Railroad safety--Supplemental hearings. Hearings before a subcommittee on the Committee on Interstate and Foreign Commerce, House of Representatives, 81st Conbgress, 1st session on H.R. 378, a bill to amend section 25 of the interstate commerce act to require certain common carriers by railroad to install and maintain communication systems and to establish and observe operation rules, regulations, and practices to promote safety of employees and travelers on railroads, and for other purposes; H.R 530, a bill to promote the safety of employees and travelers upon railroads, and to protect the public by requiring certain common carriers by railroad to install and maintain communication systems, and for other purposes. August 4-9, 1949.