Page:Popular Science Monthly Volume 23.djvu/402

From Wikisource
Jump to navigation Jump to search
This page has been proofread, but needs to be validated.
388
THE POPULAR SCIENCE MONTHLY.

small part of the weight. Engineer Roebling says that the cables are strong enough to pull up the anchorages, but, as each of these weighs 60,000 tons, they probably will never be called upon to perform that feat.

The roadway on the approaches is 100 feet wide, on the spans 85 feet. The outside avenues are for vehicles, the next two are car-tracks, and a footway 16 feet wide occupies the middle. This latter is paved with asphalt as far as the anchorage, and is only three feet above the driveways. Here it rises by a flight of steps to a plank walk twelve feet above the driveways, from which a clear view over both sides of the bridge can be had. To prevent danger in case the brakes should fail to control a train coming down the incline of the roadway, the car-tracks are kept at the same level for the last 600 feet on each approach, which brings them out at about the level of the elevated roads. The cars are to be propelled by means of an endless wire rope, which will run between the rails of each track, over grooved wheels, set upright 2212 feet apart. Motion is communicated to the rope by two stationary engines located on the Brooklyn side. It is calculated that the cars can take 80,000 passengers across in an hour, that 50,000 more can cross on the promenade, while the driveways will accommodate nearly 1,500 vehicles an hour.

The roadway is lighted by 70 electric lights, set on posts upon the trusses that run between the car-tracks and carriage-ways.

The bridge, which had been fourteen years in building, was formally opened May 24, 1883. Up to April 1st there had been paid out on the work $14,429,003.25, and the expenses then remaining to be met will bring the cost up to nearly $16,000,000. In length of span the Brooklyn Bridge surpasses every other bridge in the world. The span of Roebling's Niagara suspension-bridge is 821 feet, a little more than half as great; the span of the suspension-bridge at Fribourg, built in 1832, the longest in Europe, is 870 feet; while Roebling's Cincinnati bridge, which has the second longest span in the world, measures 1,057 feet between the towers, or about two thirds the length of the East River span.

THE INDUSTRIAL POSITION OF WOMEN.

By EMILY BLACKWELL, M. D.

AMONG all the questions affecting women, and society through women, there is none more vital than that of their industrial position. It is conceded that women should work, but there is a great difference of opinion as to what their work is, and how they should do it. This difference of public opinion is not merely a matter of theory; it leads to very positive practical results, for the support of