A Greek mathematician discovered the basic mathematical relationship of hypocycloidal motion two thousand years ago. In 1666, De La Hare furthered the concept by stipulating that any point on the circumference (rim) of a circle, which rolls inside a circle exactly twice its diameter, moves in a straight line. Murray reversed this by applying steam force to the straight motion, thereby developing rotary motion for power.

Long lost in the history books, Matthew Murray was an outstanding self-taught engineer who invented the short stroke D-valve still in use, the portable steam engine, the tapered bearing, hypocycloidal drive, all metal steam engines, and the self regulating boiler just to name a few. This hypocycloidal engine has all but the last concept in its structure.

James Watt acknowledged that Murray had the finest casting methods in England and his wrought iron work was without equal! Again, this engine represents that, although the paint belies its easy discovery. The engine is very compact, allowing transport by ox cart, and the strength of the A-frame construction revealed itself when the original was found operating without a firm foundation.

Couple all of this with a variable displacement output pump and balanced mechanical loads for a engine from —1806 and one can understand why this engine seemed like a Ferrari next to a Plymouth.