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Swan River, the latter being a most desirable station. We have not 

 alluded to the observatory at the Cape of Good Hope ; if however no 

 such establishment existed, the presence of Sir John Herschel would 

 ensure cooperation there, in any plan calculated to advance sci- 

 entific knowledge. Thus, altogether, there might be formed a most 

 extensive spread of stations, in which the principal expense would 

 consist in the purchase of the requisite instruments ; and the means 

 of establishing stations where the same facilities do not exist might 

 afterwards be taken into consideration. As it would be necessary 

 that, at all the stations, observations of the barometer, thermometer, 

 and of atmospheric phenomena should be made simultaneously 

 with the raagnetical observations, these would altogether form a 

 mass of valuable meteorological information which it would be 

 scarcely possible to collect by any other means. 



There is one point in M. de Humboldt's communication on which 

 we have not yet touched : the nature of the instruments best cal- 

 culated to attain the objects in view by the establishment of mag- 

 netical observatories. This is a subject on which it will be most 

 proper to enter fully when their establishment has been determined 

 upon j and we would recommend that then a Committee should be 

 appointed to investigate the subject, and that this Committee should 

 report to the Council of the Royal Society what instruments they 

 consider it would be most advisable to adopt at all the stations, and, 

 at the same time, give in an estimate of the expense that must be in- 

 curred for one complete set of such instruments. We may, however, 

 in the mean time, offer a remark on one apparatus referred to by 

 M. de Humboldt, that of M. Gauss. However well we may con- 

 sider this apparatus to be adapted for the determination of the course 

 of the regular diurnal variation, yet we apprehend that the great 

 weight of the needles employed would prevent their recording the 

 sudden and extraordinary changes in the direction of the magnetic 

 forces, which are, probably, due to atmospheric changes. Another, 

 and we conceive a very serious objection to this apparatus is, that 

 bars of the magnitude employed must have an influence so widely 

 extended, that there would be great risk of the interference of one 

 of these heavy needles with the direction of another, especially in 

 places where the horizontal directive force is greatly diminished, 

 unless the rooms for observation were placed at inconvenient di- 

 stances from each other. 



By referring to M. de Humboldt's letter, it will be seen that the 

 plan of observation so comprehensively conceived by him, has been 

 most powerfully and liberally patronized by the Governments of 

 France, of Prussia, of Hanover, of Denmark, and of Russia : indeed, 

 it is quite manifest that a plan so extensive in its nature must be 

 far beyond the means of individuals, and even of scientific societies 

 unaided by the governments under which they flourish. To sup- 

 pose, even without the example thus held out, that the Government 

 of this, the first maritime and commercial nation of the globe, should 

 hesitate to patronize an undertaking, which, independently of the 

 accessions it must bring to science, is intimately connected withna- 



