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Report of Magnetical Observations at Falmouth Observatory 

 for the Year 1896. Latitude 50° 9' 0" N. and Longitude 

 5° M 35" W. ; height, 167 feet above mean sea-level. 



These observations have been made by instruments purchased from 

 the Government Grant Fund administered by the Royal Society. 



Photographic curves of Magnetic Declination and of Horizontal 

 Force variations have been regularly taken throughout the past year, 

 with the exception of three days in December, and the magnets have 

 worked satisfactorily throughout. 



The results obtained from the Vertical Force Magnet are not 

 sufficiently reliable for publication. 



The scale values of the instruments were determined on 1st 

 January, 1897. The following values of the ordinates of the photo- 

 graphic curves were then found : — ■ 



Decimation, 1 cm. = 0° 11'?; 



Bifilar, 1 cm. ^H. = 0*00050 C.G.S. unit. 



The principal magnetic disturbances recorded during the year 

 occurred on the following dates : — January 3, 4, 5, 31 ; February 2, 

 4, 28; March 4, 26, 27, 28; April 22, 23, 24; May 2, 3, 17, 18, 20; 

 June 16 ; July 3, 4, 5 ; August 1,2; September 18; October 11, 12 ; 

 December 3, 4. 



Observations with the Absolute Instruments have been made 

 monthly, of which the following is a summary: — 



Determinations of Horizontal Intensity, 34. 



„ Inclination, 34 sets of four. 



,, absolute Declination, 34. 



Following the method adopted in the five previous years, it is 

 intended that the observations be reduced, and that the Declination 

 and Horizontal Force curves for five quiet days in each month of the 

 year — selected by the Astronomer Royal — be tabulated and prepared 

 for publication, in accordance with the International scheme. The 

 results will be printed in the Royal Cornwall Polytechnic Society's 

 Annual Report, and also in the ' Proceedings ' of the Royal Society. 



The following are the principal results of the magnetic elements 

 for the year 1896 : — 



Mean Westerly Declination, 18° 47''5. 



Mean Inclination, 67° 5'*0. 



Mean Horizontal Force, 0-18554 C.G.S. unit. 



VOL. LXI. 



K 



