In addition to their operations against the Germans in France and Belgium, the Allies continued to carry the war into Germany. In a raid during the night of May 27 British long-distance bombing machines dropped between four and five tons of bombs on chemical works at Mannheim, the Landau railroad station, an electric power station at Kreuzwald, and on the Metz-Sablons railroad station. Very large explosions were caused and much damage done. The same night the important railway triangle at Liége in Belgium was bombarded. In spite of determined opposition by German airplanes, British aviators on May dropped bombs on factories and the railroad station at Saarbrücken in Rhenish Prussia. Cologne, the sixth largest city of Germany, was raided by British bombing planes on May 18. Bombs were dropped on railroad stations, factories, and barracks. Eighty-eight of the persons who were killed were buried in the same grave. The people of the city became panic-stricken. Aix-la-Chapelle was also attacked and factories set on fire. TONS OF BRITISH BOMBS British air squadrons carried out successful raids in Germany on May 31. Long-distance bombing machines crossed the Rhine and, in spite of strong opposition from enemy aircraft, dropped over a ton of bombs on the station and workshops at Karlsruhe. Another group of British airplanes dropped a ton of bombs on the railway triangle of Metz-Sablons with good effect and without losses. During the course of the day thirty-one tons of bombs were dropped on different targets behind the enemy lines. Twenty German machines were destroyed in air fighting, and six were driven out of control. During the night sixteen tons of bombs were dropped on targets in enemy territory. Six tons were dropped on the Bruges docks and on the Zeebrugge-Bruges Canal. In addition, four tons were dropped on railway junctions and the stations at Metz-Sablons, Karthaus, and Thionville.