34 



explain such phenomena as these. They appear to me only 

 resolvable on the supposition that crystalline or polar forces 

 acted on the whole mass in given directions and with adequate 

 power." 



In the Geological Report of Cornwall and Devon, Sir H. de la 

 Beche remarks, — 



(C When we regard the prevalence of the great divisional planes 

 in particular directions crossed by others nearly at right angles 

 to them, producing solids to a certain extent symmetrical, and 

 consider the mineral modifications which the sedimentary beds 

 have generally undergone since they were deposited, we are led 

 to suspect not only that the lamination planes, commonly termed 

 cleavage, are, as has been supposed by some authors, due to polar 

 forces, but also that the great divisional planes have been equally 

 caused by them, as has been considered probable by others." 

 " Although the direction of the present magnetic meridian in the 

 district may be merely temporary, and the proximation of so 

 many great divisional planes to it therefore accidental, still their 

 great prevalence, both in the igneous (crystalline) rocks and 

 sedimentary deposits, in that direction, leads us to suppose that 

 polar forces may have considerably governed the arrangements 

 of the component matter of the rocks they traverse during con- 

 solidation .... If we require a constant tendency of such polar 

 forces to arrange the component matter of rocks during consoli- 

 dation in given areas, we can the more readily account for the 

 frequency of nearly similar directions in the great divisional 

 planes of rocks of different ages." 



These observations are quoted here merely to show the striking 

 coincidence of independent investigations with which the writer 

 was totally unacquainted during his researches in America; but 

 they clearly prove the universality of the polar lamination. 



During a recent examination of the metalliferous deposits and 

 primary rocks of England and Ireland, we found the old lami- 

 nation of the United Kingdom, on an average, a few degrees east 

 of north, and the new lamination intersecting it obliquely, in a 

 direction approaching the present magnetic meridian. See Plate 

 IX. The same kind of polar structure has been observed in 

 coal beds in all countries. 



The meridional lamination has been observed from Morocco, in 



