DIP, &c. OF THE MAGNETIC NEEDLE. 



I HAVE already mentioned that I was in possession of three dipping needles: one the 

 construction of Mr. T. Jones, one by Mr. Pope, and the last by myself on the plan of 

 Mr. Jennings. The two lastmentioned served to prove the accuracy of the first, which 

 was used by me in the month of May, 1830, where I found the dip, by all three dipping 

 needles, to be eighty-nine degrees and fifty-five minutes ; and subsequently, at Padliak 

 or Spence bay, where it was found to be eighty-nine degrees and fifty-six minutes, by 

 six sets of observations taken on the two days which I remained there for the purpose ; 

 but the variation of the compass was found to he considerably less, being only sixty- 

 eight degrees and thirty-five minutes west, making a difference of twenty degrees and 

 twenty-five minutes, sufficient to indicate nearly where the Pole must be found. It 

 is, however, but justice to say, that the position assigned to the Magnetic Pole by 

 Commander Ross, was made entirely from his own observations, and if any discre- 

 pancies are found, I conceive that they must have proceeded from damage which 

 the needle sustained while in my possession at Padliak ; but which, if I may judge 

 from the subsequent observations, was not so great as I at first apprehended. 



I had also several observations on the magnetic force during the first year; but these 

 1 did not follow up, because it was evident that every winter, the magnetic force of 

 the needle constructed for that purpose, had diminished probably from the severity of 

 the climate : these needles are still in my possession. 



The observations which I made on Sound, have so nearly the same result as those 

 made on the preceding voyages, that they need not be detailed here ; as also those on 

 the Radiation of Solar Heat, the maximum of which was eighty-four degrees of Fahren- 

 heit, in an ivory-mounted thermometer, suspended between two poles. While opposite 

 to black-painted canvas it rose to ninety degrees. 



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