. Public works . f the city to the state walks and curbs were constructed at the samelime, and in the latter was placed the l>^-inch fibre con-duit through which the insulated conductor was to bedrawn. The electroliers were made of gas-pipes with a cast-ironbase which was anchored to a concrete base, 18 inchessquare and 18 inches deep and moulded at the same timethe curbs were made, by four 34-inch bolts 16 inches inlength. The top length of pipe was bent to a radius of12 inches and to the end of this a fluted reflector wasscrewed. The lamp proper was ft. above the curb
. Public works . f the city to the state walks and curbs were constructed at the samelime, and in the latter was placed the l>^-inch fibre con-duit through which the insulated conductor was to bedrawn. The electroliers were made of gas-pipes with a cast-ironbase which was anchored to a concrete base, 18 inchessquare and 18 inches deep and moulded at the same timethe curbs were made, by four 34-inch bolts 16 inches inlength. The top length of pipe was bent to a radius of12 inches and to the end of this a fluted reflector wasscrewed. The lamp proper was ft. above the was found to be too short a distance, and a better post was designed and used in the later installations ofthis character. Fifty-two standards were used on thisstreet, one being placed on each street corner and oneon each side midway between. The fibre conduit was placed at the time of construct-ing the curbs. Three inches of concrete was first placedin the curb forms and upon this the conduit was carefully. LAMP STANDARDS USED IN HELENA. laid with well connected joints, a waterproof compoundlieing used for this purpose. Connections were madewith the bases of the posts with a 54 bend of 15-inchouter radius. In laying the conduit across the street, itwas placed in concrete for better protection. Threeinches of concrete was first placed in the trench and theconduit was then laid, after which four inches of concretewas ])laced over the conduit. This was placed at sucha depth as not to interfere with any future street paving. The wiring was to be connected with that of the arclighting system, which necessarily carried a very highvoltage, and the conductor used was a No. 6 B. & copper wire, rubber insulated for 3000 volts, whichconductor was enclosed in a lead tube for a moisture[jroof underground conductor. We had no little troublewith this installation during the first six months as, insome unexplainable manner, it became short circuited andruptured the lead sheathin
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Keywords: ., bookcentury1800, bookdecade1890, bookidpublicworks3, bookyear1896
