156 APPENDIX. 



three points westerly at Sea-horse Point, all westerly devia- 

 tions would appear to be three points more than they actu- 

 ally were, and all easterly deviations three points less ; hut 

 when in the more northern parts of the voyage, as the needle's 

 direction then nearly agreed with the true meridian, the 

 errors on both sides would be nearly equal to each other, 

 and consequently the easterly ea'rors would appear to in- 

 crease, and the westerly to diminish, as was found to be the 

 case. 



Having thus taken a general vieAV of the phenomena, 

 which we ought d priori to have expected the needle to jjre- 

 sent, let us take the several remarks as noted in the Journal, 

 and see how far they m.ay he individually explained upon 

 the principle ahove established. 



(a) Qj) (c) These remarks have been sufficiently illus- 

 trated, by showing the great reduction of the directive in- 

 tensity. 



(c/) This remark was made by Captain Franklin, but it is 

 obviously the necessary consequence of a change of position 

 in an east and west line so near to the magnetic pole. 



(e) It has been already shewn that, with the ship's head 

 to the southward, the magnetism of the earth and ship were 

 opposed to each other, and having been also nearly equal, 

 the compass would necessarily be inactive. With the ship's 

 head north, the needle was under the compound influence of 

 the ship and earth, and was therefore more active, although 

 not more useful. Gilbert's compass having been freed from 

 the magnetic action of the vessel, and that of the earth 

 having been insufficient to give it direction, it would neces- 

 sarily stand in any position. 



(/■) This sudden change in the larboard compass was most 

 likely the effect of accident ; with so little directive force, 

 the needle is of course easily displaced. The error with the 



