94 METHODS OF OOMMVNWATTON FOR FOREST PROTECTION 



possible. This gives an appearance of neatness and simplifies tracing out the wires 

 when hunting for trouble. There should be no knots or spirals in the wiring (this 

 does not mean joints and splices) between the protector and the line or ground rod. 

 The line should 'be kept at least 1 ft. away from the overhanging eaves if the roof 

 is of sheet-iron. 'Wet and! damp localities should be avoided for inside wires. 



The telephone should be connected to the protector by means of No. 19 B. & S. 

 rubber-covered and braided, single or twisted-pair copper wire. However, if this 

 wire is not available, the heavier insulated outside wire may be used, although it 

 is not so cheap. The wire inside the building should be' fastened to the wall with 

 insulated tacks, milonite nails, or approved cleats. Uninsulated' tacks or staples 

 should not be used. No joint in insulated wire should touch an adjacent joint in 

 another insulated wire, even though both are taped. 



(a) Protection from pipes. Wherever practicable, wires should be placed above 

 all pipes or other conducting material. When a crossing is necessary the wire 

 should be protected by two wrappings of insulated tape, the latter extending at 

 least 1 in. each side of the pipe or conducting material. 



(fr) Separation from light and power lines. When it is necessary to cross an 

 electric-light or power wire in the building there must be a separation of at least 

 6 in., unless tne telephone wires are incased in a circular loom or porcelain conduit. 

 When so incased the conduit should project at least 6 in. on each side of the electric- 

 light or power wire and be firmly secured against slipping. 



Section 75 Lookout-station Telephone Sets 



The 133'6-J telephone, special forest protection type, contains a 2600-ohm unbiased 

 ringer and condenser. The 1336-K telephone contains a 1600-ohm unbiased ringer 

 and cond'enser. 



An iron-box telephone set outdoors should be mounted on a post in preference 

 to a tree or topped tree. The iron case of the box should be grounded by wrapping 

 a wire under the head of one of the mounting bolts when the latter is screwed in 

 and then running it to the ground rod (Fig. 49.) A switch and protector mounting- 

 box should be atfached' to the post. The line wire should be properly dead-ended on 

 a bracket and insulator located on top of the post and extended to the switch by 

 means of No. 14 B. & S. gauge, rubber-covered, braided and weather-proofed, copper 

 wire. This wire should then extend from the opposite side of the switch to the 

 line terminal of the protector and from there to the proper terminal in the telephone 

 set, through the hole in the latter provided for the purpose. The same kind of wire 

 should extend from the ground Tod to the ground terminal of the protector and to 

 the proper terminal in the iron-box telephone, through the hole provided in the 

 latter. 



If this set is employed on a metallic circuit, a double-pole, single-throw switch 

 should be used (Fig. 49). From each of the line wires an insulated copper wire 

 should extend to a switch, and' from the opposite terminal to its proper terminal 

 on the protector, and thence into the iron-box set. The latter is grounded from 

 the mounting bolt, while another 'wire runs from the ground terminal of the protector 

 to the ground rod. 



Installations of this character may be placed on lookout points where there is 

 nothing but rock. The post may be bolted to the rocks and the ground rod located 

 wherever .a suitable place can be found, even though it is a considerable distance 

 away. In this case the wire to the ground rod is run in the same manner as line 

 wire is run. Metal brackets and fixtures may be used to support the line wire along 

 the side of the rock, with extension bolts if required. 



