sentences:  Construction of the first transcontinental telegraph was the work of Western Union, which Hiram Sibley and Ezra Cornell had established in 1856 by merging companies operating east of the Mississippi River.A second significant step was the passing of the Telegraph Act by the Congress in 1860, which authorized the government to open bids for the construction of a telegraph line between Missouri and California and regulated the service to be provided.Eventually, the only bidder would be Sibley, because all competitors—Theodore Adams, Benjamin Ficklin and John Harmon—withdrew at the last minute.