150 



APPENDIX. 



longitude of the pole, a result which seems to obtain equally, 

 whether the variation is east or west, and which will, there 

 is little doubt, ultimately furnish one of the best tests we 

 can have for confirming the true theory of terrestrial mag- 

 netic action, if we should ever arrive at it, of which rea- 

 sonable hopes may be entertained, seeing the great ad- 

 vances that have been made, within a few years, to- 

 wards reducing magnetic phenomena to the dominion of 

 analysis, and towards which the observations made in our 

 several northern voyages have mainly contributed. 



In order to show the degree of approximation furnished 

 by the different observations alluded to above, we have 

 given the following table of the several computed results. 



