MAGNETIC OBSERVATIONS. 



89 



Observation for declination. August 4 P. M. 

 Between lO*" 35"" and 11'' 25" by chronometer, the collimator magnet read 

 10° 37' 00" and 37' 40", and the azimuth mark 273° 42' 20" and 43' 40". We have— 



180O + collimator, 190° 37'. 3 



Mark A, 213 43.0 



276 

 23 



54.3 

 22.0 



Azimuth of marlc W. of N. 



Magnetic declination W. 106 27.7 at 6^ P. M. or + 106° 25' when corrected for diur'l var'n. 



Combining this result with the first obtained by S. J. M'Cormick, and giving 

 the Aveight 2 to Radcliif 's determination, and the weight 1 to M'Cormick's, we 

 find the resulting declination -|- 106° 49'. 



Upernavik, North Greenland. August 16 P. M., 1861. 



Observations with portable declinometer and theodolite. II. G. Radcliff, observer. 



Observations for azimuth of marls A. 









Bearings 



of the sun. 









Mark or 



Pocket 



Circle. 





Mark or 



Pocket 



Circle. 





Limb. 



chronometer. 





Limb. 



chronometer. 





A 





266° 45'. 5 



47' 



10 



lO" 42'" 05*^ 



1450 15' 



14' 



A 





266 45 



46 



A 





266 47 



46 



01 



IQh 27m 42= 



148 06 



05.5 



01 



10 31 02 



147 18 



18 



lO 



10 29 55 



148 05.5 



05.5 



10 



10 33 20 



147 18 



18 



A 





266 47 



46 



A 





266 45 



46 



Ol 



10 39 51 



145 15.5 



14.5 











The astronomical paper furnishes AT = — 3'' 41" 52' (sutficiently near for Aug. 

 16). We have the observed times of the sun's centre 10'' 28"" 48% 10'' 32"' IP, and 

 10" 40"" 58% the corresponding computed hour angles 6" 43"° 01', 6'' 46"° 24', and 

 6" 55"" 11% also the computed azimuths of the sun 75° 44'. 8, 74° 57'.0, and 72° 53'. 

 (W. of N.); the corresponding circle readings are 148° 05'. 6, 147° 18'. 0, and 

 145° 14'. 8; the mean reading of the mark A, 266° 46'. 2 and its azimuth 



14° 25'. 4 ^ 



14 25.2 [■ Mean 14° 25'.0 E. of S. 



14 24.4 ) 



Observations for declination. August 17, A. M., 1861. 

 Between 2'' 0"° and 3'' 0"" by chronometer, the collimator magnet read 161° 13' 30" 

 and 14' 00", and the azimuth mark A 219° 21' 30" and 22' 00" ; we find 

 180 + collimator, 341° 13'.7 



Mark A, 219 21.7 



121 



52.0 

 25.0 



Azimuth of mark W. of N. 194 



Magnetic declination W. 72 33.0 at 10'' 50*" A. M., correction for diurnal variation — 21'. 



A result which appears to me rather doubtful, though not differing more than 

 2|° from Captain Inglefield's determination in 1854, which was 75° W. The 



12 June, 1865. 



