Site Records

Site Name: Hoo Fort

Medway Estuary
North of Gillingham
OS Grid Ref: TQ797703

Sub Brit site visit 9th September 2007

[Source: Ron Crowdy (historical text) & Nick Catford]

The forts on Hoo & Darnet Islands in the Medway estuary were built on the recommendations of a Royal Commission in 1859. The Commission was appointed because of the political situation in Europe in the late 1850s. The countries of Europe were engaged in a feverish bout of pact signing, with each country anxious to secure as many allies as possible.

France had been using the latest designs in powerful new rifle-barrelled artillery (RML's) and had equipped her navy with modern 'iron-clad' warships. At this time France was the only country other than Britain, engaged in expanding her territories. The recently opened Suez Canal opened up the possibilities of France expanding her colonies much more easily in the 'Far East'. Fears were voiced over France's expected ability to blockade the Mediterranean whereby any Franco-British conflict in the east, particularly India, would leave Britain having to supply her garrisons via the Cape Route, thus seriously affecting the possible outcome.

Photo:Hoo Fort from the air in April 2007
Photo by Freddie Smith Aeropix

Napoleon III

Tension was heightened when, in January 1858, Napoleon III survived an attempt on his life by an Italian named Orsini, who was angry at the apparent failure of Napoleon III to press for the reunification of Italy at a conference in Paris, where the support of France would have helped his cause. Britain was known to be sympathetic to his cause.

The situation became tenser when Austrian forces, inexplicably attacked French forces supporting the Piedmontese in Italy. Rumours in Britain at this time spoke of the whole of Europe at war and an invasion of Britain imminent, with a force being assembled in France

The British government decided to act and set up a Royal Commission to "consider the defences of the United Kingdom”. The Commission acted quickly and reported back the following year, 1860, with comprehensive suggestions for the improvement of the country's defences. Among these suggestions were plans to improve the defences of the Medway area. An extract from the commissioners' Report of 1860 reads (after describing the geographical importance of the area) "These circumstances combined with the growing importance of Chatham and the fact that it is our great Naval Establishment in the Eastern part of England have led us to the conclusion that there are abundant reasons for adding very considerably to the existing fortifications".

The commission covered all aspects of defence for the area and among their proposals was a suggestion for the placing of two identical forts on the Medway Islands of Burntwick and Oakham Ness. The forts were to be placed on either side of the main Medway channel, the idea being to control the channel with a boom between the two islands, whilst defending the approaches by means of two powerful batteries of guns. The forts were to be circular in design with two tiers of guns with a third, lower tier for the magazines.

Photo by Bob Le Roi from his web site

The total cost of the Royal Commission's proposals for the Chatham area were estimated at £11,000,000, but after economies and cuts to the programme, the eventual cost was c £7,500,000.

This is on the authority of General Linthorne Simmonds in a letter to 'The Times' in January 1884. Once voted, the money’ was put at the disposal of The Inspectorate of Fortifications to carry out the proposals. The Inspector General at that time, was Sir John Burgoyne, but the credit must go to Major William Jervois (later Sir W. F. Drummond Jervois) of the Royal Engineers for persuading the Commission to spend the major proportion of funds available on permanent fortifications, rather than on increasing the power of the Navy and the building of temporary earthen batteries. Major Jervois R.E. was a brilliant planner and gave the task of designing the forts in the Medway area to one of his talented deputies, Captain Siborne R.E.

Major Jervois R.E.

There seemed to be no problems with the chosen sites, especially as there was an 18th century battery at Oakham Ness, but surveyors were to find both sites unsuitable for such heavy structures - the ground being too soft to bear the enormous weights of the forts and their guns (a seven-inch gun weighed nearly nine tons); alternative sites had to be found. A new survey was commissioned to assess the only other comparable sites, the islands of Hoo and Darnet where the earlier batteries of Hoo Ness and Pinnams were located. The survey was carried out and borings were taken to a depth of 18 feet at Hoo and 28 feet at Darnet. Hoo was shown to have a subsoil of sand and clay, but the boring at Darnet showed a composition of different layers of soil, sand and thin layers of peat.

Photo:The entrance to Hoo Fort
Photo by Nick Catford

In October 1861 an experimental pile was driven at Darnet to a depth of 50 feet. It was noted that little resistance was met by the pile whilst at Hoo several blows were sometimes needed to drive the pile only a single inch. However it was decided that if the depth of foundations at Hoo were altered from eight to ten feet and at Darnet from eight to fifteen feet, the sites would be able to bear the weight of the new forts

Click here to continue the history of Hoo Fort

[Source: Ron Crowdy (historical text) & Nick Catford]

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