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New Use for the Auto

A NEW departure in the development

of the automobile truck has been tried by the Bell Telephone Company with great success. Every one is familiar with the enormous winch wound around with lead piping which is laboriously unwound by muscular laborers for burial in the subway. The old process of pulling overhead and underground cables is entirely done away with by the use of the auto-truck. The truck is equipped with two winches, which, for underground work have a speed of 50 feet per minute and a pulling strength of 5,000 pounds, while in aërial work this is increased to 150 feet per minute with a pulling strength of 5,000 pounds.

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OLD METHOD OF PULLING CABLES. Laborious and tiresome. It required eight persons to operate each winch, which pulled but fifteen feet per minute.

the winches, may be varied according to conditions.

As an instance of the great saving in time and labor, it may be stated that, under the old-style hand-winch process, eight persons were required to operate

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F

Great Drawbridge Towed to

Place

By John G. Mueller

NOR the completion of the west branch of New York's great subway, which is now running from the Battery to the Harlem ship canal (commonly known as the Harlem river) at Kingsbridge-a distance of fourteen and one-quarter miles-it was found necessary to replace the old drawbridge at this point with a doubledecked structure specially designed to accommodate the subway train traffic, which near this point emerges from the tunnel and continues as elevated to the terminal.

The stupendous proposition-which was effectually carried out-was to lift this draw from between its approaches,

barges on the water end, and then pulled into position and anchored. This was done without disturbing traffic.

Both draws are 272 feet long, the old one weighing 1,200 tons and containing a steam operating outfit in the turret.

Four barges, having a combined capacity of 2,500 tons, were securely lashed in pairs, and loaded to the required height with suitable heavy blocking, as seen under the draw in the photo. These were then drawn into place at low tide, two on each side of the center bulkhead; partly submerged; and finally blocked close under the bridge. Then, with the rising tide, and emptying the barges simultaneously with a pair of powerful cen

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NEW DRAWBRIDGE TO REPLACE OLD STRUCTURE OVER HARLEM RIVER. Showing manner in which it was built on piles.

tow it one and one-quarter miles, and place it in a new position, repeating this operation in replacing it with the new structure. The old approaches, 100 and 112 feet long respectively, were first removed and replaced with the new approaches of the same length, weighing 300 and 400 tons. These were built close to and parallel to the old approaches, on railroad trucks on the shore end and

trifugal pumps, the draw was easily raised almost two feet above the approach level.

Now the journey began. With two tugs pulling, and two in the rear to control this unwieldy mass, it was successfully navigated around a difficult curve and deposited over its new position, in less than twenty-five minutes. The barges were then again gradually submerged un

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til the structure was accurately centered, when they were withdrawn to be used again.

One of the accompanying photographs shows the draw on its way. The end of the bulkhead from which it was taken is seen on the extreme right over the water.

OLD DRAWBRIDGE OVER HARLEM RIVER BEING REMOVED TO NEW SITE.
Rests on timber falsework carried by barges towed by tug.

The other photograph shows the new doubledecked draw whose superstructure supports. three tracks. The king post is 98 feet above mean water-level; it weighs 2,000 tons and is operated by electricity. As shown, it was built on piles in a position where it would not interfere with canal traffic, about seven-eighths of a mile from its future position. The spaces at each end were left open so as to enable the engineers to place the barges. This structure also was successfully moved at high tide, June 16, the whole operation being done in about twenty-five minutes from the time it left the piles until it was over its new position.

On account of the 800 tons more

weight, the clearance between the bulkhead center and bridge guide wheels was only four inches, necessitating quick, accurate work in lowering the bridge (by submerging barges) before the tide and current changed.

Although the Rapid Transit Commission, who undertook the work, had obtained a permit from the United States Government to close the canal for three days, it was actually closed only during the time that the structures were being moved.

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