loosely on the pulley and receives adhesion by tightening pulleys which enable the working rope to be set in motion or stopped, without stopping the engine. The engine has a 12 inch cylinder with 24 inches stroke, carries from 60-75 lbs. of steam and makes about 70 revolutions per minute. This corresponds to a speed of 4 feet per second of the traveling rope, which therefore requires 14 minutes for a trip from anchorage to anchorage. The whole machinery, described above, is double; each set doing the work of carrying wire for two cables. The driving power is derived from the same steam engine. During its passage from anchorage to anchorage, the working rope is supported on the towers and on each cradle by properly placed sheaves. In close connection with the working rope is the "traveling sheave."

This is a light wooden wheel 5 feet in diameter with a grooved rim of zinc, in which the wire hangs, while traveling It is secured to the traveler by an iron, bent in the shape of a goose

across.

neck, so as to allow free passage of the rope over all supporting sheaves. An iron rod with a weight at the end, fastened to the hub of the wheel, keeps it in vertical position and prevents it being upset by the wind. Each working rope carries two traveling sheaves placed so, that one is at the New York anchorage,

while the other is at the Brooklyn anchorage. When, for instance, the left sheave carries a wire from Brooklyn to New York, the right one moves empty in opposite direction. When the latter arrives at the Brooklyn anchorage, the driving wheel is stopped, a wire placed on the same, and the motion of the working rope is reversed.

Other appliances in the service of stretching wire are the wire drums. There are altogether 32 drums, 8 for each cable, the chief object of which is to serve as reservoirs of wire ready for being worked into strands. Each drum is 8' 2" in diameter, 15" wide and can hold about 50,000 feet wire, which is enough for six to seven trips of the traveling sheave. It is provided with a brake by means of which the sag in the running wire can be regulated. necessary that the wire is wound tight on the drum, else the brake is ineffective. The wire ring therefore is placed first on a smaller wheel (Fig. 13), from which it is unwound on the large drum under

It is

Fig.13

2x 4"

Scale 1 inch-3 feet

considerable tension achieved by the brake R on the arms of the small drum. Small movable flanges (Fig. 14) admit

Fig.14

B

A

putting the wire on and hold it afterwards in place.

2. Cradles and Cradle Ropes.The cradles are necessary for various