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Reading 1
Reading 3



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Determining the Facts

Reading 2: Innovation on the Portage

The Allegheny Portage Railroad was a triumph of engineering. The levels and inclined planes of the railroad were an immediate improvement over the earlier wagon road through the mountains. Over the course of its short lifetime, improvements were continually made to the portage railroad. As one of the earliest railroads in the country, the Allegheny Portage was the scene of experimentation with railroad building and operational techniques.

Construction Techniques
The Allegheny Portage was the site of the first railroad tunnel built in America. Tunnels were still very new in the United States, existing on only a few canals. In fact, when first considering the idea of a "tunnel" to carry the canal through the Alleghenies in 1825, state engineers were obliged to define the term in their reports as "to be like a large well dug horizontally through a hill or mountain." The Staple Bend Tunnel constructed on the portage railroad cut through a ridge at the top of Inclined Plane No. 1. Its construction saved the railroad two-and-a-half miles of track that would have been needed if the railroad had followed the normal route of the valley in which it was being built. Today, of course, railroad and highway tunnels are common sights all over the country.

The portage railroad also experimented with track construction techniques. The rails on the level sections of the railroad were placed on stone blocks, called sleepers, spaced approximately every three feet along the road. Because these blocks shifted with weather and moisture variations, the rails often separated, making it impossible for trains to move safely along the tracks. Eventually wooden cross ties, as seen on railroads today, were placed along most of the railroad. The wooden cross ties, which bound the two rails together so they would not separate, were not as prone to movement and were much easier to prepare or replace.

Transportation Technology
The level sections of the portage railroad were a testing ground for early locomotives. The first locomotive to operate on commercial track in America had run in 1829 near Honesdale in northeastern Pennsylvania. When the portage railroad opened five years later, it did not have any locomotives. Horses pulled the cars, as was common on railways of the time. In 1835 the engine "Boston" became the first locomotive to run on the portage. It proved a huge success in reliability and power, doing the work of 18 horses. Over the next few years, the railroad acquired 16 other locomotives, and eventually phased out the use of horses. Proving their usefulness on early railroads like the Allegheny Portage helped locomotives become the dominant form of transportation by the end of the 19th century.

Railroad locomotives often had the unusual task of pulling boats along the railroad. As part of a canal system, the railroad’s job was to portage or carry canal traffic from one side of the Alleghenies to the other. At first this involved unloading all freight and passengers from the canal boats and loading them into rail cars for transport over the mountains. Eventually an ingenious system was devised to load specially built sectional canal boats directly onto railroad cars to be carried across the Alleghenies. They would then be reassembled on the other side and continue on their way. Today, when you see truck trailers on railroad cars, you are observing a modern version of this containerized shipment.

Inclined Plane Safety and Beyond
The inclined planes of the portage were a serious safety hazard during the early days of the railroad. The hemp ropes used to haul the cars up and lower them down the steep tracks often broke. Several fatalities resulted from cars crashing down the inclines. To prevent this occurrence, a brake was attached to the downhill side of the cars to prevent them from sliding down the incline tracks. This safety car or safety buck had sled-like runners which would drag on the track when the rope broke. The railroad car would then ride up onto the safety buck where the additional weight would activate a braking mechanism to slow the descent. This device prevented many accidents on the railroad.

In addition to their inherent safety problems, hemp ropes also were very expensive (costing about $3,000 per rope) and short-lived (lasting about 16 months). All of these problems were eventually solved with the installation of wire rope or cable on the inclines. This innovation had the most impact of any of the technological achievements of the railroad. It came about in 1841 when a man named John Roebling convinced the contractor who operated the boat slip at the Johnstown Canal basin to use a type of wire rope he had developed. This first experiment was a failure. Undaunted, Roebling developed a new rope and persuaded the railroad to try it on Inclined Plane No. 3. He obtained a position with the railroad and supervised repairs and adjustments to the machinery and this new rope. This time it was a success. Eventually all the inclines were fitted with Roebling’s wire rope. This rope or cable lasted years instead of months and did not break. His success on the portage railroad launched Roebling on a career that began the American wire rope industry. Roebling is best known for the suspension bridges he built all over the country, but his wire works provided cable for all manner of industrial development. His greatest project, the Brooklyn Bridge, was completed by his son. It stands today as the best heir to the technological legacy of the Allegheny Portage Railroad.

Questions for Reading 2

1. What was significant about the Staple Bend Tunnel? Why was it built?

2. Do you think the builders of the Allegheny Portage Railroad thought the railroad would last a long time? Why or why not?

3. What is a "sleeper"? What problems did it cause on the railroad? How were these solved?

4. What role did the Allegheny Portage Railroad play in the development of locomotives in this country?

5. How do you think the sectional canal boats were loaded onto railroad cars?

6. How did the railroad try to cut down on accidents before the hemp ropes were replaced with wire ropes or cables?

7. What were the advantages and disadvantages of hemp ropes and wire ropes used on the inclines?

Reading 2 was compiled from Anna Coxe Toogood, "Historic Resource Study for Allegheny Portage Railroad National Historic Site," National Park Service, 1973; William Bender, "The Evolution, Decadence and Abandonment of the Allegheny Portage Railroad" in The Pennsylvania Railroad Men’s News, September & October, 1897; and Donald Sayenga, "Roebling’s First Rope" and "Roebling’s Second Rope" in Wire Rope News, March & April, 1982.


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