40 



Hourly Observations of Magnetometers, July 24 — 30, 1844. 



Declination. Magnet untouched, May 29<i — Aug. 4*1. 

 BiKiLAR. Observed 2'» after the Declination k = 0-000140. Balance. Observed 3™ after the Declination, k = 0-0000085. 



t Kxtra Observations made. 



July 20-^ 2^ 30". The balance needle vibrated considerably by the accidental approach of a mass of steel, which has affected the tini 

 of vibration, and seems also to have affected the position of the needle. 



