Railroads in the 1850s was a further transpiration of the 1840s and led to an even greater explosion of new railroads and construction. Aside from the tripling of new mileage from 1840, and another tripling by 1860, the decade saw further technological improvements, so much so that train speeds had increased to the point that one could reach Chicago from New York in just two days or so. The decade witnessed railroads break across the Mississippi River into Texas and plans made for the push across the continent to California and the west coast (as gold was discovered there during this time). It would not be long until the idea of a transcontinental railroad was proposed, an act that became reality in the early 1860s thanks to President Lincoln.
While the country's rail network continued to rapidly grow after the 1840s much of it continued to be concentrated in the Northeast and Midwest, which would help to play a vital role in the Civil War a decade later. Looking a map of the rail network from the decade it's amazing at just how much trackage was built during the decade. By the end of the decade a sparsely built Midwest became a plethora of rail lines radiating in every direction, particularly in the states of Ohio, Indiana and Illinois. While the south also saw a substantial increase of its rail network it wasn't quite as explosive as what transpired in the north. The decade began with with only 9,021 miles and finished with nearly 30,000!
Railroads of the era also saw the creation of the New York Central in 1853 through the merger of the Mohawk & Hudson and several smaller systems and the railroad would go on to be one of the largest in the east. The other two major eastern trunk lines, the Baltimore & Ohio and Pennsylvania Railroads continued their push westward past the Ohio River and reaching Chicago and/or St. Louis. Chicago was fast becoming the "central hub" of the industry as it was already served by eleven railroads during the decade. Around the Mississippi River the Illinois Central was opened in 1856 stretching over 700 miles, the first railroad ever of such length. Also, in 1859 a passenger car built by George Pullman took to the rails for the first time and the company he started would go on to be the largest and most profitable builder of passenger equipment in the country by the early 20th century.
New developments took place during this era. First, the federal government began granting railroads large tracts of western lands to build and develop new areas west of the Mississippi (in this instance the granger and plains regions). Second, the telegraph made its first test in railroad applications during 1851, although it had been conceived in the 1830s. This new system allowed railroads near instant communication, in coded dots and dashes, and spurred the building of lineside poles along most rail lines that became a common part of the railroad landscape. Railroads in the 1850s also saw a major shift in traffic flow. Before trains became a reliable means of transportation the fastest way to move people and goods was by rivers and waterways.
For this traffic to move from the east coast to Midwest meant using the Ohio and Mississippi Rivers which flowed in a predominantly southern direction, eventually reaching New Orleans and the Gulf of Mexico. With railroads building directly westward into Ohio, Indiana and Illinois traffic could flow directly east-west with Chicago fast become the terminating western hub because of its location along Lake Michigan. The city also was the ideal northern terminating point for railroads built north-south such as the Illinois Central and after the western railroads opened they chose Chicago as their eastern terminating hub since so many railroads already served the city and interchanged people and goods there.
Railroads in the 1850s and the expansion that took place during the decade set the stage for what would transpire during the Civil War and how the campaign transpired. The North would hold a commanding advantage in the war not only because most of the country's industrial base was centered in the Northeast but also because most of the railroads with most of the trackage centered in the Northeast and Midwest (it also didn't help that since much of the war was fought in the South significant infrastructure was damaged or destroyed). Aside from the war other factors that were becoming issues in the 1860s included many different track gauges which were affecting traffic interchange and the number of bridges crossing major waterways.