346 



TEACHINGS OF ELIE DE BEAUMONT. 



Elie de Beaumont's Generalisations. The following is De 

 Beaumont's view of his first five systems, including applications in 

 Great Britain for comparison with the details of Professor Phillips' 

 groups I. and II. : 



Geological Period of the 

 Convulsions. 



1. During the de-\ 

 position of the I 

 lower Palaeozoic V 

 strata, anterior to I 

 upper Silurians .) 



2. Posterior to the 

 upper Silurians, 

 anterior to Old 

 Red Sandstone . 



}$. After the CoaH 

 I strata and before [ 

 Rothetodtelie-f 

 gende . . ) 

 1 4 After the Coal i 

 II. / strata, and before > 

 the Zechstein . ) 



5. After the Coal] 

 strata, and before ( 

 the Biinter Sand- { 

 stein . . .1 



Effects Noted. 



Elevation of mountain 

 chains 



Great faults, and anti- 

 clinals 



Immense disruptions { 

 and faults of the coal. C 



Ditto . . ( 



Great disruptions 



Localities of some of the 

 Phenomena. 



Snowdon, Anglesea. 



Grampians, Lammer- 

 muirs, Cumbrians. 



From Derbyshire to 

 Northumberland along 

 the Western border of 

 Yorkshire, Malvern. 



Westphalia, Belgium, 

 Mendip, South Wales. 



Vosges and Black Forest, 

 from Basle to Mayence, 

 Faults in magnesian 

 limestone of northern 

 counties. 



Elie de Beaumont's Hypothesis. It has long been known in 

 mining countries that the faults take parallel directions, and some- 

 times two or more systems of dislocations, crossing in certain angles, 

 were found to be of different antiquity. That dislocations were in 

 some respects to be compared to the effects of earthquakes was also 

 well understood, but no one before De Beaumont appears to have 

 carried his notions of the coincidence between the lines of convulsion 

 and the direction of the great physical features of the globe so far as 

 to venture on the construction of a general system. This excellent 

 geologist believed that there is a constant dependence between the 

 direction of the dislocation and the geological epoch of its occurrence, 

 such that all the dislocations of the same age are parallel to one and 

 the same great circle of the sphere ; and that, in most instances, dis- 

 locations of different ages are parallel to different great circles, which 

 intersect one another at assignable angles owing to the shrinkage 

 and parallel crumpling of the earth's crust. This general hypothesis 

 is not to be tested by single or small dislocations. It must be 

 examined on a great scale, by means of very exact and numerous 

 data. The facts known are not clear and numerous enough to de- 

 monstrate this hypothesis ; and on the other hand there are not facts 

 to warrant the unconditional rejection of it. It is certainly founded 

 on. important data, and in several instances agrees well with observa- 

 tion. The principal difficulty of applying satisfactory tests to its 

 application, arises from the uncertainty of the exact date of many of 

 the most characteristic convulsions. We cannot positively tell 



