C O N T E N T S 



Introduction .... 

 Abstract of record of the magnetic tour of 1840 

 Abstract of record of the magnetic tour of 1841 

 Abstract of record of the magnetic tour of 1843 

 Deduction of the magnetic declinations 

 Distribution of the magnetic declinations 

 Reduction of the magnetic dip and intensity 

 Distribution of the magnetic dip 

 Distribution of the magnetic intensity . 



v 

 1 

 8 

 17 

 25 

 45 

 4^ 

 64 



n 



( iii ) 



