Tracks Through Time

Tracks Through Time. . The first permanent railroad track in the United States was laid around 1810 near Philadelphia. Experimental railways began developing throughout the eastern states and by 1850 over 9,000 miles of track had been laid. Track construction followed the country's westward expansion and by the time of the Civil War nearly all the important cities of the east, midwest and south were linked by rail. On May 10, 1869 the last spike was driven on America's First Transcontinental Railroad - connecting the Atlantic and Pacific Oceans by rail. , The background photo, taken in October 1866, depicts a Union Pacific Railroad construction engineer looking out over the transcontinental right-of-way; rough-hewn wood ties are all in place on the freshly-graded roadbed, awaiting the rail-laying crews. America's railroad track miles continued to grow to a peak of over 252,000 miles in 1920. About 140,000 miles of track were in operation in 2011. , Over the last 200 years, track engineering and construction technology has continuously improved, allowing trains to be heavier and faster. Displayed on the ground before you are three examples illustrating some aspects of this technological development. , Photo captions and display panels: , Display Panel “A” shows track typical of the 1860s, with 56-pound rail on rough-hewn ties. , Early track construction required many workers - with all the grading work and track-laying done with simple hand tools. The workers pictured here were mostly Chinese immigrants, building eastward in the Nevada desert on the Central Pacific portion of the First Transcontenential Railroad, circa 1868. "End of Track on the Humboldt Plain." Photo by Alfred A. Hart. Library of Congress collection. , Display Panel “B” shows track typical of the 1940s, laid with 90-pound rail on milled and treated wood ties. , Railroad tracks require constant maintenance to keep them straight, level and safe for passing trains. Track maintenance continued to be a labor-intensive operation throughout the 20th Century. Pictured here is a gang of Santa Fe Railway "Gandy Dancers," a nickname derived from the "dancing" motion of the track workers as they moved their tools in unison to nudge the rails, often rhythmically timed by singing a musical chant. Santa Fe Railway photograph, courtesy Kansas State Historical Society. , Display Panel “C” shows a section typical of machine-laid track, with concrete ties. , Today, most mainline track construction and maintenance is done by a series of machines. This view of a mechanized system using concrete ties and continuously-welded rail is on the Adelaide-Darwin Railway in Australia. Photo by Ken Hodge, Creative Commons Attribution. , Railroad Track Terminology: , The distance between the inside edges of the rails is called the Gauge. , Crossties hold the rails apart at the proper gauge. , , Ballast helps drain away water and keeps the ties in place on the roadbed. , Rail size (weight) is given in number of pounds per 3-foot piece of rail. , Tie Plates and Spikes hold the rails onto the ties. , Flange keeps the wheels on the rails.