30 



M A G X E T I C SUB V B V O F P E N'XSYL Y A MA. 



So. 6. Baltimore.— Aug. 27, 1840. Lat. 39° 17'.8; long. 16° 36'. 6. 

 Abstract of Declination Observations. 



N. end. 



47. C E. 



32.0 E. 



1 2:..; E. 

 1 01.2 E. 



_0 56.6 



S. end. 



18.0 E. 



7.6 E. 



2 22.0 E. 



2 20.5 E. 



+ 1 110 



+ 10.2 



Azimuth circle reads, 



=0° 02'.; 5 

 210 511 



Magnetic meridian reads, 210 59.6 



Abstract of Observations for Azimuth of Polaris. 



Mean of times 

 Mean circle reading . 



Aug. 27, chron. fast . 



Chron. time of observation 



Mean 



Corresponding sid. time 



R. A. of Polaris 



Hour angle . 



Azimuth of Polaris . 



Reading of Polaris . 



" astrom. meridian 



" magnetic meridian 



Magnetic declination W. 



12 h 59 m 04". 9 

 215° 12' 44" 



5 h 08 m 

 12 59 

 50 

 15 

 02 

 13 



7 

 18 



1 

 11 



2 8 s . 5 

 04.9 

 36.4 

 52.7 

 40.6 

 12.1 



1° 56'. 6 

 215 12.7 

 213 16.1 

 210 59.6 



2 16.5 



Recapitulation of Results foe Magnetic Declination, 1840. 



Harrisburg .... July 25, 



Huntingdon .... July 30, 



Eome wood, near Pittsburg . . Aug. 10, 



Johnson's Tavern, near Brownsville . Aug. 17, 



5. Irwin's Mill, near Mercersburg . . Aug. 24, 



6. Baltimore .... Aug. 27, 



3° 12'. 5 W. 



52.3 

 08.0 

 25.2 

 54.4 

 16.5 



1. Philadelphia. 



2. Easton. 

 :;. Williamsport. 



4. Curwinsville. 



5. Mercer. 



Declination Stations of 1841. 



6. Erie. 



7. Dunkirk. 



8. Ellicottville. 



9. Bath. 

 10. Silver Lake. 



Chronometer Grant No. 3861, London. 

 For chronometer error and rate. 



July 19, Philadelphia time . 



Aug. 30, " " . 



Sept. 14, " " . 



(Previous to July 19. the chron. was gaining 2 s . per day.) 

 The longitude of the State house, to which the above refers, is 75° 08' 41". 9, or in time 5"00 m 34."8. 



