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and curves the strain is greater, requiring | foot greater depths than tabulated. The hole should be dug large enough to allow the pole to be dropped straight in without forcing it. Poles less than 45 feet in length are raised as shown in Fig. 66. This generally requires about 6 men, 4 of whom are provided with pike poles m, n, r, and s, that is, wooden poles from 8 to 14 feet long terminating
FIG. 66.—Method of Raising a Telephone Pole
in sharp iron points. The 4 men are distributed around the telephone pole which is placed with its butt projecting over the hole dug for it, and, by sticking their pikes in the pole and pushing, raise it to an upright position in the hole. The fifth man a, standing at the hole, guides the butt of the pole in the proper direction, while the sixth man C, with a heavy pole terminating in a U-shaped iron prong called the dead man, steadies the pole as it is being raised. Poles over 45 feet long are raised by means of a tripod-derrick erected over the hole.
The pole must be given its proper position in the hole before the earth is packed around it. In straight lines the pole must be placed perpendicular; at curves, it should be inclined slightly outward to compensate for the pull of the wires. The poles must be turned so that the gains for the crossarms on consecutive poles come on alternate sides; this will lessen the•number of cross-arms liable to be pulled off in case of a pole breaking. On straight lines the gains should be perpendicular to the line, and on curves they should be set radially. While the pole is held in its proper position the open space in the hole is filled in by means of one shovel, the earth being packed solidly around the pole by the simultaneous use of three tampers. Coarse earth or gravel should preferably be used at the top of the hole. When the ground is sandy or marshy a 6- or 8-inch grouting composed of 1 part Portland cement and 2 parts of sand mixedi with broken stone may well be used as an artificial foundation.
Side Strains on Poles at curves and corners must he counterbalanced by means of guys or braces. For guys, galvanized steel cable composed of not less than 7 strands, each 0.109 inch in diameter, must be used. One end of this should be fastened to an iron rod a, Fig. 67, about 8 feet long, which is threaded at the lower end and provided with a nut and washer s. This rod is passed through a
plank m and log c, the latter about 5 feet long and not less than 8 inches in diameter, and then buried
Fig. 67.—Method of Guying a Telephone Pole
6 feet under ground in such a position with respect to the pole that it will lie in the direction of the
Fig. 68.---Plan of Pole Line, Showing the Proper Position of a Guy and a Brace for Counterbalancing the Side Strains on a Pole
guy h, and make the plank and log serve as an anchor. The butt of the pole to be guyed should
be reinforced with 2 logs n and v similar to the one just mentioned, bolted to the butt of the pole as shown. The greater the distance between the butt of the pole and the anchor log c, the more
Fig. 69.—Details of Guying at Corners and Curves
serviceable the guy. In all cases the guy should halve the obtuse or outside angle formed by the poles. Thus in Fig. 68, the position of the pole h Causes the line to curve at this point. The strain of the wires from the poles cand e tends to pull the pole h toward the observer, and to counterbalance this the guy v should exert a tension in the opposite direction, along the bisector of the obtuse angle che. Some practical applications of guys at corners and curves are shown in Fig. 69 at A, B, and C. Head guys e, etc., are needed in case B from top
Fig. 70.-Use of a Guy Stub for Clearing Obstacles
of pole i to bottom of pole 2 and from top of pole 4 to bottom of pole 3. In case C, head guys e are used toward the middle of the curves as shown. The guy cable should be fastened to the pole by wrapping it twice around and then clamping it. Staples are used to prevent the guy from slipping on the pole.
Guy stubs serve to raise the cable when it is desired to clear obstacles. Thus, in Fig. 70 the guy stub a permits the pole guy m to be carried