With the onset of the Industrial Revolution in the late eighteenth century, engineers began to harness steam power for many vehicles, including ships. Treadmill- driven paddles had been used since antiquity, and prototype paddle steamers began to appear in the 1780s. But a parallel technology was about to emerge, or perhaps submerge, in the shape of the screw propeller. This acted entirely underwater, as opposed to the paddle which was only partly below the surface—an obvious advantage in a naval battle, with cannonballs flying around. There is still controversy over who can claim credit for the marine propeller. James Watt proposed steam-driven propellers in 1784, but never built them. Many others took out patents on the concept, although none led to a practical device.
The first truly useful screw propeller, and the first to place the screw between the ship's helm and the stern, was developed by Bohemian engineer Josef Ressel-(1793-1857). The first test of the technology took place in Trieste harbor. With forty passengers onboard the steam-driven Civeta, Ressel managed a speed of six knots before the engine exploded. Ressel was banned from further testing. Undeterred, he continued development over the next few decades. But, Ressel lost out to foreign rivals, and there is some suspicion that the invention was sold to Britain where, in 1836, a design was tested by Francis Petit Smith.
The screw was improved by Swedish engineer John Ericsson who in 1839 crossed the Atlantic in forty days using this means of locomotion. The technology went on to power the great steamships of the Victorian era, such as Brunei's Great Eastern.
