How did the advance of technology in the nineteenth century allow the dream of a transcontinental America become a reality?

Railroads

Explanation:

There was a time when moving West took a lot of courage. traveling from the East coast to the West coast meant riding for months in a horse drawn wagon, but all that changed when the America's first steam locomotive made its debut in 1830 and over the next two decades, railroads tracks linked many cities on the East coast.

The railroad construction had a profound effect on the country likewise the many other transcontinental lines that followed it. The railroads spawned the first massive corporations, linked many towns and cities and unleashed labor demans.

Industrialization remade much of American life because technological innovation accompanied economic development.