MAGNETIC OBSERVATIONS. 



35 



Errors of Pocket Chronometer, Fletcher, No. 906. 



Station. 



Date. 





Error 



on Local 



Error on 



Greenwich 









Moan Time. 





Mean Time. 



Portsmouth, Va. 



October 29, 1865 



o h 



4™ 



41*. I fast 



5 h 



O m 



28". 7 slow 



Portsmouth, Va. 









" " " 





4 



40.I " 









29.7 " 

 26.3 " 



St. Thomas 









November 13, " 







40 



43.6 slow 









Isle Royal . 









28, " 



1 



3° 



19.4 " 





O 



30.8 " 



Ceara 









December 14, " 



2 



26 



3 2 -S " 



5 







38.5 " 

 3.0 " 



Pernambuco 









23, " 



2 



36 



34-8 " 



4 



56 



Bahia. 









27> " 



2 



22 



6.8 " 





56 



7-3 " 



Bahia . 









29. " 



2 



22 



3.6 " 





56 



10.5 " 



Rio Janeiro 









January 9, 1866 



2 



3 



38-4 " 





56 



9.1 " 



Rio Janeiro 









" " " 



2 



3 



32.8 " 





5 6 



10.7 " 



Monte Video 









'" 18, " 



1 



I I 



27.0 " 





5 6 



22.8 " 



Monte Video 









" 24, " 



1 



I I 



26.5 " 





56 



19.4 " 



Sandy Point 









February 7, " 







12 



48.1 " 





5<5 



2 3-4 " 



Valparaiso . 









March 2, " 







9 



46.4 " 





56 



17.4 " 



Valparaiso 











29, " 





9 



26.8 " 





56 



12.5 " 



Valparaiso 











April 7, " 





9 



23-3 " 





56 



9.0 " 



Valparaiso 











" " " 







9 



23.9 " 



4 



56 



9.6 " 



Valparaiso 











14, " 







1 1 



1.7 " 



4 



57 ' 



47-4 " 



Callao 











26, " 







11 



13.5 fast 





57 



55-6 " 



Payta . 











May 7, " 







26 



41.9 " 





57 



40.1 " 



Panama 











" 14, " 







20 



16.9 " 



4 



57 



44.9 " 



Acapulco 











3°. " 



1 



4i 



22.2 " 



4 



58 



7.2 " 



Magdalena Bay . 









June 8, " 



2 



3° 



4.4 " 





58 



19.6 " 



San Diego . 









15. " 



2 



5° 



3 2 -5 " 



4 



58 



20.1 " 



This chronometer (Fletcher, 906) was habitually carried in my pocket. It was 

 accidentally allowed to run down on the night of December 17th and 18th, 1865, 

 and after remaining stopped twelve hours was wound and compared. Some time 

 between 5 h P.M. of April 13th and 3 h P.M. of April 14th, 1866, it stopped for 

 about l m 37 s , but started again of itself. On June 20th, 1866, when its face showed 

 6 h 45 m P. M. it stopped without any apparent cause, and, as it would not run again, 

 it became useless. 



In observing at San Francisco the box chronometer T. S. and J. D. Negus, No. 

 1287 was used. The observations on June 26th, 1866, showed it to be 



and 



8" 13™ 8 3 .2 fast of local mean time; 



0' 3" 45 s .6 fast of Greenwich mean time. 



