An overhead power line is an electric power transmission line suspended by towers or utility poles. Since most of the insulation is provided by air, overhead power lines are generally the lowest-cost method of transmission for large quantities of electric energy. Towers for support of the lines are made of wood (as-grown or laminated), steel (either lattice structures or tubular poles), concrete, aluminum, and occasionally reinforced plastics. The bare wire conductors on the line are generally made of aluminum (either plain or reinforced with steel, or sometimes composite materials), though some copper wires are used in medium-voltage distribution and low-voltage connections to customer premises. A major goal of overhead power line design is to maintain adequate clearance between energized conductors and the ground so as to prevent dangerous contact with the line. Today overhead lines are routinely operated at voltages exceeding 765,000 volts between conductors, with even higher voltages possible in some cases.
Read more about Overhead Power Line: Classification By Operating Voltage, Structures, Insulators, Conductors, Compact Transmission Lines, Low Voltage, Train Power, Further Applications, Use of Area Under Overhead Power Lines, History
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“There’s something wonderfully exciting about the quiet sing song of an aeroplane overhead with all the guns in creation lighting out at it, and searchlights feeling their way across the sky like antennae, and the earth shaking snort of the bombs and the whimper of shrapnel pieces when they come down to patter on the roof.”
—John Dos Passos (1896–1970)
“Here far from the city we make our roadside stand
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And give us the life of the moving-pictures’ promise
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—Robert Frost (1874–1963)
“The modern picture of The Artist began to form: The poor, but free spirit, plebeian but aspiring only to be classless, to cut himself forever free from the bonds of the greedy bourgeoisie, to be whatever the fat burghers feared most, to cross the line wherever they drew it, to look at the world in a way they couldn’t see, to be high, live low, stay young forever—in short, to be the bohemian.”
—Tom Wolfe (b. 1931)