436 The National Physical Laboratory. 



Table I. — Hourly Means of the Declination, as determined from the 



Hours 



Preceding 



Mid. 



1. 



2. 



3. 



4. 



5. 



6. 



7. 



8. 



9. 



1 



10. 



11. 





noon. 

















(16° +) West 







Winter. 













1900. 





























Months. 







' 











' 













Jan. . . 



56-7 



54-1 



54-1 



54-4 



54-5 



54 -4 



54-3 



54*2 



54-0 



53-6 



53 -8 



54-4 



55'7 



Feb. .. 



57-1 



54-0 



54-3 



54-6 



54 -5 



54 5 



54-3 



54-0 



53 -9 



54-0 



54-1 



54 -6 



55 '5 



March . 



57 "5 



53-3 



53 -4 



53-4 



53 -1 



52-9 



52-8 



52-5 



51 -8 



50-9 



50-8 



52-0 



54-3 





55-0 



51-0 



51-2 



51-3 



51 '2 



51 -1 



51 -0 



50 -9 



K.n -9 

 ou & 



o 



as •« 



'io o 







Nov. . . 



54 -2 



50'6 



50-9 



51 -1 



51 -1 



51 -1 



51 -0 



50-7 



50 -4 



49 -9 



49 -9 



51-3 



52-8 



Dec. . . 



52-1 



50-0 



50-3 



50 -3 



50-3 



50.4 



50-3 



50-3 



50 '0 



49 -8 



49 '8 



50 -5 



CI .A 



51 4 



lVLeans 



55 -4 



52-2 



52-4 



52-5 



52-5 



52 '4 



52 3 



52-1 



Ol / 



SI -2 



OX 2 



Oi. u 



OA JL 



OO 1 













Summer. 

































- 









/ 





April . . 



57'0 



53-0 



53 -0 



52-8 



52 -8 



52 -4 



52'2 



51 -6 



50-6 



49 -8 



49 9 



51-5 



54-5 



May .. 



57-1 



52-4 



52-5 



52 -2 



51-9 



51 -6 



50-5 



49 *4 



49-0 



49 -4 



50 -1 



52 -3 



54 '8 



June . . 



56-1 



52 -4 



52-3 



52*1 



52 -0 



51 -6 



50-8 



49-9 



49 -4 



49 5! 50-2 



52 -1 



54 -9 



July . . 



57-0 



52-2 



52 3 



52-1 



51-8 



51 -2 



49 '8 



49-4| 49-3 



49-4 



50 -0 



51-0 



53 -4 



Aug. . . 



57 -0 



51 -6 



51-6 



51 -4 



51 '3 



50-8 



50-3 



49-4 



48-6 



48-8 



50-2 



52-6 



55 -3 



Sept, . . 



57 -2 



51 -4 



51-3 



51 -2 



51-0 



50-7 



50'6 



50-0 



49 -1 



48-8 



49-7 



52-2 



54-8 



Means 



56-9 



52 -2 



52-2 



52-0 



51-8 



51 -4 



50*7 50-0 



49-3 



49-3 50-0 



52-0 



54-6 



Table II. — Diurnal Inequality of the 



Hours 



Mid. 



1. 



2. 



3. 



4. 



5. 



6. 



7. 



8. 



9. 



10. 



11. 













Summer Means. 















/ 



-0-5 



-0-5 



-0-7 



-0'9 



-1-3 



-2-0 



/ 



-2-7 



-3 -4 



i 



-3-4 



-2-7 



-0-7 



4-1-9 













Winter Means. 















-0-6 



-0-4 



-0-3 



-0-3 



-0-4 



-0-5 



-0-7 



-1-1 



-1-5 



-1-6 



-0-6 



+ 0-9 













Annual Means. 













1 . 

 1-0-6 



-0-5 



-0-5 



-0-6 



-0-8 



-1 -2 



-1-7 



/ 



-2-2 



-2-4 



t 



-21 



-0-7 



+ 1-4 



Note. — When the sign is + the magnet 



