114,397. Thuman, F., (Chrisman, C. S.). Nov. 7, 1917. Gases, washing.-The dip-pipe of a gas-washer is so constructed as to prevent undue vibration in the washer box and to reduce the back pressure by forming the pipe at its outlet end with a depending wall or walls, portions 8 of which form re-entrant spaces 9 so as to form an unusually large liquid-sealed rim, the pipe being so formed that its lower edge or edges are horizontal or at one level. As shown, the walls 8 are of quadrant form in section so that the spaces 9 are cruciform in cross-section, but the exact form of the spaces may be varied. The wash box may be supplied with water by a pipe 14 with a conical mouth, and with an outlet 15.