Trains, Boats & Planes | 16 September 2016Towers & Interlocking Railroad Signals Share article facebook twitter google pinterest America’s rail network is one of the most underrated technologies in the country, and it has a fascinating history in its use of railroad signals. Brian Solomon’s book Classic Railroad Signals explores the usage of these signals throughout history and in present day. Check out the following towers and interlocking signals excerpted from Solomon’s book, some of the most essential and advanced signals used on the rail. Pretty cool stuff! A New Haven Railroad Alco PA approaches Boston’s South Station on March 11, 1956. This terminal’s large electropneumatic interlocking and lower-quadrant semaphore signaling was installed under the able administration of US&S signaling genius J.P Coleman in 1897–1898. Some of the signals remained in service until South Station was reconfigured in the mid-1980s. Jim Shaughnessy A Central Railroad of New Jersey Budd-built rail diesel car departs Jersey City on November29, 1964. Fifty years earlier, CNJrebuilt its Jersey City terminal with a state-of-the-art Union Switch & Signal electropneumaticsystem. Richard Zmijewski Against a backdrop of the Manhattan skyline, Reading’s Crusader departs Central Railroad of New Jersey’s Jersey City terminal for Philadelphia. CNJ’s complex plant featured three interlocking towers, which controlled a nine-track throat with four ladder arrangements (two in each direction) that allowed parallel movements for trains to reach platforms. Three-position, upper quadrant electropneumatic semaphores governed train movements. Richard Jay Solomon Three-arm, upper-quadrant semaphores mounted on tall bracket post gantries were a common feature of interlocking signals on New York Central’s Big Four route. These signals at Quincy, Ohio, survived into the Conrail era and were photographed with the setting sun on March 15, 1980. Notice that the blades in the third tiers (used to display slow-speed and restricting indications) use a slightly shorter blade. John F. Bjorklund, courtesy of the Center for Railroad Photography & Art (www.railphoto-art.org). Canadian Pacific freight 413 received an “Approach Medium”—yellow over green over red—as it exited the siding at CPF 485 in Schenectady, New York, on April 16, 2005. CP’s Delaware & Hudson routes had been largely equipped with General Railway Signal searchlights, but since 2005, most of this traditional hardware has been replaced with modern color lights. Patrick Yough This mechanical semaphore at 75th Street Tower, Chicago, provides a nice silhouette against a January 2, 1995, morning sky. The 132-lever Saxby & Farmer mechanical interlocking was originally installed in July 1908, by the Federal Signal Company of Troy, New York. Its location at 75th Street is where Chicago Terminal Transfer Railroad crossed Baltimore & Ohio Chicago Terminal, Belt Railway of Chicago, Wabash, and Pennsylvania Railroad’s Panhandle line. This junction was completely re-signaled 89 years later by which time it was among the last mechanical plants in the Chicago area. Brian Solomon These mechanical upper-quadrant semaphores at Brighton Park in Chicago were built to the Loree–Patenall patent of 1903. The non-interlocked level crossing required all trains to stop before being signaled through the junction by semaphore indication. It was among the last crossings in the Chicago area protected by mechanical semaphores, and was finally upgraded in 2007 with modern systems and color light signals. Brian Solomon Westward helpers approach CSX’s Q Tower at Hardman, West Virginia. Line-side interlocking towers survived on CSX’s former Baltimore & Ohio lines decades longer than on other American mainlines. By the time of this image the tower had a reduced role from its heyday and many of the old manual levers were out of service. Brian Solomon uy from an Online Retailer US: UK: Explore the history, quirks, and stories behind signals with gorgeous period and contemporary photography. Railroad signals are the link between the steam era and modern railroading. Designed for reliability and durability, signals can survive for decades. In fact, old semaphores installed during the early years of the twentieth century were still in service during the 1990s, protecting trains that were running with the latest modern diesels. Even searchlight-style signals that were the epitome of 1940s railroading continue to work today. Though standards were introduced in the early twentieth century, interpretation varied greatly among railroads, so even major railroads have individualized signals. Some, such as the Pennsylvania Railroad, were noted for their distinctive signaling hardware. Others lines became known for their peculiarities in practice. Classic Railroad Signals examines how different railroads developed specific hardware to serve their unique needs, in the process tracing the lineage of various types of hardware and highlighting how and where they were used. From nineteenth-century mechanical signals to disc signals, upper- and lower-quadrant semaphores, three-light electric signals, searchlight-style targets, positional lights, and color-position light hardware, author Brian Solomon covers nearly every conceivable piece of North American signaling hardware, even the virtually extinct wig wag that was once standard in California and Wisconsin. Gorgeous period and contemporary photography shows signals and trains from around North America. Classic Railroad Signals should be next to Railroad Signaling on every railroad fan’s bookshelf. 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