ANNIVERSARY ADDRESS OF THE PRESIDENT. lix 



if, either in my previous comments or those which may follow, I may 

 appear to have spoken in a tone of severity, I sincerely hope that I 

 may not be thought to have been uninfluenced by a spirit of candour, 

 or a due feeling of respect, which no one can entertain more sincerely 

 than myself, for the distinguished author of this theory. 



I would also make another prefatory remark. This theory at pre- 

 sent is professedly in a pi^ovisional state, although its author, in dis- 

 cussing it, may not unfrequently, and perhaps not unnaturally, have 

 adopted a tone which might imply a forgetfuluess of the fact. Con- 

 sequently, M. de Beaumont ought to be allowed to modify his theory 

 as circumstances may require without the charge of inconsistency, 

 unless he should forfeit his right to do so by a too pertinacious ad- 

 herence to his first announcements. It is not a theory to be at once 

 either entirely adopted or utterly rejected, but is one, on the con- 

 trarjr, which may admit of great modifications without the sacrifice 

 of its essential identity, or of that honour which its author may here- 

 after claim from it. I make these observations that my own views 

 respecting it may not be misunderstood, and in order that the objec- 

 tions I may urge against the Theory of parallelism may be con- 

 sidered as against the precise form which it has assumed at the pre- 

 sent moment, rather than against its essential principles, or some 

 modified form which it may hereafter assume in accordance with 

 them. 



In the following sketch of the geological structure of the districts 

 to which I have above alluded, I shall be principally indebted to the 

 able researches of Professor Sedgwick and Sir R. I. Murchison, with 

 the more recent and admirable investigations of the Geologists of the 

 Ordnance Survey. 



In the amiexed table, M. de Beaumont's European systems, with 

 the exception of one (that of Vercors), the geological date of which re- 

 mains undetermined, are given in chronological order, as are also the 

 sedimentary formations in the same column. The date of each system 

 with reference to the whole series of the formations is thus presented 

 at once to the eye. In the second column I have given the orienta- 

 tion of each system. The orientation of a great circle of reference 

 is, as we have seen, different for different points of it ; and, there- 

 fore, to compare the orientations of these different great circles, it is 

 necessary to refer them all to one common point or centre of reduc- 

 tion. Had they all passed through one and the same point, that 

 point might have been conveniently chosen for the purpose ; but 

 such not being the case, it was necessary to select some independent 

 point to which all \\\% great circles of reference might be reduced, by 

 describing through it great circles respectively |;ffr«//e^ to the former 

 in the sense previously explained * . The author has made such re- 

 ductions to several different points. The one here selected is Binger- 

 loch, on the Rhine, which is centrally situated with reference to the 

 European systems. In the third column I have given, though some- 

 what vaguely, most of the principal localities or countries in which 

 each system is considered to have been recognized. 

 * Supra, page xliii. 



