NERBUDDA DISTRICT. 257 



With reference to this last question, namely the age of the faults, it 

 must of course be remembered that relative age only is considered : and 

 that when we speak of one fault as of a different age from another, we 

 only mean that after the former, and before the latter, a cycle of geolo- 

 gical events ran its course ; some area had, from one of denudation, 

 become one of deposition, beds had been formed, consolidated, disturbed 

 &c. Whenever there is evidence, as in the examples adduced, to show that 

 this was the case, we speak of the faults as of different geological 

 ages, irrespective of the absolute ages, or position in the geological scale, 

 of the two formations, from the examination of which we derive the 

 proof. 



Those who may remember the theory of the synchronism of parallel 

 mountain chains, proposed by M. E. de Beaumont, cannot fail, while 

 perusing the foregoing pages, to have remarked, that many of the condi- 

 tions necessary for the investigation and application of that theory are 

 here exceptionally well developed. The theory asserts that those vast 

 movements which caused fissures in the earth's crust, the direction of 

 which fissures is now marked by mountain chains, acted, wherever pro- 

 duced at the same time, in lines parallel in direction, even when they took 

 effect on portions of the surface far apart from each other. And that, 

 therefore, mountain chains, and great lines of dislocation, whether close 

 to each other, or in the most distant parts of the earth, where parallel 

 in direction, may be referred to the same, or synchronous, internal move* 

 ments as their cause. 



It is needless to point out how important a step towards establishing 



European equivalents for our Indian rock systems we should have made, 



could we fix the age of such movements as that which produced the 



Vindhyan range, relatively to that of some of the twenty geological dates 



assigned by M. de Beaumont to the principal systems of mountains and 



great fault lines of Europe. 



M. de Beaumont has already himself offered some suggestions on this 



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