CHRONOMETERS. Ill 



prizes, shall cease after the present year, a few remarks on the origin of those trials, and 

 on the favourable effect which they have had on the art of chronometer making", may not 

 inappropriately close our observations. 



Notwithstanding the encouragement which Government had long afforded to the art, 

 by purchasing chronometers largely, and at liberal prices, for the use of the navy ; and 

 the very considerable rewards which had been given to three of the leading artists 

 (3000/. each) for the superior performance of some instruments made by them, yet the 

 general state of the art was much below what was generally believed, and might 

 have been expected. 



Aware of this fact, and desirous that the art which we exercised should participate in 

 the general improvement, we, in 1818, addressed a letter to J. W, Croker, Esq., at that 

 time Secretary to the Admiralty, respectfully suggesting that Government might further 

 and most essentially aid the progress of the art, by giving frequent and small rewards 

 to ingenious workmen who made instruments that actually performed well, without refer- 

 ence to the principles on which they were constructed. 



The public trials at the Royal Observatory commenced in 1820, and the performance 

 of the chronometers on the first trial proved the correctness of the opinion which we had 

 formed as to the general state of the art of chronometer making. The prizes of 300/. 

 and 200/. were that year adjudged to chronometers which Government would not at 

 the present time purchase at any price. 



Several of the chronometers which we sent on trial in the various scientific ex- 

 peditions to the Polar Seas and towards the Equator, having performed satisfactorily, 

 we sent some of our experimental chronometers to Greenwich on trial, a few years after 

 the public trials were first estabhshed ; and the opportunity thus afforded us of having 

 the effect of our successive alterations tested by daily observation, enabled us to detect 

 many minute sources of error, which we should otherwise most probably never have 

 discovered. 



The opportunity, too, of returning for trial chronometers which, having performed 

 unsatisfactorily we had endeavoured to improve, gradually led us to the discovery of 

 the principle which enables us now to control at pleasure, and to counteract, any general 

 tendency in chronometers to deviate from their rates. 



We are. Sir, 



Yours, respectfully, 



PARKINSON & FRODSHAM. 



To Copt, Sir John Ross, li.N., 

 Sfc. 6)C. 4-c. 



