[jackson] 



MAGNETIC OBSERVATIONS 



similar magnet at a distance of 28 cms. was 58 degrees. At Agincourt 

 the time of a single oscillation of the same magnet is only 3 . 75 seconds 

 and the deflection at a distance of 20 cms. is only 26.6 degrees. The 

 accm-acy of observations of horizontal force by the method of oscilla- 

 tions and deflections is therefore very greatly dim'nished where the 



