113,505. Simpson, W. S. March 5, 1917. Tungsten oxides.-Distilled water, or other liquid, is exposed while moving as a stream, film, or spray to particles of tungsten trioxide projected from an electric arc between tungsten electrodes. The oxide is stated to become permanently suspended in the liquid, which may be employed for curative purposes. In the apparatus shown, the electrodes 4, adjusted by hand or automatic gear 3, enter a cylinder 2a passing through the bottom of a casing 1. Above the arc is a perforated distributor 6 on a rotating hollow shaft 5 communicating with a reservoir 7. The centrifugally - projected liquid is received in the annular space 11 around the cylinder 2<a>, and is drawn off for use by a tap 14 or returned to the reservoir 7 by means of pipes 12, 13 and a pump 15 driven by the same motor as the rotary shaft. A single treatment with a 100-ampere arc is sufficient, the output being 60 gallons per hour, but it is preferred to employ a smaller current, say 15 amperes, and longer exposure, so as to produce 10 gallons per hour.