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Towers

After the caissons were completed, piers were constructed on top of each of them upon which masonry towers would be built. The towers' construction was a complex process that took four years. Since the masonry blocks were heavy, the builders transported them to the base of the towers using a pulley system with a continuous 1.5-inch (3.8 cm) -diameter steel wire rope, operated by steam engines at ground level. The blocks were then carried up on a timber track alongside each tower and maneuvered into the proper position using a derrick atop the towers. The blocks sometimes vibrated the ropes because of their weight, but only once did a block fall.

Construction on the suspension towers started in mid-1872, and by the time work was halted for the winter in late 1872, parts of each tower had already been built. By mid-1873, there was substantial progress on the towers' construction. The Brooklyn side's tower had reached a height of 164 feet (50 m) above mean high water (MHW), while the tower on the Manhattan side had reached 88 feet (27 m) above MHW. The arches of the Brooklyn tower were completed by August 1874. The tower was substantially finished by December 1874 with the erection of saddle plates for the main cables at the top of the tower. However, the ornamentation on the Brooklyn tower could not be completed until the Manhattan tower was finished. The last stone on the Brooklyn tower was raised in June 1875 and the Manhattan tower was completed in July 1876. The saddle plates atop both towers were also raised in July 1876. The work was dangerous: by 1876, three workers had died having fallen from the towers, while nine other workers were killed in other accidents.

In 1875, while the towers were being constructed, the project had depleted its original $5 million budget. Two bridge commissioners, one each from Brooklyn and Manhattan, petitioned New York state lawmakers to allot another $8 million for construction. Ultimately, the legislators passed a law authorizing the allotment with the condition that the cities would buy the stock of Brooklyn Bridge's private stockholders.

Work proceeded concurrently on the anchorages on each side. The Brooklyn anchorage broke ground in January 1873 and was subsequently substantially completed in August 1875. The Manhattan anchorage was built in less time, having started in May 1875, it was mostly completed in July 1876. The anchorages could not be fully completed until the main cables were spun, at which point another 6 feet (1.8 m) would be added to the height of each 80-foot (24 m) anchorage.