Standardization of Screw Threads Commission. Extending life of Screw-Thread Commission, and Authorizing coinage of memorial 50-cent piece for State of Maine, hearings on H. J. Res. 299, extending life of National Screw-Thread Commission for period of 2 years from Mar. 21, 1920, and H. R. 12460, to authorize coinage of 50-cent pieces in commemoration of 100th anniversary of admission of Maine into the Union; Feb. 23, 1920.