|
Philadelphia And Western Railroad
The Philadelphia and Western Railroad was a high-speed, third rail-equipped, commuter-hauling interurban electric railroad operating in the western suburbs of the U.S. city of Philadelphia, Pennsylvania. It is now SEPTA's Norristown High Speed Line, though the Strafford spur has been abandoned. Part of the abandoned line within Radnor Township is now the Radnor Trail, a multi-use path or rail trail. Lines The current line runs from 69th Street Terminal just west of the Philadelphia city line, west and north to Norristown, splitting from the original main line at Villanova Junction. Formerly, the P&W's main line went west to a terminus just east of Sugartown Road in Strafford, then later, another further, on an extension providing transfer to the PRR Strafford station and a transfer track for freight trains. The Strafford Branch was abandoned in 1956; today, the Radnor Trail uses its old right-of-way from Radnor-Chester Road to Old Sugartown Road. Up until 1951, the P&W tra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allentown, Pennsylvania
Allentown (Pennsylvania Dutch language, Pennsylvania Dutch: ''Allenschteddel'', ''Allenschtadt'', or ''Ellsdaun'') is a city in Lehigh County, Pennsylvania, Lehigh County, Pennsylvania. The city has a population of 125,845 as of the 2020 United States census, 2020 census. It is the fastest-growing major city in Pennsylvania and the state's third largest city, behind Philadelphia and Pittsburgh. It is the largest city in both Lehigh County and the Lehigh Valley, which had a population of 861,899 and was the 68th most populous Metropolitan statistical area, metropolitan area in the U.S. as of 2020. Allentown was founded in 1762 and is the county seat of Lehigh County. Located on the Lehigh River, a tributary of the Delaware River, Allentown is the largest of three adjacent cities, along with Bethlehem, Pennsylvania, Bethlehem and Easton, Pennsylvania, Easton, in Lehigh and Northampton County, Pennsylvania, Northampton counties that form the Lehigh Valley region of eastern Pennsylv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soil
Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former term specifically to displaced soil. Soil consists of a solid phase of minerals and organic matter (the soil matrix), as well as a porous phase that holds gases (the soil atmosphere) and water (the soil solution). Accordingly, soil is a three-state system of solids, liquids, and gases. Soil is a product of several factors: the influence of climate, relief (elevation, orientation, and slope of terrain), organisms, and the soil's parent materials (original minerals) interacting over time. It continually undergoes development by way of numerous physical, chemical and biological processes, which include weathering with associated erosion. Given its complexity and strong internal connectedness, soil ecologists regard soil as an ecosystem. Most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Single Track (rail)
A single-track railway is a railway where trains traveling in both directions share the same track. Single track is usually found on lesser-used rail lines, often branch lines, where the level of traffic is not high enough to justify the cost of constructing and maintaining a second track. Advantages and disadvantages Single track is significantly cheaper to build and maintain, but has operational and safety disadvantages. For example, a single-track line that takes 15 minutes to travel through would have capacity for only two trains per hour in each direction safely. By contrast, a double track with signal boxes four minutes apart can allow up to 15 trains per hour in each direction safely, provided all the trains travel at the same speed. This hindrance on the capacity of a single track may be partly overcome by making the track one-way on alternate days, if the single track is not used for public passenger transit. Long freight trains are a problem if the passing s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Block Signal
Railway signalling (), also called railroad signaling (), is a system used to control the movement of railway traffic. Trains move on fixed rails, making them uniquely susceptible to collision. This susceptibility is exacerbated by the enormous weight and inertia of a train, which makes it difficult to quickly stop when encountering an obstacle. In the UK, the Regulation of Railways Act 1889 introduced a series of requirements on matters such as the implementation of interlocked block signalling and other safety measures as a direct result of the Armagh rail disaster in that year. Most forms of train control involve movement authority being passed from those responsible for each section of a rail network (e.g. a signalman or stationmaster) to the train crew. The set of rules and the physical equipment used to accomplish this determine what is known as the ''method of working'' (UK), ''method of operation'' (US) or ''safeworking'' (Aus.). Not all these methods require the us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Track Ballast
