74 COSMOS. 



The instruments were dispatched in 1839, and the observa- 

 tions were begun at Toronto and in Van Diemen's Land in 

 1840, and at the Cape in 1841 (See Sir John Herschel in the 

 Quarterly Review, vol. Ixvi, 1840, p. 297, and Becquerel, 

 Traite d* Electricite et de Magnetisme, t. vi, p. 173). By the 

 careful and thorough elaboration of these valuable observa- 

 tions, which embrace all the elements or variations of the 

 magnetic activity of the earth, General Sabiiie as superin- 

 tendent of the Colonial observatories, discovered hitherto 

 unrecognized laws, and disclosed new views in relation to the 

 science of magnetism. The results of his investigations were 

 collected by himself in a long series of separate memoirs (Con- 

 tributions to terrestrial magnetism) in the Philosophical 

 Transactions of the Royal Society of London, and in separate 

 works, which constitute the basis of this portion of the 

 Cosmos. We will here indicate only a few of the most im- 

 portant (1) Observations on days of unusual magnetic disturb- 

 ances (storms) in the years 1840 o*kf 1841, pp. 1 107, and as 

 a continuation of this treatise, magnetic storms from 1843 

 1845 in the Phil. Transact, for 1851, pt. i, pp. 123-139, 

 (2) Observations made at the Magnetical Observatory at Toronto 

 1840,1841, andl842(43 39'KLat, and 8141'W. Long.)vol.i, 

 pp. xiv xxviii; (3) The very variable direction of magnetic de- 

 clination in one-half of the year at Long wood House, St. Selena 

 (15 55' S. Lat., 8 3' W. Long.), Philosophical Transactions 

 for 1847, pt. i, p. 54; (4) Observ. made at the Magn. and Meteor. 

 Observatory at the Cape of Good Hope 18411846; (5) Observ. 

 made at the Magn. and Meteor. Observatory at Hobarton 

 (42 52' S. Lat., 145 7' E. Long.) in Van Diemen's Land and 

 the Antarctic expedition, vol. i and ii, (1841 1848) ; on the se- 

 paration of the eastern and western disturbances, see vol. ii, pp. 

 ix xxxvi; (6) Magnetic phenomena within the Antarctic polar 

 circle inKergueleris and Van Diemen's Land (Phil. Transact. 

 for 1843, pt.'ii, pp. 145 231) ;(7) On the isoclinal and isody- 

 namic lines in the Atlantic Ocean, their condition in 1837 

 (Phil. Transact, for 1840, pt. i, pp. 129155); (8) Basis of a 

 chart of the Atlantic Ocean which exhibits the lines of 

 magnetic variation between 60 N. Lat. and 60 S. Lat. for 

 the year 1840 (Phil. Transact, for 1849, pt. ii,pp. 173233) ; 

 (9) Methods of determining the absolute values, secular change, 

 ind annual variation of the magnetic force (Phil. Transact, f&t 



