Horse Power Computer for Steam, Gas & Oil Engines
Golding, Henry Albert: Charles Grffin & Co., 1908.
A rotating logarithmic computer [sic, i.e. calculator] consisting of three moving circular varnished card pieces of graduating size turning around a brass rivet on a back-board, 6.5 x 6.5 inches, 16 x 16 cms. Together with the original 12 page instruction manual, illustrated.
The calculator and its accompaying manual are both in fine near-immaculate condition, as issued, with tissue guard in their original white cardboard box, the box itself being a touch bowed.
Henry A. Golding, the designer of this calculator, was the author of "The Theta-Phi diagram practically applied to steam, gas, oil, and air engines" first published in 1898.
In 1906, he submitted a complete specification patent application for "Improvements In Power Computing Slide Rules For Steam and Other Engines" (Original Patent Application Number 8,196). This computer, marked "Golding's Patent", is almost certainly the result of that application.
The calculator was designed primarily for steam engine but enables calculations for two-stroke gas and oil engines.
A Copac search shows only a single instance of this early computing machine recorded as appearing in the holdings of major British and Irish libraries.