1867.] Sir Charles Lyell and Modem Geology. 13 



Charles Lyell has brought forward several arguments, especially, 

 (1) that " several of the great lakes are by no means in the position 

 which they ought to have taken had they been scooped out by the 

 pressure and onward motion of the extinct glaciers ; " (2 ) that lakes 

 of the first magnitude do not occur " in several areas where they 

 ought to exist if the enormous glaciers which once occupied those 

 spaces had possessed the deep excavating power ascribed to them; " 

 (3) that the presence of patches of preglacial freshwater formations 

 in some Alpine valleys, e.g. on the: borders of the Lake of Zurich, 

 prove that some of the lakes must have existed before the glacial 

 period. 



Sir Charles Lyell seems, however, in this instance, more 

 fortunate in opposition than in proposition. He has shown that the 

 " erosive power of ice was not required to produce lake-basins on a 

 large scale," by means of the preglacial lacustrine formations of the 

 Lake of Zurich. Some other cause must then have produced 

 them if glaciers did not excavate them, and Sir Charles Lyell 

 suggests " unequal movements of upheaval and subsidence." This 

 theory ought to be capable of proof or refutation by geological 

 surveyors, and no doubt it will sooner or later be submitted to the 

 test ; but until that is done little more can be said about it, than 

 that it does not enlist in its favour the sympathies of those who 

 have been trained by Sir Charles Lyell himself to the application 

 of the doctrine of Uniformity. 



The ' Antiquity of Man' was published as a resume of the 

 evidence which has recently been accumulated in favour of 

 the contemporaneity of Man with certain extinct Mammalia. It 

 was avowedly a compilation ; but it contains a large mass of matter 

 drawn from a variety of sources, and tending to strengthen the 

 evidence in favour of Man having existed on the earth in Post- 

 pliocene times. Perhaps not even the ' Principles ' exhibits 

 more clearly the author's wonderful faculty of "assimilation," as 

 Dr. Fitton called it, of turning anything and everything into good 

 geology. But it is unnecessary for us to discuss this subject at 

 greater length, except incidentally, as being one of the last dis- 

 coveries bearing on a view of the succession of life in time which 

 Sir Charles Lyell has persistently maintained ever since the com- 

 mencement of his distinguished career. 



Negative evidence has always been a battle-ground for geologists 

 holding opposite views, and it is only of late years that its use has 

 fallen considerably in estimation. The experience of the last half- 

 century has taught geologists that it is highly unphilosophical, and 

 positively unsafe, to assume that any class of organisms has not 

 existed at any particular period, or that there is a total break in the 

 succession of life on the earth at any horizon in the geological 

 scale, merely because we have no positive evidence in proof of the 



