On the Elevation of Mountain Ranges. 291 



the two places, and that it acts in the same manner as the local at- 

 traction of iron mines in turning the needle from the direction of the 

 pole. 



At present the direction of the magnetic line differs from any of 

 our mountain ranges ; but that it may some time have been the same 

 is not irrational to conjecture, since during less than half a century 

 (the seventeenth) its course so greatly varied, that the whole extent 

 of the Atlantic intervened between its places at the first and last ob- 

 servations. What in the course of ages have been the causes to di- 

 minish the intensity of the power, if it be diminished, or repress it, 

 if it only slumber ; what are the laws of its variations, and what phe- 

 nomena it may yet present, are subjects far beyond the limits of con- 

 jecture. At least there, more than elsewhere, are indications of a 

 stupendous, although quiescent force, to fix the attention of the phi- 

 losopher; and future observations may open a new era for science, 

 if any connection in results can be demonstrated, tending to the dis- 

 covery of the action of a principle which has been considered one of 

 the mysteries of nature " never to be searched out by man." Wide 

 as appear the deviations, and far from being systematized as are 

 the facts recorded, it is not to be supposed that the principle is out 

 of harmony with the economy of nature, whose laws are as fixed in 

 the wanderings of a comet as in the revolutions of a satellite. And 

 whatever be the anomalies of a few years' observations, the persua- 

 sion cannot be resisted, that in the recorded history of many ages 

 would be seen in this, only another instance of beautiful simplicity in 

 the mechanism of nature. 



That the elevations in many mountainous districts have proceeded 

 from local causes, and not from the action of any such constant prin- 

 ciple, is not to be doubted ; and these, it is supposed, present suffi- 

 ciently marked characteristics to be distinguished by accurate ob- 

 servers. Such perhaps are the Alps, the Highlands of Scotland, 

 and though several ranges of Europe tend towards the opposite or 

 Siberian magnetic pole, yet they are in general limited or broken 

 up ; and the most careless and unscientific would naturally refer 

 them to agencies, combined or acting differently from those which 

 produced the great mountain ranges of America. 



