Photographs & History

Photographs and History

Managing the Line: Communications on the A&S

This 1906 view shows the wood frame tower at Quarryville (Milepost 10.8), the first interlocking tower west of Parkesburg. "Q" had control over the two main tracks and four additional sidings to manage helper movements assisting trains to Mars Hill Summit. Additionally four water columns were available to top off steam locomotive tenders on their journey east or west. Image collection of William L. Seigford

This 1906 view shows the wood frame tower at Quarryville (Milepost 10.8), the first interlocking tower west of Parkesburg. "Q" had control over the two main tracks and four additional sidings to manage helper movements assisting trains to Mars Hill Summit. Additionally four water columns were available to top off steam locomotive tenders on their journey east or west. Image collection of William L. Seigford

Running over 53 miles in length the PRR's Atglen & Susquehanna Branch was a shining example of modern railway construction, running across rolling countryside and up the Susquehanna River on a gentle gradient. Fittingly for such a contemporary piece of railroad engineering, another advancement of modern times accompanied the line; the telephone. By the time the A&S opened for business in 1906, the PRR was rapidly working towards constructing one of the world's largest private telephone networks, laying cable along its system for critical functions like dispatching trains in addition to providing an extensive "in-house" communication network. The PRR's interest in telephone technology dates back to 1877 when officials invited Thomas A. Watson, assistant to Alexander Graham Bell for a demonstration in Altoona. While the railroad made a modest investment for non-critical communication following this meeting, it wouldn't be until 1897 when the technology was employed to dispatch trains entirely by phone on the South Fork Branch of the Pittsburgh Division.

The Pennsylvania Railroad maintained standard plans for watch boxes and telephone shelters among countless other items on the property. These structures were common along the Atglen & Susquehanna Branch; At one point there were 11 watch box locations in addition to line side telephones were spaced approximately 1.25 miles to provide direct contact with block operators and dispatchers in the event that a track inspector needed to report a problem with the line. Collection of Pat McKinney, courtesy of  Rob Schoenberg's PRR page

The Pennsylvania Railroad maintained standard plans for watch boxes and telephone shelters among countless other items on the property. These structures were common along the Atglen & Susquehanna Branch; At one point there were 11 watch box locations in addition to line side telephones were spaced approximately 1.25 miles to provide direct contact with block operators and dispatchers in the event that a track inspector needed to report a problem with the line. Collection of Pat McKinney, courtesy of Rob Schoenberg's PRR page

As technology was improved, the PRR began investing heavily in building a communication network, and by 1920 almost the entire system was dispatched by telephone. East of Paoli in the electrified territory, cable was laid in an underground duct system, west of Paoli the cable lines were often above ground on lineside poles and west of Harrisburg an extensive line side open wire system was employed. By 1955 the PRR boasted some impressive statistics in their company magazine, The Pennsy stating, "Today the PRR's network is generally accepted to be the largest private telephone system in the world. Its transmission lines stretch 41,000 miles. It's cost, together with that of the associated Teletype network, totals $35 million. On any typical day, PRR lines carry an estimated half-million calls." 

With the start of operations, the A&S was dispatched by phone from Harrisburg, out on the line local control via eight block stations provided the means for changing tracks and relay orders to passing trains. These included Parkesburg (PG), Atglen (NI), Quarryville (Q), Shenks Ferry - (SF - later Smith), Cresswell (CO), Columbia (LG-42), Marietta (RQ) and Wago Junction (WJ). Additionally, the PRR constructed 11 watch boxes along the A&S that were staffed 24/7 due to the continuous risk of washouts and cave-ins with the numerous cuts, fills, culverts and bridges along the line. Track inspectors could reach dispatchers via the watch boxes or line side phone boxes spaced roughly every 1.25 miles for field access in the event a situation should arise.

