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X. Contributions to Terrestrial Magnetism. — No. V. 
By Lieut. -Colonel Edward Sabine, R.A., F.R.S. 
Received June 14, — Read June 15, 1843. 
§ 8. Observations within the Antarctic Circle, made on Board Her Majesty's Ships 
Erebus and Terror, in the Summer of 1840 , 1841 , in the Expedition under the 
command of Captain James Clark Ross, R.N. 
§ 9. Observations between Kerguelen Island and Van Diemen Island, made on Board 
Her Majesty's Ship Erebus, July and August 1840 . 
§ 8 . Observations within the Antarctic Circle in the Summer of 1840 , 1841 . 
In the present number of these Contributions, I have the pleasure of laying 1 before 
the Royal Society the magnetic observations made by Captain James Clark Ross, 
and the Expedition under his command, in the first of the three voyages in which 
these researches have been prosecuted within the Antarctic Circle ; and I gladly avail 
myself of the opportunity which the occasion affords, of congratulating the Society 
on the successful completion of the labours and on the approaching return, of an 
Expedition, in which the Fellows individually, and as a body, have taken so strong 
an interest. A large portion of the observations contained in this number were made 
in southern latitudes never before reached by man ; and nearly the whole in a part 
of the globe extremely difficult of access, but containing within itself a field for 
researches peculiarly needed for completing and perfecting, in the words of Halley, 
“ the abstruse theory of terrestrial magnetism.” 
In presenting to the Royal Society this portion of the results of an arduous enter- 
prise, undertaken at their recommendation, it appears no improper departure from 
the usual tone of these communications, to allude very briefly to the causes which, 
under Providence, have conduced to its safe and successful issue ; — to the admirable 
preparation and equipment of the vessels on the part of the Government, — to the high 
qualities of its Commander, manifested in conducting to its close, almost without an 
accident, and to the fullest accomplishment of its objects, a service of such duration 
and peculiar hazard, — and to the excellent spirit in which the Commander has been 
seconded by Captain Crozier, and supported by the officers and seamen who have 
been their worthy associates. 
Viewed merely as an expedition of discovery, its voyages must ever rank high in 
the annals of those maritime achievements of which our country is proud ; but as a 
scientific expedition, which is its more proper character, as well as that in which the 
