. American telephone practice . passesinto the main portion of the support serving in lieu of the secondbolt. Another advantage of this type of clamp is that the Uo\\ Slo AMERICAN TELEPHONE PRACTICE. never need be taken entirely out, which prevents the separation andpossible loss of the clamping block and bolt. Where more than one or two cables are to be supported from apole, cable cross arms are often used, these being of angle iron con-struction, bolted to the pole as an ordinary cross arm and braced bycross-arm braces in some such manner as is shown in Fig. it is desired also to carr
. American telephone practice . passesinto the main portion of the support serving in lieu of the secondbolt. Another advantage of this type of clamp is that the Uo\\ Slo AMERICAN TELEPHONE PRACTICE. never need be taken entirely out, which prevents the separation andpossible loss of the clamping block and bolt. Where more than one or two cables are to be supported from apole, cable cross arms are often used, these being of angle iron con-struction, bolted to the pole as an ordinary cross arm and braced bycross-arm braces in some such manner as is shown in Fig. it is desired also to carry one or more bare wires, wooden crossarms may be secured within the angle iron arm as shown in thisFigure, on which wooden arm ordinary pins and insulators may besecured. The cable is suspended from the messenger wire in several dif-ferent ways. Sometimes it is suspended by binding it to the mes-senger wire by strong tarred marlin. The marlin is wrapped aroundboth cable and messenger wire, usually in two directions to give it. FIG. 593.—CROSS-ARM FOR MESSENGER SUPPORT. greater security. This method is still largely used by the WesternUnion Telegraph Company in supporting its cables. The method now most extensively used by telephone companiesin supporting aerial cable is by means of cable hangers adapted totightly encircle the cable sheath and provided with a hook to slipover the messenger wire. One of the best forms of cable hangeris that shown in Figure 594. This consists merely of a loop ofmarlin, to one end of which is attached a galvanized steel wirehook. The method of attaching this to the cable is clearly shown inthe figure. The marlin hanger has been much criticized on theground that it would subsequently rot and allow the cable to fall,and many forms of all metal hangers have been devised to take itsplace. Some of these involved the use of a zinc band which wasplaced around the cable and supported by the wire hook. They AERIAL CABLE CONSTRUCTION. 817 were very satisf
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