A historical novel about one man's experience of the evacuation of Dunkirk: "A lively tale around one of the turning points of World War II" (The New York Times).   Sergeant Edward Williams of the Second Battalion was among the first British troops to land in France, just across the English Channel from his family in Dover, after the declaration of war in September of 1939. Battles have been few and far between since then, in what the Germans have been calling der Sitzkrieg--the sitting war.    In May 1940, under the leadership of their new prime minister, Winston Churchill, the British are hoping to stem the tide of Nazi invasion along their southern border. But now, flanked to the east and west by German troops and cut off from the Allies further south, Sergeant Williams and his battalion must retreat to Dunkerque in the north, and escape by sea is their only hope.