13 July 1893
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Engineering News New York 13 July 1893 |
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TEN YEARS' RECORD OF THE BROOKLYN BRIDGE. The use of the bridge by the public in the ten years since it was opened has far surpassed all the calculations of engineers and others in advance of the completion of the structure. The wisdom of the men who widened the bridge so that room was afforded on the roadways for teams to pass each other, so that one slowly movlng load could not set the pace for all the trafflc, has been amply vindicated, and the policy which raised the height of the trusses so that cars of standard size could be used instead of the squatty ones it was at first proposed to use, has also been shown to be wise, and will be still further approved when electric elevated cars are run over the hridge from the elevated roads at either end without change. The grip in use upon the bridge cars, invented by one of the engineers, has been shown by the success attending its constant employment to be admirably adapted to the use to which it is put, the "life" of a cable being much more protracted than if the grip used with ordinary cable cars were employed. The system of switching cars has proved successful for a far greater traffic than was ever expected it would be called upon to handle, and by the improvements soon to be made with new platforms and tracks on both sides of them, the facilities for travel will be doubled, and twice as many passengers can be carried. In the ten years the receipts of the bridge from all sources have been about $10,000,000. Of this about one-half has been spent in maintenance and the other half in improvements. The original cost of the structure was $15,000,000, and the total cost up to the present time about $20,000,000. There have been a total of about 280,000,000 passengers carried in the cars since the railroad was put in operation, the number increasing from 8,000,000 in 1884 to over 40,000,000 last year. The car-fare was five cents at first, but was reduced to half this sum a few years ago. Foot passengers were originally charged a cent, and later one-fifth of a cent, but in 1891 the promenade was made free. Before that time about 3,000,000 people walked over the structure each year, and it is supposed that the number has been greater since, although no record can be kept, making a total of about 40,000,000 who have walked across the bridge. The earnings of the roadway from tolls, now only one-half of what they formerly were, are about $80,000 a year. From car-fares over $1,250,000 was received last year. The bridge was begun in 1870, and was 13 years in construction. The towers are 278 ft. high, and rest on foundations buIlt upon caissons. The New York tower foundation is 78 ft. below high water, and the foundations of the Brooklyn tower 45 ft. The center of the brldge is 135 ft. above high water, and at the towers the height is 110 ft. The cables contain 5,296 wires, each 3,578 ft. long, and the cables are 16 ins. in diameter. They uphold 14,680 tons of permanent weight. The total length of the bridge, with extensions, is 6,537 ft., and the width 85 ft. The river-span is 1,596 ft., each land-span 930 ft., the New York approach 1,562 ft., and the Brooklyn approach 971, making the carriage-way 5,080 ft. long. - N. Y. "Evening Post." |