xlii REPORT— 1844. 



It was the publication of Colonel Sabine's • Report on the Variations of the 

 Magnetic Intensity at different points of the Earth's Surface,' and the maps 

 whicli accompanied it, which appeared in our volume for 1837, whicli first en- 

 abled the celebrated Gauss to assign provisionally the coefficients of his series 

 for expressing the tnagnetic elements : the proper data of this theory are 

 the values of the magnetic elements at given points uniformly and systema- 

 tically distributed over the surface of the earth, and it was for the purpose 

 of supplying the acknowledged deficiency of these data and of determining the 

 laws which regulated the movements of this most subtle and mysterious ele- 

 ment, which induced the Association to appoint a Committee to apply, in con- 

 junction with the Royal Society, to Her Majesty's Government to make a 

 magnetical survey of the highest accessible latitudes of the Antarctic seas, and 

 to institute fixed magnetical and meteorological observatories at St. Helena, 

 the Cape, Hobarton, and Toronto, in conjunction with a normal establishment 

 at Greenwich, and in connection with a great number of others on the con- 

 tinent of Europe, where systematic and simultaneous observations could be 

 made, which would embrace not only the phaenomena of magnetism, but those 

 of meteorology also. It is not necessary to add that the application was 

 promptly acceded to. The views and labours of the framers of this magnifi- 

 cent scientific operation, the brilliant prospects of discovery which it opened, 

 the noble spirit of cooperation which it evoked in every part of the civilized 

 world, were alluded to in terms so eloquent and so just in the opening ad- 

 dress of Mr. William Vernon Harcourt, when occupying this Chair at Bir- 

 mingham, that I should do little justice to them if I employed any terms but 

 his own, and I must content myself with simply referring to them. Much of 

 what was then anticipated has been accomplished, much is still in progress, 

 and much remains to be done ; but the results which have already been ob- 

 tained have more than justified our most sanguine expectations. 



Sir James Ross has returned without the loss of a man, without a seaman 

 on the sick list, after passing three' summers in the Antarctic seas, and after 

 making a series of geographical discoveries of the most interesting and import- 

 ant nature, and proving in the language of the Address to which I have just 

 referred, " that for a man whose mind embraces the high views of the philoso- 

 pher with the intrepidity of the sailor, no danger, no difficulty, no inconvenience 

 could damp his ardour or arrest his progress, even in those regions where 



" Stern famine guards the solitary coast, 

 And winter barricades the realms of frost." 



The scientific results of the two first years of this remarkable voyage have 

 been discussed and published by Colonel Sabine in his ' Contributions to Ter- 

 restrial Magnetism,' in the Transactions of the Royal Society, and they are 

 neither few nor unimportant. They have shown that observations of the de- 

 clination, dip and intensity, the three magnetic elements, n)ay be made at sea 

 with as much accuracy as on land, and that they present fewer anomalies from 

 local and disturbing causes ; that the eft'ects of the ship's iron are entirely 

 due to induced magnetism, including two species of it, one instantaneous, coin- 

 cident with and superadded to the earth's magnetism, and the other a polarity 

 retained for a shorter or longer period, and transferable therefore during its 

 operation by the ship's motion from one point of space to another ; that in both 

 cases they may be completely eliminated by the observations and formulae 

 which mathematicians have proposed for that purpose. No intensity greater 

 than 2"1 was observed; and the magnetic lines of equal declination, dip 

 and intensity, were found to differ greatly from those laid down in Gauss's 

 theoretical map, the northern and southern hemisplieres possessing much 



