Sunday, May 24, 2020
Follow the evolution of the road from path to pavement
The first indications of constructed roads date from about 4000 BC and consist of stone-paved streets at Ur in modern-day Iraq and timber roads preserved in a swamp in Glastonbury, England. Late 1800s Road Builders The road builders of the late 1800s depended solely on stone, gravel, and sand for construction. Water would be used as a binder to give some unity to the road surface. John Metcalfe, a Scot born in 1717, built about 180 miles of roads in Yorkshire, England (even though he was blind). His well-drained roads were built with three layers: large stones; excavated road material; and a layer of gravel. Modern tarred roads were the result of the work of two Scottish engineers, Thomas Telford and John Loudon McAdam. Telford designed the system of raising the foundation of the road in the center to act as a drain for water. Thomas Telford (born 1757) improved the method of building roads with broken stones by analyzing stone thickness, road traffic, road alignment, and gradient slopes. Eventually, his design became the norm for all roads everywhere. John Loudon McAdam (born 1756) designed roads using broken stones laid in symmetrical, tight patterns and covered with small stones to create a hard surface. McAdams design, called macadam roads, provided the greatest advancement in road construction. Asphalt Roads Today, 96% of all paved roads and streets in the U.S. - almost two million miles - are surfaced with asphalt. Almost all paving asphalt used today is obtained by processing crude oils. After everything of value is removed, the leftovers are made into asphalt cement for pavement. Man-made asphalt consists of compounds of hydrogen and carbon with minor proportions of nitrogen, sulfur, and oxygen. Natural forming asphalt, or brea, also contains mineral deposits. The first road use of asphalt occurred in 1824 when asphalt blocks were placed on the Champs-Ãâ°lysà ©es in Paris. Modern road asphalt was the work of Belgian immigrant Edward de Smedt at Columbia University in New York City. By 1872, De Smedt had engineered a modern, well-graded, maximum-density asphalt. The first uses of this road asphalt were in Battery Park and on Fifth Avenue in New York City in 1872 and on Pennsylvania Avenue, Washington D.C., in 1877. History of Parking Meters Carlton Cole Magee invented the first parking meter in 1932 in response to the growing problem of parking congestion. He patented it in 1935 (US patent #2,118,318) and started the Magee-Hale Park-O-Meter Company to manufacturer his parking meters. These early parking meters were produced at factories in Oklahoma City and Tulsa, Oklahoma. The first was installed in 1935 in Oklahoma City. The meters were sometimes met with resistance from citizen groups; vigilantes from Alabama and Texas attempted to destroy the meters en masse. The name Magee-Hale Park-O-Meter Company was later changed to the P.O.M. company, a trademarked name made from the initials of Park-O-Meter. In 1992, POM began marketing and selling the first fully electronic parking meter, the patented APM Advanced Parking Meter, with features such as a free-fall coin chute and a choice of solar or battery power. By definition, traffic control is the supervision of the movement of people, goods, or vehicles to ensure efficiency and safety. For example, in 1935, England established the first 30 MPH speed limit for town and village roads. Rules are one method of controlling traffic, however, many inventions are used to support traffic control. For example, in 1994, William Hartman received a patent for a method and apparatus for painting highway markings or lines. Perhaps the best known of all inventions related to traffic control is traffic lights. Traffic Lights The worlds first traffic lights were installed near Londons House of Commons (intersection of George and Bridge Streets) in 1868. They were invented by J.P. Knight. Among the many early traffic signals or lights created the following are noted: Earnest Sirrine of Chicago, Illinois patented (976,939) perhaps the first automatic street traffic system in 1910. Sirrines system used the nonilluminated words stop and proceed.Lester Wire of Salt Lake City, Utah invented (unpatented) electric traffic lights in 1912 that used red and green lights.James Hoge patented (1,251,666) manually controlled traffic lights in 1913, which were installed in Cleveland, Ohio a year later by the American Traffic Signal Company. Hoges electric-powered lights used the illuminated words stop and move.William Ghiglieri of San Francisco, California patented (1,224,632) perhaps the first automatic traffic signal using colored lights (red and green) in 1917. Ghiglieris traffic signal had the option of being either manual or automatic.Around 1920, William Potts a Detroit policeman invented (unpatented) several automatic electric traffic light systems including an overhanging four-way, red, green, and yellow light system. The first to use a yellow light.Gar rett Morgan received a patent for an inexpensive to produce manual traffic signal in 1923. Dont Walk Signs On February 5, 1952, the first Dont Walk automatic signs were installed in New York City.
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