Comparisons of Magnetic Standards, 190.'i-14 



227 



Table 7 A. Results of Declinalion Comparisons at Ihc ClwUcnham Obsermtory, 190S-1913. 



Series 



Date 



Local mean timCi Declination obtained 



1908 

 Feb. 5 

 5 

 6 

 6 

 6 

 7 

 7 

 7 

 7 

 7 

 7 



From 



h m 



13 32 

 15 33 



8 08 



10 16 



11 40 

 11 13 



14 19 



14 34 



15 56 



16 06 

 16 16 



S 34 

 10 28 



To 



C. I. W. 



41 



42 

 14 

 22 

 47 

 20 

 20 

 40 

 03 

 13 

 22 

 40 

 34 



31.2 

 35.4 

 25.6 

 26.0 

 27.7 

 26.5 

 32.2 

 33.3 

 30.7 

 31.3 



31.6 

 25.1 

 25.0 



Cheltenham 



31.9 



36.0 



25.5 



26 



28 



26 



32 



33 



31 



31 



32 



25 



24 



C.I. W.- 

 Cheltenham 



+0.7 

 +0.6 

 -0.1 

 +0.4 

 + 0.5 

 -0.5 

 + 0.1 

 -0.2 

 +0.9 

 +0.6 

 + 0.0 

 + 0.1 

 -0.1 



Mean value of (C. I. W.- Cheltenham) ! +0.28 



II 



29.6 

 32.8 

 32.8 

 25.7 

 27.3 

 34.6 

 32.9 

 27.2 



29.4 

 32.7 

 32.5 

 25.8 

 26.9 

 34.7 

 33.1 

 27.2 



Mean value of (C. I. W. Cheltenham) 



-0.2 

 -0.1 



-0,3 

 + 0.1 

 -0 4 

 +0.1 

 +0.2 

 0.0 



-0.08 



III 



1910 

 Apr. 



46.1 

 44.8 

 44.5 

 41.5 

 36.7 

 37 4 

 .58.0 

 43.4 

 44.8 

 44.5 

 44.1 

 40.7 



-5 



46.2 

 45.0 

 44 4 

 41.9 

 37.0 

 37.4 

 38.2 

 43.8 

 44.5 

 44.9 

 44.2 

 40.9 



Mean value of (C. I. W. Cheltenham) . 



IV 



+ 0.1 

 +0.2 

 -0,1 

 + 0.4 

 +0.3 

 0.0 

 + 0.2 

 + 0.4 

 -0.3 

 + 0.4 

 +0.1 

 +0.2 



+0.16 



Mean value of (C. I. W. Cheltenham) . 



Remarks 



C I. W. magnetometer 

 No. 5 used ; observer, 

 J. ( '. Pearson. 



(weifcht, 1.0) 



'. I. W. magnetometer 

 No. 7 used; oljserver, 

 H. W. Fisk. 



(weight, 1,0) 



C. I. W. magnetometer 

 No. 5 used ; observer, 

 J. C. Pearson. 



(weight, 1.0) 



C. I. W. magnetometer 



No.3(standard)used; 

 observer, H. M. W. 

 Edmonds. 



+0.32 (weight, 1.5) 



Hence we get from the four series the weighted mean value: C. I. W. 

 +0'. 19 for 1908-1913). 



Cheltenham = 



