Narrative of the surveying voyages of his majesty's ships Adventure and Beagle (vol.2- Appendix): between the years 1826 and 1836 : describing their examination of the southern shores of South America, and the Beagles's circumnavigation of the globe

344 APPENDIX. Observatory at the II. N. College at Portsmouth to Greenwich. Eleven ChronometL-rs. Eight Days. H. M. L o 04 H. M. S. H. M. S. A 04 22,35 04 22,35 B 24.57 ,, 24,57 C 22,63 .. 22,63 D 26,73 ,. .... 26,-3 G 26,46 .. 26,46 n 29,79 •N O s z s. H. M. S. 24,07 04 24,07 26,63 .. .... 26,63 29,17 .. .... 29,17 23,29 .. .... 23,29 21,81 ;; I 21,81 •• 25,23 24,77 Mean Preferred Oh. 04m. 24.,8s. H. M. S. Angra to Devonport 1 32 09,7 Angra to Falmouth 1 28 39,5 Falmouth to Devonport 03 30,2 Devonport to Grtenwich 16 40,3 Falmouth to Greenwicli 20 10,5 Devonport to Greenwicli 16 40,3 Portsmouth to Greenwich 04 24,8 Devonport to Portsmouth 12 15,5 fO 04 24,8 <^0 12 Again ... ... ^ 15,5 to 03 30,2 Greenwich to Falmouth 20 10 5 While looking over the preceding results, enquiry may be made for those of the other chronometers : I should, therefore, mention that the others were useless. Some of the watches stopped ; others altered their rates suddenly ; and in one case (R) a mainspring broke when the chronometer had been going admirably, till that moment. Four chronometers were left with Mr. Usbome, on the coast of Peru, and in consequence of these diminutions of our original num- ber, there were but eleven watches in tolerably effective condition during the last two principal links of the chain, namely, from Port Praya to the Azores, and from the Azores to Devonport. Five years is a long time for chronometers to preserve their capa- bility of going steadily, under various changes of climate, without being examined, and perhaps cleaned or fresh oiled, by an expe- rienced chronometer maker.