L.  Shenks Ferry (Smith) interlocking tower circa 1967. This tower survived the electrification and addition of automatic block signals in 1938 and was employed as needed in the event of a wreck or track work in the area. Photo by William R. Fry, Jr.  R.  LG27, one of 11 watch boxes on the A&S Branch, located just west of the Safe Harbor Viaduct where sharp cliffs and rock cuts posed concerns. These were staffed 24/7 and equipped with the necessary tools, a stove and telephone box for inspectors to conduct their work while staying in constant contact with block operators and dispatchers. Collection of the Southern Lancaster County Historical Society

L. Shenks Ferry (Smith) interlocking tower circa 1967. This tower survived the electrification and addition of automatic block signals in 1938 and was employed as needed in the event of a wreck or track work in the area. Photo by William R. Fry, Jr. R. LG27, one of 11 watch boxes on the A&S Branch, located just west of the Safe Harbor Viaduct where sharp cliffs and rock cuts posed concerns. These were staffed 24/7 and equipped with the necessary tools, a stove and telephone box for inspectors to conduct their work while staying in constant contact with block operators and dispatchers. Collection of the Southern Lancaster County Historical Society

Consolidation of block station and train order offices began during the Depression, with Quarryville placed out of service on August 11th, 1928. More change in operations came with the final phase of electrification completed in 1938. The project, which included the installation of automatic block signals and the implementation of established Current of Traffic Rule 251 eliminating the need for intermediate manned block stations. An additional benefit of the signal system was the integration of slide detector fences in areas prone to rockslides, eliminating the need for staffed watch boxes. Cola tower opened in Columbia sporting a 120 lever centralized traffic control machine, dispatching over 175 miles of freight only territory.  Under its jurisdiction on the A&S were Cresswell, LG-42 and Marietta (Shocks) as well as trackage down the Port Road south to Holtwood. Parkesburg was also rebuilt, relocated to a one of a kind brick single story building, containing a 39-lever Union Switch & Signal Model P interlocking machine. The last block station of note proved to be a bit of mystery, NI at Atglen just a few miles west of Parkesburg closed sometime between 1928 and 1945 based on various employee resources, but at this time I have found little else to narrow the dates of its demise. By the time electrification was complete all but one remaining manned block station survived on the A&S between Parkesburg and Cola; Shenks Ferry (SF), later renamed Smith, was retained as a part-time facility due to its location approximately midway between Cress and Parkesburg. While Smith ultimately met its demise, Cola survived into the Conrail era, closing in March of 1987, followed by the A&S in 1988. On the opposite end of the line, Parkesburg survived well into the 21st Century under Amtrak. The closing of Parkesburg during the Keystone Corridor improvements was the first in a string of tower closures that mark the end of an era in technology and dispatching that lasted longer than the company that helped pioneer the technology.

 

The Paoli Local: 100 Years of Electrification on the Pennsylvania Railroad

At 5:55 AM, Saturday, September 11th 1915 the first scheduled electric powered train departed Paoli for Philadelphia marking the beginning of one of the most famous railroad electrification projects in the United States. 

Overbrook Station marks the location where the Pennsylvania Railroad crosses from the Philadelphia city line into the suburban district knows locally as the Main Line. This location is full of PRR character including the station built in 1860, a PRR standard design interlocking tower and the original details from the first phase of the PRR's great electrification project. 

Overbrook Station marks the location where the Pennsylvania Railroad crosses from the Philadelphia city line into the suburban district knows locally as the Main Line. This location is full of PRR character including the station built in 1860, a PRR standard design interlocking tower and the original details from the first phase of the PRR's great electrification project. 

At the close of 1910 the Pennsylvania Railroad had certainly accomplished some remarkable projects. The building of Penn Station and the Hudson and East River Tunnels was an engineering feat that put the railroad at a major advantage over many others, giving them direct access to New York City while establishing a through connection to New England markets.  Out of necessity the new terminal utilized trains running on a proven direct current third rail system, as steam engines would literally suffocate passengers in the lengthy tunnels. The PRR had already begun utilizing DC propulsion on routes previous to the terminal as a way to economize operations and included subsidiaries Long Island Railroad and part of the West Jersey & Seashore. To the north the New Haven had just inaugurated heavy electrified main line service utilizing a new alternating current installation in 1907, but with little time to observe the New Haven’s technology the PRR’s conservative management instead chose the proven DC system.

