Principles and Explanations of Timekeepers (A British Horological Institute reprint celebrating its 125th anniversary year)

Quarto, list of subscribers (6 pages), Introduction and Technical Appraisal by Jonathan Betts (21 pagea, black and white illustrations in text), facsimiles of "The Principles of Mr Harrison's Timekeepr" (31 pages, plates); "Explanations of the Time-keepers, constructed by Mr Thomas Earnshaw and the late Mr John Arnold" (63 pages, plates, some folding), fine condition in marbled paper covered boards and calf spine, gilt decorated and titled on spine, signed by the President of the Institute on the front free end-paper.