Side-lever engine button
Favourite buttons number 1: Side-lever engine on button made for the British and North American Royal Mail company.
This is a superb button with the tiniest details clearly visible, as you can see by comparing the photo with the drawings.
Side-lever engines were installed in the late 1840s and early 1850s in ships designed for the transatlantic service. The Collins liner Atlantic (launched 1849) had engines that were about twenty percent larger than the engines bought by Cunard for America, Europa, Niagara, and Canada. Except for the slightly smaller size, the 670-horsepower Cunard engines were very much like this 800-horsepower Collins engine.
In the 1850s, Edward Knight Collins was the main competitor of Cunard’s North Atlantic service. In 1847, he negotiated an annual subsidy of $385,000 from the United States government, set up the New York and Liverpool United States Mail Steamship Company, and ordered four 2,885-ton, wooden-hulled side-wheel steamships, the world’s largest. The first vessel of this fleet was named Atlantic, and the others were Pacific, Baltic and Arctic. Atlantic and Pacific were launched on the same day, February 1, 1849. The paddle wheels were 36 feet in diameter, with 36 paddles.
Each ship was powered by two side-lever 800-horsepower [600 kW] engines. Each engine had one cylinder 95 inches (nearly eight feet) [241 cm] in diameter, supplied with steam at a pressure of seventeen pounds per square inch [120 kPa] (which then was at the bleeding edge of boiler technology). When the ship was running on both cylinders at full power, about sixteen revolutions per minute, and a little assistance from auxiliary sails, Collins’ steamers could make 12 or 13 knots (23 to 25 km/h) most of the time. Their coal consumption was enormous, one ton for every 265 revolutions of the paddle wheels, or 85 tons in 24 hours; in a round trip one of these ships burned a quantity of coal almost equal to the ship’s tonnage. Put in modern terms, they got about 6 kilometres (4 miles) to the ton.
Atlantic sailed for Liverpool on her maiden voyage on April 27, 1850. She returned to New York in a record ten days sixteen hours. By then, captains, owners and the newspapers could see it coming — a transatlantic trip in under ten days. In 1851, Cunard averaged 11 days 12 hours eastbound, and 12 days 9 hours westbound; Collins averaged 10 days 21 hours eastbound and 11 days 3 hours westbound. In April 1852, from Liverpool, Pacific reached Sandy Hook in nine days twenty hours fifteen minutes, the first ship, sail or steam, to cross the Atlantic to New York in under ten days.(1)
Sources: The Magnificent Failure, by E. Milburn Carver, (a history of the Collins Steamship Company), originally published in Yankee Magazine (date not known), anthologized in Yankees Under Steam, edited by Austin N. Stevens, published by Yankee, Inc, Dublin, New Hampshire, 1970; and Steam at Sea: Two Centuries of Steam-Powered Ships by Denis Griffiths, Conway Maritime Press, 1997, ISBN 0851776663.