ble. Longer poles usually vary by 5 feet upward to 70 feet and are buried from 6 to 8 feet in the earth. The circumference at the top of the pole and at 6 feet from the butt must be considered in selecting poles. These dimensions should be proportional to the length of the pole and should approximate those given in the following table for poles from 20 to 70 feet long:

The top of each pole should be slightly pointed as in Fig. 65 and then painted to enable it to shed water. A number of gains n should be cut in the pole, corresponding to the number of cross-arms to be used. The center of the first gain should be 10 inches from the top of the pole, and the center of each subsequent cut should be 24 inches below that of the preceding one. The gains should each be 3 inches wide and inch deep, true and square with the axis of the pole so that the

cross-arms when fitted in them will be at right angles to the pole in all directions. Each gain should be bored for one §-inch bolt, directly through the center of the pole and at right angles to the gain, and should be painted to protect it from moisture. A paint well adapted for the top and gains of a pole is Prince's metallic paint, mixed in the proportion of 7 pounds of the dry paint to

FIG. 65. Telephone Pole Top Equipped with Cross Arms, Braces, Pins, and Insulators

I gallon of linseed oil. Two thick coats of this paint should be applied.

In Setting Poles a hole for each one is dug in the ground to a depth of 5 to 8 feet, depending on the height of the pole and the condition of the ground. When the ground is of normal consistency, the depths noted in the table just given are considered proper for straight lines; on corners

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 I part Portland cement and 2 parts of sand mixed with broken stone may well be used as an artificial foundation.

Side Strains on Poles at curves and corners must be 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