28 



MAGNETIC SURVEY OF PENNSYLVANIA. 



No. 3. Homewood, near Pittsburg.-Lat. 40° 28'; long. 79° 59'.5. Aug. 10, 1840. 



Abstract of Declination Observations. 



Set I. 



Set II. 



Magnetic meridian reads, 284 53.2 

 Giving double weight to set I. 



Magnetic meridian reads, 284° 52'. 2. 



Abstract of Observations for Azimuth of Polaris. 



284 50.3 



Mean of times 

 Mean circle reading . 



Aug. 10, chron. fast. 



Chron. time of observation 



Mean 



Corresponding sid. time 



R. A. of Polaris 



Hour angle . 



Azimuth of Polaris . 



Reading of Polaris . 



" astron. meridian 

 " magnetic meridian 



Magnetic declination W. 



6 b 32 m 25". 8 

 286° 16' 32" 



5 h 21 m 22 s . 4 



6 32 25.8 



13 11 03.4 



22 30 13.0 



1 02 30.2 



21 27 42.8 



1° 16'.3 

 286 16.5 

 285 00.2 

 284 52.2 



08.0 



No. 4. Johnson's Tavern, near Brownsville.— Aug. 17, 1840. Lat. 39° 59'.5; 



long. 79° 47'8. 

 Abstract of Declination Observations. 



N. end. 



0-2 W. 

 1.5 E. 

 5.0 W. 

 46.0 W. 



+ 12.4 



S. end. 



2 12.5 E. 



2 6.0 E. 



2 43.3 E. 



2 17.5 E. 



-f2 19.8 



+ 1 16.1 



Azimuth circle reads, 



= +0 18'. 5 

 138 41.8 



Magnetic meridian reads, 139 00.3 



