is can be operat- of course the ed independ- double line of ently of the cables that run others, or all side by side may be worked through the at the same time. The trenches; while one of these ca- two cables of the same sec- bles is working tion constitute the other is the double held as an aux-… … Fig l.-OPERATING MACHINERY OF TENTH AVENUE CABLE RAILWAY, NEW YORK CITY.-LOOKING TOWARD THE REAR, ) 1886 SCIENTIFIC AMERICAN, INC
