13 



themselves * When the Men of the PoHshed Stone Age appeared' 

 they were accompanied by the domestic horse and dog, and agricul- 

 ture was well developed among them. They were also contem- 

 porary with a fresh set of wild animals ; the Mammoth and the 

 Woolly Rhinoceros are gone ; tho Cave Lion and Cave Bear have 

 disappeared, " the two sets of men, their remains, and their animal 

 companions are sharply and definitely separated by a complete 

 gap. " The deposits of the Mammoth age, and it would seem of the 

 Reindeer Age as well, are covered with beds of yellow earth, brick 

 earth, and earth with angular stones, which antedate the later 

 stone age. These deposits are of the same nature with the super- 

 ficial gravel, soils, and loess to be found resting on the Pleistocene 

 deposits everywhere in the northern hemisphere, and which have 

 poured into all the old caverns of the Palaeocosmic Age." No 

 Mammoth remains occur above such deposits. 



What happened between the two great Stone Ages to cause this 

 " gap ? " Had it anything to do with the disappearance of the 

 Mammoth ? 



I am now crossing the borders and entering the Debateable Land, 

 where little is certain, and where every point brought forward will 

 'give ample opportunities for discussion, of which I hope many will 

 avail themselves. 



You must know that among students of geology there are two 

 schools of thougut, including what are termed Uniforrnitarians and 

 Catastrophists. The former, with Sir C. Lyell at their head, believe 

 that physical changes have always been going on in the world in 

 much the same way as they are going on now ; the same agents at 

 work — rivers, rain, frost, and fire ; and varying little if at all from 

 their present normal rate. It is they who make such enormous 

 demands for past time, as they must necessarily do in order to 

 account for such results at a slow rate. The Catastrophists on the 

 other hand refuse to be bound down in this way; they do not deny 

 the similarity or even the identity of the agencies of change, but 

 they hold that these agencies have in old times acted occasionally 

 with far greater violence and intensity than they ever do at 

 present. And there is a great deal to be said in favour of their 

 views. 



Like all enthusiastic partizans, adherents of both sides are apt to 

 make very positive and sweeping assertions occasionally, against 

 which it is necessary that we should be on our guard. You may 

 know them by their use of such phrases as — " It can easily be 

 shown, &c." " It is a well-established fact, &c." " This theory is 

 now exploded, &c., &c. Several "exploded" theories have lately 



• The Statement refers only to the Men of the River Drifts, not to the Cave-men 

 •who may possibly be represented now by the Eskimos. 



