Theory and Practice of Just Intonation: With a View to the Abolition of Temperament : as Illustrated by the Description and Use of the Enharmonic Organ, Presenting the Power of Executing with the Simple Ratios in Twenty Keys, with a Correction for Changes of Temperature, Built by Messrs. Robson ... for the Exhibition of 1851, and an Appendix, Tracing the Identity of Design with the Enharmonic of the Ancients