1837.] 



Report on Terrestrial Magnetism. 



28g 



Bight of Benin as a desirable station; bat the insalubrity of the cli- 

 mate and other circumstances prevent our recommending its adoption. 



M. de Humboldt has not referred to any station in our West 

 Indian colonies, but we consider that circumstances point to Ja- 

 maica as a station where it is very desirable that accurate mag- 

 netical observations should be made. It is generally considered \ h\it 

 the variation there has, for a very long period, undergone but little 

 change ; and, on this account alone, it would be very desirable to as- 

 certain, with precision, the amount of the variation, so that hereafter 

 the nature of the changes it may undergo may be accurately determined. 

 Its position also, with reference to the magnetic equator, is one which 

 would recommend it as a magnetical station.* 



Although M. de Humboldt has not adverted to any other point besides 

 Ceylon in our Indian possessions, yet no doubt he would, with us, con- 

 sider it desirable that observatories should be established at different 

 points on the continent of India; and it appears to us that Calcutta 

 and Agra are in positions well adapted for the purpose. As, however, 

 there is an Astronomical Observatory established at Madras, there 

 would be greater facility in obtaining magnetical observations there 

 than at places where no such establishment exists. t We feel assured 

 that the East India Company, which has shewn so much zeal and libe- 

 rality in the promotion of scientific inquiry, and such a desire for the 

 advancement of scientific knowledge in the extensive possessions under 

 its controul, would afford its powerful assistance in the establishment 

 of observatories for the investigation and determination of the laws of 

 phenomena intimately connected with navigation, and, consequently, 

 with the commercial prosperity of our country. 



We consider, also, that Gibraltar and some one of the Ionian Islands 

 are very desirable stations for the establishment of permanent magne- 

 tical observatories ; and, to come nearer home, that such observatories 



* Mr. Pentland, who has been appointed Consul-General to the Republic of Bolivia, 

 having, since the Baron de Humboldt's letter was referred to us, offered his earnest 

 co-operation in the objects contemplated in that letter, we cannot hesitate, now that 

 this has been communicated to us, to recommend that an offer so liberal should be mado 

 available to science. If accurate magnetical observations were made at some station on 

 the elevated table-land of Mexico, and simultaneously at another not very distant station, 

 nearly at the level of the sea, we consider that they would determine points relative to 

 the influence of elevation on the diurnal variation, the dip and intensity, respecting 

 which our information is at present, to say the least, extremely deficient. 



+ It will be observed by the preceding article that the zealous Astronomer of Madras 

 has needed no other incentive to carry on these investigations than the impulse of 

 his own ardent mind. With a munificence highly creditable to a private individual, 

 he has offered to supply the necessary apparatus to any persons willing to under- 

 take a series of experiments, and we hope that by this means several magnetic stations 

 will be established in S. India. Mr. Taylor is at this time on a scientific expedition to 

 the southward, where he has appointed to meet Mr. Caldecott, Astronomer to the new 

 Observatory at Trevandrum, to concert with that gentleman plans for the above purpose fl 

 as well as to make magnetic experiments oa the route.— Editor Madras Journal. 



