jul 1, 1862 - The Pacific railway act was signed.
Description:
The Pacific railway act was signed on July 1 1862. It admitted the Union Pacific and the Central Pacific to continue building eastward and westward. The government advertised giving 6,400 acres of land to build the railroad on and 48,000 to spend on each mile built.
https://www.shmoop.com/transcontinental-railroad/timeline.html
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