Piston rods and parallel motion blocks. The SS 'Great Britain' was the first screw-propelled vessel to cross the Atlantic, as well as being the first iron-built ship to do so. She sailed from Liverpool to New York in 1845, taking 14 days 21 hours to make the crossing. She was completed in Bristol in 1843 for the Great Western Steamship Company to the plans of Isambard Kingdom Brunel (1806-1859). Accommodation was provided for about 360 passengers. The Great Britain was employed in the Australian trade from 1852, and was converted into a sailing vessel in 1882. Engraving from 'Great Britain, Atlantic steam ship of 3500 tons: constructed of iron, with engines of 1000 to 2000 horse-power, and a screw propeller', published in London in 1847.
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