British Steam Engine Recognized As First Boulton and Watt with Parallel Motion

Enlarge Image Image Gallery ASME and the Museum

An 18th century engine, survivor of a 102-year stint in a London brewery and now housed in an Australian museum, has been designated an ASME historic mechanical engineering landmark.

The first Boulton and Watt rotative engine with parallel motion was designated the 19th International Mechanical Engineering Landmark by the American Society of Mechanical Engineers (ASME). During ceremonies on April 17, Dr. L. S. Fletcher, president of the Society, presented a bronze plaque to Dr. Lindsay Sharp, director of the Power House Museum, part of the Sydney Museum of Applied Arts and Sciences, in Australia.

The parallel motion mechanism is the critical element that allowed long-stroke pumping engines to become double-action and thus able to produce rotational motion. Built in 1785 as a single-acting engine, the Boulton and Watt was altered to its present double-acting configuration in 1795.

Museum staff Bill Bannister and Bert Bruin check parts near the 14-foot flywheel of the Boulton and Watt steam engine now in the Museum of Applied Arts and Sciences in Sydney, Australia. Photo courtesy of ASME and the Museum.

Replaced in 1887 by a more compact, higher powered compound steam engine, it was donated to the Museum and shipped to Australia, where it has been on display since 1888. It was once again restored to working condition for its bicentennial last year.

The engine was high technology for its day and more imposing than other mechanical achievements of the time the windmill and the clock. In May of 1797, King George III took Queen Charlotte and their children to inspect the Brewery works, the chief attraction being the engine. Although of modest capacity, it set a good example, and by 1796, 11 other Boulton and Watt engines were at work in London.

With the ever increasing industrial activity of the 18th century, rotational power beyond that derived from animals, water, or wind was desperately needed. New comen atmospheric pumping engines were used for mine drainage and water systems, but the high cost of fuel was limiting. Millwork was dependent upon shaft power, but these engines had inadequate drives. The unlimited industrial application of a rotative engine was recognized by James Watt, an engineer who in 1776 began a partnership with industrialist Matthew Boulton.