Washington Roebling was the engineer in charge of the Brooklyn Bridge in New York. In 1871 he went into a caisson to see how his men worked there. He came out very sick. For the rest of his life, he could not move his body well.
A caisson is a very big box under a river. It is full of air with high pressure. The air keeps the water out, and men dig at the bottom. They build the parts of the bridge that stand in the river.
Workers often got sick in caissons. They called it caisson disease. Today we call it decompression sickness. When the air pressure goes down too fast, small bubbles form in the blood. People have pain in their arms and legs, and they cannot breathe well. Some people cannot move. In the 1870s, nobody knew the reason for this sickness.
Roebling started work on the bridge in May 1870. The bridge was 1,600 feet long, and it connected Manhattan and Brooklyn. His father, John A. Roebling, planned the bridge, but he died early in the work.
At Brooklyn, a doctor called Andrew H. Smith took care of the men. He saw 86 sick workers. He gave them medicine, but he could not stop the sickness because he did not know the cause.
Roebling was worried because many men got hurt or died. The plan was to dig 100 feet down, to the rock. But he stopped at 78 feet and built the Manhattan tower on sand.
In May 1883, a newspaper wrote about Mrs. Roebling. Some men from factories came to New York to talk to Colonel Roebling about work on the bridge. They were very surprised when Mrs. Roebling sat down with them. She knew a lot about engineering, and she helped them with their problems. The bridge opened in the same month.
A man called Abram S. Hewitt gave a speech about the bridge for the city of New York. He said that people will always remember the name of Mrs. Emily Warren Roebling.
A French scientist, Paul Bert, found the reason for the sickness. It came when the pressure went down too fast. He said workers must come up slowly. Doctors still use his ideas today.
But this help came too late for the men under the East River. In his speech, Hewitt asked people to remember the workers with no names. They were brave, and they built the bridge deep down in the caissons.