. Water & sewage works . be poleswith the two lower globes omitted. Inthe parks and along the driveways a sin-gle 20-inch globe, with a To-watt 12i4-voItlamp is used. Altogether, there are 1,116five-ball poles lighting miles of streets,378 three-ball poles lighting miles, and137 one-ball poles lighting 3 miles ofstreet, making a total of 1,631 poles light-ing 25 miles of street. In the business district the system isfed from the underground mains placednear the curb line. The main feeders areplaced in vitrified clay ducts with the com-mercial feeders, and the branches are runin fibre
. Water & sewage works . be poleswith the two lower globes omitted. Inthe parks and along the driveways a sin-gle 20-inch globe, with a To-watt 12i4-voItlamp is used. Altogether, there are 1,116five-ball poles lighting miles of streets,378 three-ball poles lighting miles, and137 one-ball poles lighting 3 miles ofstreet, making a total of 1,631 poles light-ing 25 miles of street. In the business district the system isfed from the underground mains placednear the curb line. The main feeders areplaced in vitrified clay ducts with the com-mercial feeders, and the branches are runin fibre conduit cased with concrete. Anexception to this is made when the ductsrun under the walk where a basement isto be excavated. In these places steel con-duit is used, placed just beneath the side-walk. Manholes for transformers areplaced below the sidewalk at street cor-ners, about three blocks apart. Five, ten B>llchM ciulppcd >i 1th Overtokd Tllpplo and tUierae-CurroDt IiiTen«*Tlin»- eO,(UO Volt Bum*. DIAGRAM of connections on special control board. the lamps placed in a triangle perpendicu-lar to the sidewalk, with a 16-inch globeat the top, two 14-inch below and two 12-inch globes, turned downward, at the baseof the triangle. All the globes have alight sand-blast finish. This design givesa beautiful festoon of decorative lightsalong the sidewalks, and at the same timesecures a uniform illumination on allparts of the street. The intensity on thesidewalk carries from to foot-candles, and at the center of the streetfrom to foot-candles. This il-lumination, which is ample, is producedby using 50-watt tungsten lamps fed fromthe small transformers in the pole baseat a pressure of S volts. This type oflamp was designed by the General Elec-tric Company especially for the lightingdepartment and has proved so satisfac-tory that it has since been made standardby that company. The average life of thislamp has proved to be over 2,000 residence distric
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectsewerage, bookyear191
