THE 



QUARTERLY JOURNAL 



OF 



SCIENCE, LITERATURE, AND ART. 



On M. Hansteeris recent Magnetic Observations in Siberia. 



In a Letter to Professor Renwick of New York. 



Somerset House, July 20, 1829. 

 My dear Sir, 



I received a few days ago a letter from Professor Han- 

 steen of Christiania, dated from Irkutsk in Siberia, in April last. 

 M. Hansteen is travelling, as you know, at the expense of his 

 King, and with the permission of the Emperor of Russia, for the 

 purpose of observing the Magnetic Dip, Variation, and Inten- 

 sity, over the whole of the north of Europe and of Asia; and 

 of comparing the actual phenomena with the system of terres- 

 trial magnetism propounded by himself, in his celebrated trea- 

 tise entitled " Magnetismus der Erde." 



The observations that M. Hansteen has already made in the 

 first year of his undertaking, and the conclusions which they 

 establish in regard to the directions assumed by the isodynamic 

 curves, or curves of equal magnetic intensity, are in the highest 

 degree curious and important. In the letter with which he 

 has favoured me, he has taken the trouble to communicate his 

 observations in full detail, and has expressly permitted me to 

 make every use of them that I may think proper, " especially 

 when it may encourage to new undertakings and accordingly 

 forward the science." Having been requested by you to super- 

 intend the construction in this country of a part of the mag- 

 netic instruments, designed for the expedition now preparing 



JULY— SEPT., 1829. B 