Soon after the New York terminal project was completed, engineering forces turned their attention to a major traffic bottleneck in the PRR’s corporate home of Philadelphia. Broad Street Station, built by the Wilson Brothers in 1881 and expanded by Frank Furness in 1892-93 was a 16-track stub ended terminal that was situated in the city center directly across from city hall. Broad Street saw a host of trains including commuter and long distance trains that stopped, terminated or originated here; because of the nature of a stub end terminal and a lengthily and congested reverse move to the engine facilities west of the Schuylkill River, trains faced a host of delays limiting Broad Street’s capacity and efficiency. In order to ease congestion the PRR turned to engineering consultant Gibbs & Hill to develop a solution utilizing electric traction, but this time with AC propulsion. Now several years into the New Haven’s electrification the PRR could capitalize on their triumphs while incorporating technological advances to perfect the new installation. A simplified infrastructure and commercial power purchased from Philadelphia Electric made AC propulsion very economical over DC which required the railroad to construction dedicated power plants. With a supply agreement in place the PRR and Philadelphia Electric could easily expand the network over the next several years, sharing the power generation expansion cost with other commercial and industrial customers.

The western terminus of the 1915 electrification was Paoli, Pennsylvania just 20 miles west of Broad Street Station. Here in a modern view we look west toward the interlocking tower and former shop facility used to service the MP54 MU cars. Telltale details of the 1915 electrification include both the lattice style and tubular trolley poles that support the catenary system. Note: This photograph was taken with Amtrak permission under watchman protection, the author does not condone any type of trespassing on railroad or private property. 

The western terminus of the 1915 electrification was Paoli, Pennsylvania just 20 miles west of Broad Street Station. Here in a modern view we look west toward the interlocking tower and former shop facility used to service the MP54 MU cars. Telltale details of the 1915 electrification include both the lattice style and tubular trolley poles that support the catenary system. Note: This photograph was taken with Amtrak permission under watchman protection, the author does not condone any type of trespassing on railroad or private property. 

The initial phase of electrification would be a costly investment due to the complexities of the Philadelphia Terminal’s trackage.  Once completed however, it could not only support electrified Paoli service but also main line service to Wilmington, Trenton, the West Chester Branch and Chestnut Hill branch freeing up valuable terminal space while maximizing the benefit of the initial cost. Power would be supplied by the Schuylkill River generating station and transmitted across the river to the Arsenal Bridge sub-station then on to the West Philly, Bryn Mawr and Paoli sub-stations. Here the 25 cycle 44,000 volt single phase power would be stepped down to 11,000 volts and fed to trains via overhead trolley lines supported by cable suspension supports strung between tubular steel trolley poles. The route to Paoli was 20 miles in length and electrification included wiring a coach yard and service facility in the West Philadelphia shops as well as a new facility in Paoli, a total of roughly 93 miles of track. Initially limited to just the Paoli commuter runs the electrification would power some 80 plus trains a day while affording an 8% overall increase in capacity at Broad Street. Though this seems like a small advantage for such a significant investment, the PRR looked to the future making this the first of several steps to dramatically increase capacity by expanding electric operations off the initial hub.

Two of the original sub-station buildings still survive along the main line at Bryn Mawr (L) and Paoli (R). Note to the right of the Paoli sub-station the vacant land which was the location of the Paoli shops.

Two of the original sub-station buildings still survive along the main line at Bryn Mawr (L) and Paoli (R). Note to the right of the Paoli sub-station the vacant land which was the location of the Paoli shops.

While planning, design and construction of the Paoli electrification was taking place, the PRR turned to the proven class P54 steel coach that was already in production. Though only a basic coach design the PRR had incorporated provisions in the plans to accommodate electrification and operating components when it was time to develop a fleet of self-propelled multiple unit (MU) cars. These motorcars would largely makeup the initial fleet of the PRR’s electric operations until suitable locomotives were developed to haul long distance trains. Classified as MP54's many were already in electrified service on the Long Island and WJ&S utilizing DC propulsion. The MP54 fleet eventually comprised of over 1400 cars; 480 ran on the PRR proper, 923 on the Long Island Railroad and 18 on the WJ&S /PRSL, some of which outlasted the PRR itself, remaining in operation through 1981.

Detail of the Union Switch & Signal interlocking machine at Paoli tower. Though still in service the interlocking plant here and the facility's importance has been greatly reduced with the elimination of the shops. The model board reflects the abandoned #2 and #3 main tracks west of the interlocking. 

Detail of the Union Switch & Signal interlocking machine at Paoli tower. Though still in service the interlocking plant here and the facility's importance has been greatly reduced with the elimination of the shops. The model board reflects the abandoned #2 and #3 main tracks west of the interlocking. 

