What railroad for which Oakes Ames is credit as being the single most important influence in building was caught up in the  Crédit Mobilier scandal?
Crédit Mobilier of America scandal The Crédit Mobilier scandal of 1867, which came to public attention in 1872, involved the Union Pacific Rail Road and the Crédit Mobilier of America construction company in the building of the eastern portion of the First Transcontinental Railroad. The scandal was in two parts. The construction company charged the railroad far higher rates than usual, and cash and $9 million in discounted stock were given as bribes to 15 powerful Washington politicians, including the Vice-President, the Secretary of the Treasury, four senators, and the Speaker and other members of the House.
Railway Express Agency The Railway Express Agency ("REA") was a national monopoly set up by the United States federal government in 1917. Rail express services provided small package and parcel transportation using the extant railroad infrastructure much as UPS functions today using the road system. The United States government was concerned about the rapid, safe movement of parcels, money, and goods during World War I and REA was its solution to this problem. REA ceased operations in 1975, when its business model ceased to be viable.