Last of the Wooden Walls: An Illustrated History of the Ton Class Minesweepers and Minehunters (Hardback)

At the end of the Second World War it was generally accepted that the emphasis on mining had shifted from deeply laid moored mines to ground mines laid in the shallow approaches to ports and harbours. A design team was formed in Bath in 1947 and by 1949 had produced two designs of an advanced concept for inshore and coastal work. The onset of the Korean War and discovery of new, highly sensitive, Russian magnetic mines accelerated production of the non-magnetic Coastal Minesweeper. The result was a very sturdy and flexible craft, with a double mahogany hull over an aluminium frame, with nonmagnetic fittings, capable of undertaking ocean passages, and able to sweep both moored and ground mines. Upperworks and many of the fittings were constructed from light aluminium alloy and other materials with the lowest possible magnetic field, to achieve optimum safety when sweeping for magnetic mines. The ships were protected from pressure mines by their low displacement and the threat from moored mines was greatly reduced by their shallow draught. The ships were originally to have been named after insects, perhaps recalling the gunboats on the China Station in the 1920s, but in 1952 this proposal was dropped and the TONs were named after villages ending in