Beschreibung:

Harrison, John THE PRINCIPLES OF MR. HARRISON'S TIME-KEEPER, WITH PLATES OF THE SAME. PUBLISHED BY ORDER OF THE COMMISSIONERS OF LONGITUDE. LONDON: W. RICHARDSON AND S. CLARK, 1767 FIRST EDITION, 4to (260 x 199mm.), 31pp., half-title, 10 folding engraved plates, contemporary red morocco, fully gilt, blue morocco labels, gilt edges A magnificent copy. Harrison's chronometer revolutionised the science of navigation, and solved one of the greatest scientific problems by providing navigators with the means to determine an accurate geographical location at any moment while at sea. In 1714 Parliament had passed an Act offering up to £20,000 to anyone who could solve the problem. Yorkshire clockmaker John Harrison (1693-1776) began work in the 1730s on a chronometer which was tested on two voyages to the West Indies in 1761, and 1764. Harrison had a prolonged and difficult struggle to convince the Board of Longitude that the requirements of the Act had been met, due to prevailing scientific prejudice against mechanical devices and it was not until 1773, following a final demonstration in the King's private observatory at Kew, that the 80-year old inventor was at last awarded his full financial reward. The invention made possible a new age in exploration and the charting of the seas. "There has possibly been no advance of comparable importance in aids to navigation until the introduction of radar" (PMM 208).