Mr. Scoresby, jun. on the variation of the magnetic needle, gj 
I conducted on the coast of Spitzbergen, in the years 1815 
and 1817, it will be unnecessary here to enter into the detail 
of these observations or enlarge upon the probable cause of 
the anomalies observed ; it may be sufficient to give a table 
of the most accurate of my observations, and annex to it the 
few general inferences which were drawn from it, during the 
voyagein which most of the observations were made, together 
with such remarks on each inference as seemed to me calculated 
for its elucidation. I shall, however, just premise, that I am 
not unconscious of the great liability to error in observations 
of this kind, and of the variety of causes (arising out of the 
unequal distribution of iron in different ships, whereby nu- 
merous local attractions are formed) which contribute to the 
multiplication of those errors : it is, therefore, with the greatest 
deference that I submit these deductions, particularly as I 
conceive it will require observations to be made under a vast 
variety of circumstances, and in many different vessels, be- 
fore correct and satisfactory conclusions can be drawn. It is 
only then as a step towards facilitating such general conclu- 
sions, the importance of which to our maritime concerns is so 
obvious, that I presume to offer these observations and re- 
marks. 
MDCCCXIX. 
O 
