The Experimental hypervelocity gun located near St. Margaret's Bay near Dover. This gun was named Bruce, heres some links to more detailed information:
kenthistoryforum:
http://www.kenthistoryforum.co.uk/index.php?topic=5903.0
sussexhistoryforum:
http://sussexhistoryforum.co.uk/index.php?PHPSESSID=qd304hlnp3rf8ijmm028k7mlf6&topic=453.0
du.kent-history:
http://www.du.kent-history.co.uk/1/bruce/bruce.htm