Correspondence between the Admiralty and chronometer makers regarding the latter's claims for rewards for making improvements to chronometers. The claims were made principally by J.S. Eiffe and J.G. Ulrich, although there are also claims from R. Molyneux, M.R. Parkinson and C. Frodsham. The correspondents include F. Beaufort, R .Willis, C. Wheatstone, J. Barrow and many of the more famous chronometer and watch-makers. The volume includes unconfirmed minutes of the Royal Society, 10 June 1841; pages extracted from the 'Patent Journal'; a printed paper titled 'Account of improvements in chronometers made by J S Eiffe'; diagrams showing J.S. Eiffe, R. Molyneux and J.G. Ulrich's improvements; and other unlabelled diagrams of the mechanism of chronometers. Part of the volume is in the form of three sets of circulars of inquiry sent to chronometer makers, with their replies. All the claims seem to relate to the standardisation of chronometer rates at all temperatures.