2 REPORT— 1842. 



not yet be known ; but it is understood that intensities have been observed by 

 Captain Ross in these regions exceeding 2\ times the minimum observed by him 

 near St. Helena; and that intensities of this high value prevail with little 

 variation over a space extending from the 47th to the 77th degrees of lati- 

 tude The intensity in lat. 76°, where the nearest approach was made to the 

 magnetic pole, was found to be actually less than in 47°. The nearest ap- 

 proach to that interesting point, viz. the magnetic pole, was made in lat 76° 

 12', long. 164° east, the dip being between 88 and 89 degrees. 



It was mentioned in our last Report that the publication of the magnetic 

 observations of the expedition had, at the request of the Admiralty, been 

 placed under the superintendence of Lieut. Col. Sabine. The first portion 

 of this work has been published in the Phil. Trans, of the present year, con- 

 taining the observations of intensity made at sea between England and Ker- 

 guelen Island. In this paper, the 3rd of a series of " Contributions to Ter- 

 restial Magnetism" which we owe to Col. Sabine's zeal and industry, the whole 

 series of interesting observations made on board each of the ships with Fox's 

 statical or deflecting magnetometer, are carefully analysed, projected, and rea- 

 soned on. The results are every way most satisfactory as regards the prac- 

 ticability of observing with precision at sea, in all sorts of weather; as a 

 proof of which, it will be necessary only to mention, that out of 647 observa- 

 tions of this kind made between London and the Cape of Good Hope, on 

 board the Erebus, one only was found so far irreconcileable with their general 

 tenor as to be declared doubtful : while the observations taken on board both 

 ships, when compared, exhibit a steady accordance which cannot be accidental, 

 and may well be termed beautiful. From this examination it would appear (if 

 earlier observations can be relied on) that the line of least intensity on suc- 

 cessive meridians in the middle and eastern part of the Atlantic Ocean is tra- 

 velling rapidly northward. 



In addition to the sea observations, the expedition since our last Report 

 has made absolute determinations and observed terms as follow : — 



1840. Nov Auckland Island. 



1841. May and June Van Diemen Island. 



July Sydney. 



Aug., Sept, Oct., Nov New Zealand. 



The November term having been kept in the Bay of Islands, the expedi- 

 tion, according to the last letter received from Capt. Ross, dated Nov. 22, 1 841 , 

 was to sail thence the day following to resume the exploration of the Antarctic 

 regions. His intention, as stated in that letter, Avas to traverse the isodynamic 

 oval surrounding the focus of greatest intensity, supposed to be in lat. 60°, 

 long. 235° east, and steering thence directly south to the edge of the ice-pack, 

 to make, on reaching it, for the point at which the first year's exploration of 

 the coast of the new continent terminated, with intention to pursue the barrier, 

 wherever its course may lead. The working out of this arduous undertaking 

 may of course involve a winter spent within the antarctic circle. Should it 

 be otherwise, we may expect shortly to hear of the arrival of the expedition 

 at the Cape of Good Hope, or at the Falkland Islands *. 



2. British and Foreign Observatories. — Extension of the period for which the 

 British Establishments have been granted by the British Government. 



All the British and Indian magnetic observatories, that at Aden excepted, as 



* By letters received since the meeting of the British Association at Manchester, we laern 

 that the Expedition arrived at the Falkland Islands in April of the present year, and was to 

 sail again for the Antarctic Circle in October. 



