balance beam

A connecting rod worked a balance-beam, which worked the air-pump, feed-pump, and plug-rod for moving the valves.

A large balance-beam was attached to the pump-rods, near the bottom cross-head.

Mr. Jump, a director on the mine, pointed out a balance-beam that Mr. Trevithick had put up thirty years before.

The scales consisted of two tin pans of equal size and weight hung from a balance beam.

It was evidently a very slim canoe with a balance beam and sails.