Report - - Royal Gunpowder Mills (Herts) March 2013 | Military Sites | 28DaysLater.co.uk

Report - Royal Gunpowder Mills (Herts) March 2013


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Intro report hope you enjoy


This very secret location has been involved in the production and development of explosives and rocket propellants for over 300 years.

The site is set in 170 acres of woodland and this part of the site was referred to as the island due to the network of canals. Much of the water network is man-made, feeding off the River. Water was crucial both to the manufacturing process and the transport of explosives.

The production of explosives on the banks of the River began during the 17th century. In the parish records of the period 1660-1670 there are burials listing accidents at the site as the cause of death. In the early days the production of gunpowder was a commercial venture using water as a source of powder, but in 1787 the government purchased the site to ensure a high quality supply. Nowadays only a few remains of the original buildings are visible as you cross the water soon after entering the site. The oldest surviving building is W***** House, a two-storey building constructed just after the acquisition by the government and now used by the current administration.

The production proved inadequate during the Crimean War (1854-1856), so afterwards it was decided to increase productivity by installing mills powered by steam. On the east side of the large rectangular grassy area can be seen a line of buildings begun in 1861. In the centre of each building, where there is the high window, there was a large steam engine. Two shafts under the floor transmitted the power to six incorporating mills (three each side), where the wet ingredients of gunpowder were mixed and ground. These buildings were converted into laboratories after the Second World War, but the most southerly one has been partly restored. There you can see the remains of the machinery made in the Victorian era.

It was necessary to bring in the saltpetre and the sulphur, but the site could produce its own charcoal. There are still many alder trees, which produced wood ideal for making charcoal. The alders can be recognised by their almost circular deciduous leaved and their seed containers, which resemble miniature fir cones.

Gunpowder was mostly used as a propellant, but it produces a lot of smoke and so reveals the location of the gun. The discovery of smokeless propellants towards the end of the nineteenth century ensured the decline of Gunpowder production. Cordite, which contains nitrocellulose and nitro-glycerine, became the preferred propellant of the twentieth century. There were also new high explosives to be produces. Additional areas both to the north and to the south were acquired for the new processes. Today there is little to be seen of such developments to the south, where modern residential and commercial buildings are to be found. The most northerly area has become a nature reserve, noted for its deer and herons.

Some eight kilometres of canal were constructed for transporting materials within the site. The system has two levels, connected by a lock, and aqueducts. Today the upper canals are dry, but the lower ones still contain water. A barge for transporting explosives is on display, and also footbridges designed to be compatible with the shape of the barges. The canals could not cope with the increased production from six thousand munitions workers during the First World War, so the narrow gauge (18 inch or 450 mm) railway system was developed, remains of which can be seen in some places.

The expansion in output for the Second World War was not so great because enemy bombers could reach the site too easily. The government preferred to set up new installations in Scotland and Wales. Large-scale production had ceased by the end of the war afterwards the site became ERDE, the Explosives Research and Development Establishment of the Ministry of Defence. Later rationalisation of research on explosives and armaments led to the departure of all the scientific staff by 1991.........Anyway on with the pics
















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