Proceedings of the British Association. 335 



Report of the Committee (Sir J. Herschel, Mr. Whewell, Mr. 

 Peacock and Prof. Lloyd,) appointed to draw up plans of scientific 

 cobperation relating to the subject of terrestrial 7nagnetism. In 

 consequence of the measures adopted as detailed in the last re- 

 port of this committee, a very extensive system of corresponding 

 magnetical observations has been organized, embracing between 

 thirty and forty stations in various and remote parts of the globe, 

 provided with magnetometers and every requisite instrument, and 

 with observers carefully selected, and competent to carry out, at 

 most, if not all the stations, a complete series of' two-hourly ob- 

 servations, day and night, during the whole period of their re- 

 maining in activity, together with monthly term observations, at 

 intervals of two minutes and a half. Of these observatories, that 

 at Dublin, placed under the immediate superintendence of Prof. 

 Lloyd, has been equipped and provided for by the praiseworthy 

 liberality and public spirit of the University of that metropolis, — 

 those at Toronto, the Cape of Good Hope, St. Helena, and Van 

 Diemen's Land, as also the two itinerant observatories of the An- 

 tarctic Expedition by the British Government, — those of Madras, 

 Simla, Sincapore and Aden, by the Hon. East India Company ; 

 to which are to be added ten stations in European and Asiatic 

 Russia, and one at Pekin established by Russia, — two by Austria, 

 at Prague and Milan, — two in the U. States ; viz. at Philadelphia, 

 by the Girard College, and at Cambridge by the American Acad- 

 emy, — one by the French government at Algiers, — one by the 

 Prussian, at Breslau, — one by the Bavarian, at Munich, — one by 

 the Spanish, at Cadiz, — one by the Belgian, at Brussels, — one by 

 the Pasha of Egypt, at Cairo, and one by the Rajah of Travan- 

 core, at Trevandrum, in Lidia. In addition to this list, it has re- 

 cently also been determined, at the instance of the Royal Society, 

 by the British Government, to provide for the performance of a 

 series of corresponding observations, both magnetic and meteoro- 

 logical, at the Royal Observatory at Greenwich, under the able 

 superintendence of the Astronomer Royal. At Hammerfest also, 

 in Norway, negotiations have been for some time carrying on for 

 establishing an observatory of a similar description, in which Mr. 

 Hansteen has taken an especial interest. A great number of mag- 

 netic and other instruments available for this service, it appears 

 have been left at Kaafiord, by M. Gaymard, acting for the " Com- 

 mission Scientifique du Nord," under the direction of the French 



