ships, boom ships and chains were still needed. After the 1530 continental invasion the first national scheme for artillery fortifications was drawn up. Block houses were built, including one at Gravesend and one at Tilbury. They had twenty to twenty-five guns each with a range of 1,000 metres. At Gravesend cross fire was used to cover the whole of the river, but ricochets could be a problem. At the time of the Spanish Armada there was a boom defence and a camp at West Tilbury. In the Civil War Parliament used the Gravesend and Tilbury blockhouses as check points. After the Dutch raid of 1667 new temporary Trinity forts were built. These were linked to Trinity House, but it is not known where they were located. There was a naval battle off East Tilbury. The authorities were criticised because the block ships they had sunk were said to be too good. Tilbury Fort has arrowhead bastions. The barracks were built to house the national standing army. In 1690 the Fort was criticised because it only provided protection for the fort itself, and none for the river. The gun line was added later outside. In 1799 forts were built at East Tilbury, Shornemead and Hope Point. A new pattern traversing gun platform was introduced. The platform moved in an arc on metal rails and the gun ran on an inclined frame. During the Napoleonic wars, ships were moored across the mouth of the Thames. In the 1840s Shornemead fort was replaced with a polygonal fortification. Martello towers were built. Steam ships emerged which were resistant to round shot. By the 1860s there were wrought iron shields and concrete to protect the guns. Optics and electric searchlights, telephones and telegraphs and armoured steamers made the old defences redundant. Weapons were now placed at low level to blend into the landscape and were able to traverse. In the 1890s came the Brennan torpedo. Cliffe fort was a launching bay.In the world wars came air defence gun zones, balloons, pill boxes, and trench systems in Kent and Essex. Warden Point had a concrete acoustic mirror to catch aircraft noise. Radar towers and towers to detect mine laying aircraft and off shore forts in the Estuary were built. There were mine watch posts to look for parachute mines landing in the river and a boom from Canvey Island to the Kent shore. There were also electronically operated minefields, and anti-tank and other beach defences. Victor ended by explaining that the jet engine made fixed defences vulnerable. In 1956 the gun defences had been abandoned. With the advent of NATO, the Thames had ceased to be “strategic” and so it no longer required defences. There were strategic warden posts, and nuclear bunkers in the vicinity, but these were not created as part of the Thames defences..

Load more