With the first phase of electrification a success the railroad continued expansion from the Broad Street terminal, next on the Chestnut Hill branch in 1918 and the White Marsh branch in 1924. Concurrent to the expansion of the PRR’s electrified network other notable projects commenced, one of great importance was the Philadelphia Improvements. With heavy construction beginning in 1927 the PRR sought to replace Broad Street Station with a new subterranean station and office tower called Suburban Station and Penn center respectively. All north-south oriented main line trains would utilize a new through station on the west bank of the Schuylkill River called 30th Street Station. East-west trains utilized an upgraded facility out on the main line in North Philadelphia to eliminate the need to reverse out of the terminal to continue after stopping since 30th was actually off the New York-Pittsburgh Main Line. Commuter trains in and out of Suburban would also service 30th Street from a separate upper level reducing the concentration of travelers separating commuter operations from the long distance and regional trains. 

Though the massive Philadelphia Improvements took years to complete electrification continued at a rapid rate extending south to Wilmington on the main line including the branch to West Chester in 1928 and north on the main line to Trenton and the Schuylkill Valley Branch to Norristown in 1930 completing the electrification of all Philadelphia region suburban lines. Further studies reiterated the economical advantage of electrification outside the commuter zones for regional and long distance trains between New York, Philadelphia, Washington DC and Harrisburg, prompting PRR president William Wallace Atterbury to close the gaps in electrification beginning late in 1928. Despite the Great Depression the electrification project continued through 1933, completing the retrofit of the New York Terminal for AC traction and finishing catenary work to complete the network to Wilmington and Paoli. Understanding that Wilmington would not be a suitable southern terminal for electrification, catenary was pushed south to Washington DC including Potomac Yard, financed by a $70 million loan secured from depression era federal recovery programs. Beginning in January of 1934, various reports say up to 20,000 men went to work, comprising of furloughed railroad employees and new hires in the electrical / construction trades to complete the electrification of the New York – Washington DC main line, which opened for business on February 10th 1935. As a result of the success on the north-south “corridor” the PRR sought to complete electrification from the eastern seaboard west to the Harrisburg terminal including all associated freight and passenger main lines. Work commenced on the Low Grade from Morrisville to Enola, the main line from Paoli to Harrisburg, the Columbia Branch and Port Road. Completed in 1938 the entire electrification created a powerful conduit that put the railroad in an excellent position to handle the impending pressure of wartime traffic demands.

View looking east at the western limits of the Paoli interlocking plant. Number 2 and 3 track mains (center tracks) are basically stub end sidings here used occasionaly for track and maintenance equipment. The surviving infrastructure of the electrification reflects various generations of expansion including the massive singnal bridge, tubular trolley poles and the sub-station. This would have been some of the western most electrified trackage until the 1938 expansion to Harrisburg.  Note: This photograph was taken with Amtrak permission under watchman protection, the author does not condone any type of trespassing on railroad or private property. 

View looking east at the western limits of the Paoli interlocking plant. Number 2 and 3 track mains (center tracks) are basically stub end sidings here used occasionaly for track and maintenance equipment. The surviving infrastructure of the electrification reflects various generations of expansion including the massive singnal bridge, tubular trolley poles and the sub-station. This would have been some of the western most electrified trackage until the 1938 expansion to Harrisburg. Note: This photograph was taken with Amtrak permission under watchman protection, the author does not condone any type of trespassing on railroad or private property. 

The electrified infrastructure of the PRR Main Line has remained visibly the same over the ensuing decades despite modifications and renewal. Surviving the Pennsylvania Railroad, Penn Central, Conrail and Amtrak the sub-stations, tubular catenary poles and surviving interlocking towers remain along with many original station buildings preserving the character of the Main Line, a name synonymous not only with the railroad but towns along the route to Paoli. As Amtrak continues to renew their electric traction system the original details of the 1915 electrification, now part of the successful Keystone Corridor could be on borrowed time. There are plans being developed that would call for a total replacement of the 1915 era catenary system. The construction of larger modern support towers similar to those found on the Northeast Corridor will allow Amtrak to move feeder and transmission lines to the railroad right of way much like later phases of electrification did. For now while you ride the Paoli Local or one of Amtrak’s Keystone Service trains take note of the historical infrastructure that survives, that infrastructure around you was part of the one the most ambitious and successful railroad electrification projects in the world!