Geographical Collections. 35 



of this expedition ; and M. Litke proposed to carry on a series of observations on 

 the declination of the magnetic needle, and on the pendulum. M. Mertens re- 

 marked that even a limited residence upon this island might be very productive 

 to the collections of the Academy, and particularly to the herbarium, if the Aca- 

 demy would think fit to join to the expedition a naturalist, who might also carry 

 on researches upon the diiferent tribes of acalepha and mollusca swimming freely 

 in the ocean, — an opportunity which was rarely offered to Russian travellers ; and 

 he further offered his services to the Academy, which were accepted with pleasure. 

 The expectations of M. Mertens have been fully realized in the result of the 

 expedition ; and since his return, he has undertaken a series of publications on the 

 collections of natural history which were made during the voyage. He has alrea- 

 dy begun the first number of his Ftici. 



De Humboldfs Observations on the Inclination of the Magnetic Needle 



At the sitting of the Academy of Sciences of Paris, on the 28th June last, a 

 memoir by M. de Humboldt was read, on the inclination of the magnetic needle 

 in the north of Asia, accompanied by corresponding observations on the horary 

 variations in Europe. These investigations have been conducted during the author's 

 last journey. He has taken the greatest care in the choice of the places in which 

 he made the observations necessary to appreciate the intensity of magnetic forces. 

 Those which he had conducted in Peru, Mexico, at Tobolsk, on the banks of the 

 Obi, and in many parts of the old world, during the perambulation of 12600 

 miles, supplied him with comparative data. M. Hansteen, a highly distinguish- 

 ed observer, had very recently traversed almost the same district as the author of 

 this memoir, and thus their observations were mutually checked. M. de Hum- 

 boldt had not yet learned M. Hansteen's results ; but M. Kupfer, who had ex- 

 amined them, found that they agreed generally with those detailed in this me- 

 moir. M. de Humboldt, since his return to Berlin, has made daily observations 

 on the horary variations of the compass, in an observatory which does not contain 

 a particle of iron. But daily observations at the moment of maximum and mi- 

 nimum, were not M. de Humboldt's only object in having such an observatory. 

 A series of observations, not less important, has been conducted therein on the 

 successive variations in the twenty-four hours, taken every half hour. The author 

 has also established simultaneous observations in different parts of the globe. He 

 has engaged correspondents in ten or twelve very distant places, between the ex- 

 tremes of which there is not less than 120 degrees of longitude, as from Kasan 

 to Marmoto, in the cordillera of Choco. Observations will also be made in places 

 whence we have hitherto had little hope of obtaining them ; for instance, they 

 will be carried on at Pekin, in the house of the Russian missionaries. Through 

 the assiduity of M. de Humboldt, observations will also be made at the bottom 

 of mines ; that is to say, in places where the temperature is almost invariable, 

 and consequently where the variation will be beyond the influence of the diurnal 

 changes of temperature which take place at the surface. 



Voyage to the: Antarctic Sea. — (Extract from a letter from Dr. Dekay, dated 

 New York, May 16th 1830.) — When it was proposed, about four years ago, to 

 fit out an expedition to the South Sea, Mr. Reynolds, one of the principal authors 

 of the project, was directed by the Secretary of the Marine Department, to col- 

 lect what information he could obtain from the whalers who frequent the southern 

 parts of th« Atlantic and Pacific Oceans. 



In the report which he gave on this subject, Mr. Reynolds showed that the 

 number of vessels employed in these latitudes in fishing whales or seals, amounts 

 to 200 ; each ship of 725 tons occupying twenty -nine months in the voyage, and 

 bringing home a cargo of 1700 barrels. The whaleis who have penetrated into 

 low southern latitudes are very reserved as to any thing connected with their dis- 

 coveries ; islands have been visited and revisited by many of them a score of years 

 before they have been known to others. Moreover, they will give no information 

 except on the express condition that it shall be subservient to a national expedition. 



