Behind the two rear wheels is a ship propeller.

Bronze is still commonly used in ship propellers and submerged bearings.

Manganese originally made ship propellers.

There they painstakingly assembled more than $17 million worth of computer-controlled machine tools used to make ship propellers.

A block west, along the Delaware River, huge ship propellers and other scrap metal are vestiges of that success.

Josef Ressel (1793 - 1857), inventor of the ship propeller.

He died in 1857 and in 1866 the US academy confirmed his license for a ship propeller.

The revolutionary choice of objects in that show included a ship propeller and self-aligning ball bearing.

He swung a 10-pound hammer much of his life, battering ship propellers into shape.