The Battle of 3rd Ypres (Passchendaele) (The edited text of a paper given in France in November 1993. The original paper was illustrated by contemporary slide photographs and maps; this text is best read in conjunction with a map of the area.) In 1915, at the second Battle of Ypres, the Germans used chlorine gas for the first time in warfare and succeeded in driving the British back to the town of Ypres. Here a bulge, or salient, was formed in their front line which left the town exposed on three sides to shellfire. The town was gradually destroyed, although of course it continued to be used as an important military centre