(A)
Some of the bridges, like the George Washington Bridge, and some of the tunnels, such as the Lincoln and Holland Tunnels, are famous. But the most famous of all is the Brooklyn Bridge, which was built over 100 years ago.
Today, engineers have the experience and the special machines to do such things, but at that time, no one knew how to do them. The Brooklyn Bridge was the first bridge of its kind in the world. The box which Washington had studied in Europe was used. It was the size of a house and it was made of wood. It had three sides and a top, but no bottom. Air was forced into the box and water was forced out so the workers could work underwater. No one understood the problems of this kind of work. It was very dangerous and many men were sick. Needless to say (不用说), they were also frightened. Accidents were frequent. Roebling spent a great deal of time with the workers in the box to encourage them.
