TIIANSACTIONS OF SECTION C. 697 



the first half of the present, forced the geology of their day into the very front rank 

 of the natural sciences, and made it perhaps the most conspicuous of tliem all in 

 the eyes of the world at large. Since that time, however, their successors have been 

 mainly occupied in completing the work of the great pioneers. The stratigraphical 

 geologists themselves have been almost wholly occupied in laying down upon our 

 maps the superficial outlines of the great formations, and workhig out their inter- 

 relationships and subdivisions. At the present day the young stratigraphical student 

 soon learns that all the limits of our great formations have been laid down iu 

 our maps and textbooks, and finds but little to add to the accepted nomenclature 

 of the time. 



Our palaeontologists, also, have equally busied themselves in working out the 

 rich store of the organic remains of the geological formations ; and the youthful 

 investigator soon discovers that almost every fossil he is able to detect in the field 

 has already been named, figured, and described, and its place in the geological 

 record more or less accurately fixed. 



In France, in Germany, in Norway, Sweden, and elsewhere, in Canada and in 

 the United States, work as thorough and as satisfactory has been accomplished, 

 and the local development of the great stratified formations and their fossils has 

 been laid down with detail and clearness. 



Many an unfledged but aspiring geologist, alive to these facts, and contrast- 

 ing the well-mapped ground of the present time with the virgin lands of the days 

 of the great pioneers, finds it hard to stifle a feeling of keen regret that there 

 are, nowadays, no new geological worlds to conquer, no new systems to discover and 

 name, and no strange and unexpected faunas to unearth and bring forth to the 

 astonished light of day. The youth of stratigraphical geology, with all its wonder 

 and freshness, seems to have departed, and all that remains is to accept, to 

 commemorate, and to round oflf the glorious victories of the dead heroes of our 

 science. 



But to the patient stratigraphical veteran, who has kept his eyes open to dis- 

 coveries new and old, this lull in the war of geological controversy presents itself 

 rather as a grateful breathing time ; the more grateful as he sees looming rapidly 

 up in front the vague outlines of those oncoming problems which it will be the 

 duty and the joy of the rising race of young geologists to grapple with, and to 

 conquer, as their fathers met and vanquished the problems of the past. He knows 

 perfectly well that geology is yet in her merest youth, and that to justify even 

 her very existence there can he no rest until the whole earth-crust and all its 

 phenomena, past, present, and to come, have been subjected to the domain of 

 human thought and comprehension. There can be no more finality in geology 

 than in any other science ; the discovery of to-day is merely the stepping-stone to 

 the discovery of to-morrow ; the living theory of to-morrow must be nourished 

 by the relics of its parent theory of to-day. 



Now if we ask what are these formations which constitute the objects of study 

 of the stratigraphical geologist, I am afraid that, as in Ihe case of the species of the 

 biologist, no two authorities would agree in framing precisely the same definition. 

 The original use of the term formation was of necessity lithological, and even now 

 the name is most naturally applied to any great sheet of rock which forms a com- 

 ponent member of the earth-crust ; whether the term be used specifically for a 

 thin homogeneous sheet of rock like the Stonesfield slate, ranging over a few 

 square miles ; or generically, for a compound sheet of rock, like the Old Red 

 Sandstone many thousands of feet in thickness, but whose collective lithological 

 characteristics give it an individuality recognisable over the breadth of an entire 

 continent. 



When Werner discovered that the 'formations' of Saxony followed each 

 other in a certain recognisable order, a second characteristic of a formation 

 became superposed upon the original lithological conception — namely, that of de- 

 terminate ' relative position.' And when William Smith proved that each of the 

 formations of the Enghsh Midlands was distinguished by an assemblage of organic 

 remains peculiar to itself, there became added yet a third criterion — that of the 

 possession of 'characteristic fossils.' 



