With the aid of these arms the huge machine can move from place to place like a great spider.
The arms can also be drawn together like pincers, and made to grip objects and carry them up to the surface.
The interior of the bell is lighted by electricity. Outside it carries a large headlight, which enables those in the bell to see around them for a distance of a hundred feet.
Experiments have been made in the Great Lakes with this bell, and its first practical work has been to locate the exact position of the steamer Pewabic, which was wrecked in Lake Michigan thirty-two years ago.
Many attempts have been made to find this steamer because she was laden with a cargo of copper ingots, and had besides a large sum of money on board, the two together amounting to about $140,000.
All attempts had, however, been unsuccessful until the Smith bell was used. The steamer was found lying in one hundred and sixty feet of water.
To prove the truth of the find, portions of the wreck were brought to the surface.
The success in Lake Michigan has determined the owner of the diving-bell to try and raise the North German Lloyd steamer Elbe, which was wrecked off the coast of England in 1895.
The owners of the Elbe have already spent about fifty thousand dollars in efforts to recover their vessel.