The Brooklyn Bridge

Caissons

The construction of the Brooklyn Bridge began in 1870 with the creation of two massive caissons. These inverted wooden boxes were sunk to the riverbed to form the foundation for the bridge towers. Working conditions inside the caissons were harsh, with workers, known as sand hogs, facing extreme air pressure and poor air circulation. This led to many workers suffering from decompression sickness, also known as the bends. Washington Roebling, who oversaw the project, was himself paralyzed by the condition and had to supervise the construction from afar.

The air pressure inside the caisson was the same as the water outside and there was no light. Workers would have to dig and break up large boulders to continue to make the caisson sink lower. It was miserable work. It was dark and hot and you had to work by candlelight and the air circulation was poor.

--- Gary Arndt

Roebling's wife, Emily, took over many of his duties, passing along his instructions to the engineers on site. Once the caissons reached their desired depths, they were filled with bricks and concrete, forming the base for the bridge towers 1.

   

Towers

The towers of the Brooklyn Bridge, standing at 278 feet tall, were constructed from granite, limestone, and cement. These towers, featuring a neo-Gothic arch design, took four years to complete and were the most time-consuming part of the project. Originally, John Roebling had envisioned the towers to resemble Egyptian tombs, but the final design was altered.

The towers are reached 278ft, or 85 meters tall. They're made out of granite, limestone and cement. The towers were the most time consuming part of the project, having taken four years to build.

--- Gary Arndt

The completion of the towers marked a significant milestone in the construction of the bridge, setting the stage for the installation of the steel cables 1.

   

Cables

The Brooklyn Bridge was the first to use galvanized steel cables, a significant innovation in bridge engineering. Each of the four main cables, measuring 15.75 inches in diameter, consisted of 19 strands, with each strand containing 273 wires. This bundled wire technique was a groundbreaking method at the time.

The cables, as I mentioned before, were made out of steel, specifically galvanized steel, which was a first for suspension bridges.

--- Gary Arndt

The bridge opened on May 24, 1883, and quickly became an engineering marvel of its era. Despite initial doubts about its structural integrity, the bridge proved its strength and durability, even hosting a parade of 21 elephants led by P.T. Barnum to demonstrate its stability 2.