186 COSMOS. 



epochs, observations are made at intervals of 2-J- minutes, and 

 continued for 24 hours consecutively. A great English astro- 

 nomer and physicist has calculated* 4 that the mass of observa- 

 tions \yhich are in progress will accumulate in the course of 

 three years to 1,958,000. Never before has so noble and 

 cheerful a spirit presided over the inquiry into the quantita- 

 tive relations of the laws of the phenomena of nature. We 

 are, therefore, justified in hoping, that these laws, when com- 

 pared with those which govern the atmosphere and the remoter 

 regions of space, may by degrees lead us to a more intimate 



Germany and Sweden, and the whole of Italy. (Resultate der Beob. des 

 magnetisclien Vereins im Jahr, 1838, s. 135, and Poggend. Annalcn, 

 bd. xxxiii., s. 426.) In the magnetic association that was now formed 

 with Gottingen for its centre, simultaneous observations have been 

 undertaken four times a year since 1836, and continued uninterruptedly 

 for 24- hours. The periods, however, do not coincide with those of the 

 equinoxes and solstices, which I had proposed and followed out in 1830. 

 Up to this period, Great Britain, in possession of the most extensive 

 commerce and the largest navy in the world, had taken no part in the 

 movement which since 1828 had begun to yield important results for 

 the more fixed groundwork of terrestrial magnetism. I had the good 

 fortune, by a public appeal from Berlin, which I sent, in April 1836, to 

 the Duke of Sussex, at that time President of the Eoyal Society, (Lettre 

 de M. de Humboldt & S.A.R. le Due de Sussex, sur les moyens propres 

 a perfectionner la connaissance du magn6tisme terrestre par 1'gtablisse- 

 ment des stations magnetiques et d'Observations correspondantes), to 

 excite a friendly interest in the undertaking which it had so long been 

 the chief object of my wish to carry out. In my letter to the Duke of 

 Sussex I urged the establishment of permanent stations in Canada, 

 St. Helena, the Cape of Good Hope, the Isle of France, Ceylon, and 

 New Holland, which five years previously I had advanced as good 

 positions. The Royal Society appointed a joint physical and meteorolo- 

 gical committee, which not only proposed to the Government the esta- 

 blishment of fixed magnetic observatories in both hemispheres, but also 

 the equipment of a naval expedition for magnetic observations in the 

 antarctic seas. It is needless to proclaim the obligations of science in 

 this matter to the great activity of Sir John Herschel, Sabine, Airy, 

 and Lloyd, as well as the powerful support that was afforded by the 

 British Association for the Advancement of Science, at their meeting 

 held at Newcastle in 1838. In June 1839, the antarctic magnetic 

 expedition, under the command of Captain James Clark Ross, was fully 

 arranged ; and now, since its successful return, we reap the double 

 fruits of highly important geographical discoveries around the South 

 Pole, and a series of simultaneous observations at eight or ten magnetic 

 stations. 



* See the article on Terrestrial Magnetism in the Quarterly Review,* 

 1840, vol. Ixvi., pp. 271-312. 



