LETTERS written by a seaman who survived the sinking of the Titanic and its sister ship the Britannic four years later only to die in a German torpedo attack are expected to raise up to 20000 at auctionArchie Jewell was on board the Titanic on the night of 14 April 1912 and his writings describe the horror of watching the great ship sink and hearing the cries of passengers drowning in the icy seas