u 



RECORD AND RESULTS OP 



Chronometer comparisons : March 8, 1861. Correction of pocket chronometer — 4™ 13'. 9 

 Pocket chronometer. Mean time. Chronometers. Correction on mean time. 



3" 38" sr 



3 39 11 

 3 39 35 



Rate, ST = 



99 



3" 34-" 23M 

 3 34 51.1 

 3 35 21.1 



for 200Y ; 



200'7 : 



8" 22°» 



20= 



1062: 



8 24 



25 



140 : 



8 25 



45 



_4h 4>jm 5gs_9 

 —4 49 21.9 

 —4 50 23.9 



+ P. 04 



1062: —0.01 



740: —0.62 



Pocket chronometer, — 2.50 



Chronometer comparisons, January 31, 1861. 





aTNov. 29. 



ST 



ATJan'y 



31. 



Pocket chr. 

 Jan'y 31. 



Chron's Jan'y 31. 



Mean time. 



aT 

 Pock. 



chr. 



2001: 



— 4'" 



49" 40M 



+ P.04 



—4" 48-" 



35' 



Qh 24" 40' 



2001 : 5^ 10" 21' 



+ 21" 52' 



2" 



48' 



1062: 



—4 



49 21.4 



—0.01 



—4 49 



26 



25 35 



1062: 5 12 21 



+ 23 01 



—2 



34 



140: 



—4 



49 23.1 



—0.62 



—4 50 



02 



26 32 



140: 5 13 41 



+ 23 45 



2 



41 



P. chr 



. 



06.3 1—2.50 













2 



44 







Mean 



—2 



lt3 







A r January 31, 1861 







— 2-" 43= 









Satellite I, disappearance 







. 12 21 46 









Local mean time of eclipse 







. 12 25 03 









Greenwich mean time 

 Longitude Port Foulke . 







. 11 11 41 



est of Greenwich. 







4 52 38 w 





The local time for tlie two eclipses in February is obtained by means of chrono- 

 meter comparisons on the 7th, and the rates of the chronometers and their correc- 

 tions are previously determined. 



< Chronometers. 

 2001: 1" 21" 36' 

 1062: 1 30 53 

 140: 1 33 39 

 Pocket chr. 



Chronometer comparison February 1th, 1861. 



A r March 8. 

 —4" 41" 56'. 9 

 —4 49 21.9 

 —4 50 23.9 

 — 04 13.9 



ATFeb'y 7. 

 — 4" 48" 21' 

 —4 49 26 

 —4 50 05 



Pocket ch'r. 

 2h 42" 15' 

 2 44 19.5 

 2 46 40 



Mean 



Mean time. 

 2" 39" 09' 

 2 41 21 

 2 43 34 



Satellite I, disappearance .... 

 Local mean time of eclipse .... 

 Greenwich mean time 



Longitude Port Foulke 



Correction aT of pocket chronometer, February 8 

 Satellite I, disappearance .... 

 Local mean time of eclipse .... 

 Greenwich mean time . . . . . 



Lonffitude Port Foulke ..... 



A r Pocket chr. 

 —3" 06' 

 —2 53 

 —3 06 

 —3 01 



—3 01 



2 21 42 



14 18 41 



19 11 24 



4 52 43 



—3 04 



8 51 23 



8 48 19 



13 39 52 



4 51 33 



Recapitulation op F^esults for Longitude of Port Foulke from observed Eclipses op 

 Jupiter's first Satellite. 



1860. November 18 . . . .4" 51" 11' 



1861. January 30 

 1861. February 6 

 1861. February 8 



Mean 



4 52 38 



4 52 43 



4 51 33 



4 52 01 ± 16' west of Greenwich. 



