[ 130 ] 
EXPERIMENTS ON THE DIPPING NEEDLE, 
Stromnefs in the illes of Orkney, lat. 58'' 59' North, 
long. 3° 30' Weft from London, June 9, 1774. 
The index placed Eaft. 
The index placed Weft. 
The poles of the needle changed, the index 
placed Weft. 
The index facing the Eaft. 
In thefe obfervations the needle was placed horizon- 
tal, and the vibration continued between nine and ten 
minutes. The inftrument was fet in the middle of a 
room up one pair of ftairs ; but being apprehenfive that 
the iron-gratfe, fender, poker, and tongs, might, in fome 
meafure, afFe6t the needle, I determined to make a trial 
in the open air, and in a place free from fuch obftacles. 
75 50 
76 o 
75 45 ■ 
75 45 
75 40 . 
74 55 ' 
75 o , 
75 20 
75 25 . 
75 25 
7610 . 
76 15 . 
76 25 i 
77 o J 
E X r E“ 
