By D Zimmermann

The editor recently asked for an idea for a challenging model. I suggested that the Stirling traction engine would be something that would test the design abilities of a brave model engineer. Julius de Waal came up with some impressive drawings.

The editor’s next challenge was suggest something that would be interesting to research and challenging to make. So for those who can take on a serious challenge over the next several years, have a good look at the Corliss Centennial Engine.

It has been modelled at least once before. The fine model, shown above, is in the collection of the Chicago Museum of Science and Industry.

What’s more a complete set of blue prints exists at the National Museum of American History. See

And its a splendid opportunity to put into practice the fabrication techniques of Jason Ballamy.

Numerous photos and illustrations were published at the time, and we include some of these below.

The Centennial was the largest engine that the Corliss Steam Engine Company built. It was first located in the Machinery Hall of the Centennial Exposition in Phillidelphia in 1876. It was started up by President Ulysses S. Grant and the Emperor Dom Pedro of Brazil backed by a choir of 1000 singing Handel's Hallelujah Chorus, a 150-piece band playing the Centennial March composed by Richard Wagner, followed by a 100 gun salute. They knew how to celebrate engineering in those days!

The engine frame was shaped like the capital letter A and from the floor to the top of the walking beam was 40’. The engine had a 44” bore and 10’ stroke, was more than 45’ tall, had a 56 ton, 30’ diameter x 24” flywheel, the largest gear wheel in the world. The crankshaft was 18” diameter and 12’ long. The gear wheel meshed with a pinion wheel that powered 3268’ of main power shafting located in tunnels. From the main power shaft, approximately 13,000' of overhead shafting and two miles of belting applied to the machinery in the car shop. The engine was capable of developing 2500 horsepower.

After six months at the Exposition the engine was shipped back to the Corliss Factory in Providence. Seven years later it was sold to the George Pullman company in Chicago and ran their factory until 1910.  when it was scrapped after electricity replaced steam. Portions of the foundation of the original engine house and power shaft tunnels are still visible on the site.