Report on the Observatory Department. 



435 



APPENDIX I. 



Magnetical Observations, 1900. 



Made at the Kew Observatory, Old Deer Park, Rich- 

 mond, Lat. 51° 28' 6" N. and Long. h l m 15 s *l W. 







The results given in the following tables are deduced from the 

 magnetograph curves which have been standardised by observations 

 of deflection and vibration. These were made with the Collimator 

 Magnet K.C. I. and the Declinometer Magnet marked K.O. 90 in the 

 9-inch Unifilar Magnetometer by Jones. 



The Inclination was observed with the Inclinometer by Barrow, 

 No. 33, and needles 3J inches in length. 



The Declination and Force values given in Tables I to VIII are 

 prepared in accordance with the suggestions made in the fifth report 

 of the Committee of the British Association on comparing and 

 reducing Magnetic Observations. 



The following is a list of the days during the year 1900 which 

 were selected by the Astronomer Royal, as suitable for the deter- 

 mination of the magnetic diurnal inequalities, and which have been 

 employed in the preparation of the magnetic tables : — 



January 3, 8, 9, 30, 31. 



February 3, 6, 7, 13, 28. 



March 5, 11, 21, 27, 28. 



April 3, 8, 15, 22, 25. 



May 9, 10, 14, 21, 28. 



June 10, 11, 16, 20, 25. 



July. 14, 15, 18, 22, 30. 



August 6, 9, 10, 23, 30. 



September 2, 7, 21, 25, 26. 



October 2, 7, 13, 19, 31. 



November 5, 6, 11, 16, 30. 



December 3, 6, 15, 23, 24. 