Track ballast forms the trackbed upon which railroad ties (sleepers) are laid. It is packed between, below, and around the ties. It is used to bear the load from the railroad ties, to facilitate drainage of water, and also to keep down vegetation that might interfere with the track structure. Ballast also holds the track in place as the trains roll over it. A variety of materials have been used as track ballast, including crushed stone, washed gravel, bank run (unwashed) gravel, torpedo gravel (a mixture of coarse sand and small gravel), slag, chats, coal cinders, sand, and burnt clay. The term "ballast" comes from a nautical term for the stones used to stabilize a ship. Construction The appropriate thickness of a layer of track ballast depends on the size and spacing of the ties, the amount of traffic on the line, and various other factors. Track ballast should never be laid down less than thick, and high-speed railway lines may require ballast up to thick.Bell 2004, p. 39 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rock (geology)
In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition, and the way in which it is formed. Rocks form the Earth's outer solid layer, the crust, and most of its interior, except for the liquid outer core and pockets of magma in the asthenosphere. The study of rocks involves multiple subdisciplines of geology, including petrology and mineralogy. It may be limited to rocks found on Earth, or it may include planetary geology that studies the rocks of other celestial objects. Rocks are usually grouped into three main groups: igneous rocks, sedimentary rocks and metamorphic rocks. Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed. Sedimentary rocks are formed by diagenesis and lithification of sediments, which in turn are formed by the weathering, transport, and deposition of existing ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grade (slope)
The grade (also called slope, incline, gradient, mainfall, pitch or rise) of a physical feature, landform or constructed line refers to the tangent of the angle of that surface to the horizontal. It is a special case of the slope, where zero indicates horizontality. A larger number indicates higher or steeper degree of "tilt". Often slope is calculated as a ratio of "rise" to "run", or as a fraction ("rise over run") in which ''run'' is the horizontal distance (not the distance along the slope) and ''rise'' is the vertical distance. Slopes of existing physical features such as canyons and hillsides, stream and river banks and beds are often described as grades, but typically grades are used for human-made surfaces such as roads, landscape grading, roof pitches, railroads, aqueducts, and pedestrian or bicycle routes. The grade may refer to the longitudinal slope or the perpendicular cross slope. Nomenclature There are several ways to express slope: # as an ''angle'' of inc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Level Crossing
A level crossing is an intersection where a railway line crosses a road, Trail, path, or (in rare situations) airport runway, at the same level, as opposed to the railway line crossing over or under using an Overpass#Railway, overpass or tunnel. The term also applies when a light rail line with separate Right-of-way (railroad), right-of-way or reserved track crosses a road in the same fashion. Other names include railway level crossing, railway crossing (chiefly international), grade crossing or railroad crossing (chiefly American), road through railroad, criss-cross, train crossing, and RXR (abbreviated). There are more than 100,000 level crossings in Europe and more than 200,000 in North America. History The history of level crossings depends on the location, but often early level crossings had a Flagman (rail), flagman in a nearby booth who would, on the approach of a train, wave a red flag or lantern to stop all traffic and clear the tracks. Gated crossings bec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Double Track
A double-track railway usually involves running one track in each direction, compared to a single-track railway where trains in both directions share the same track. Overview In the earliest days of railways in the United Kingdom, most lines were built as double-track because of the difficulty of co-ordinating operations before the invention of the telegraph. The lines also tended to be busy enough to be beyond the capacity of a single track. In the early days the Board of Trade did not consider any single-track railway line to be complete. In the earliest days of railways in the United States most lines were built as single-track for reasons of cost, and very inefficient timetable working systems were used to prevent head-on collisions on single lines. This improved with the development of the telegraph and the train order system. Operation Handedness In any given country, rail traffic generally runs to one side of a double-track line, not always the same side a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swedeland, Pennsylvania
Swedeland is a small unincorporated community in Upper Merion Township, Montgomery County, Pennsylvania, United States, in the suburbs of Philadelphia. It was founded as "Matsunk" by Swedish settlers in 1710. The name was changed to Swedeland sometime in the late 19th century. History Situated along the Schuylkill River and the Matsunk Creek, the Swedish village was composed of about 19 homes. After the conquering of the Swedish colony by the Dutch, followed by English control, in 1664, a third generation settler with the New Sweden Colony named Peter Yocum the Third (1678–1753) established Swedeland. William Penn offered the Swedish and Finnish colonists land from his grant in this Upper Merion area. By the mid-19th century, Abraham Supplee operated a factory producing Kentucky Jean, employing some 25 hands. The extensive works of the Swede Iron Company were also here, consisting of two large furnaces and a railroad leading from the iron ore mines to the Schuylkill River. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
