16 EEfORT — 1881. 



now, -while the mean temperature of the coldest month would be lowered 

 20°. We thus get something like a date for the last glacial epoch, and 

 we sec that it was not simply a period of cold, but rather one of ex- 

 tremes, each beat of the pendulum of temperature lasting for no less than 

 21,000 years. This explains the fact that, as Morlot showed in 1854, 

 the glacial deposits of Switzerland, and, as we now know, those of Scot- 

 land, are not a single uniform layer, but a succession of strata indicating 

 very different conditions. I agree also with CroU and Geikie in thinking 

 that these considerations explain the apparent anomaly of the co-existence 

 in the same gravels of arctic and tropical animals ; the former having 

 lived in the cold, while the latter flourished in the hot, periods. 



It is, I think, now well established that man inhabited Europe during 

 the milder periods of the glacial epoch. Some high authorities indeed 

 consider that we have evidence of his presence in pre-glacial and even 

 in Miocene times, but I confess that I am not satisfied on this point. 

 Even the more recent period carries back the record of man's existence 

 to a distance so great as altogether to change our views of ancient 

 history. 



Nor is it only as regards the antiquity and material condition of man 

 in prehistoric times that great jjrogress has been made. If time 

 permitted I should have been glad to have dwelt on the origin and 

 development of language, of custom, and of law. On all of these the 

 comparison of the varioias lower races still inhabiting so large a portion 

 of tlie earth'.s sm^face, has thrown much light ; while even in the most 

 cultivated nations we find survivals, curious fancies, and lingering ideas ; 

 the fossil remains as it were of former customs and religions, embedded 

 in our modern civilisation, like the relics of extinct animals in the crust 

 of the earth. 



In geology the formation of our Association coincided with the appear- 

 ance of Lyell's ' Principles of Geology,' the first volume of which was 

 published in 1830 and the second in 1832.. At that time the received 

 opinion was that the phenomena of Geology could only be explained 

 by violent periodical convulsions, and a high intensity of terrestrial 

 energy culminating in repeated catastrophes. Hutton and Playfair had 

 indeed maintained that such causes as those now in operation, would, if 

 only time enough were allowed, account for the geological structure of 

 the earth ; nevertheless the opposite view generally prevailed, until Lyell, 

 with rare sagacity and great eloquence, with a wealth of illustration 

 and most powerful reasoning, convinced geologists that the forces now 

 in action are powerful enough, if only time be given, to produce result.^ 

 quite as stupendous as those which Science records. 



As regards stratigraphical geology, at the time of the first meeting of 

 the British Association at York, the strata between the carboniferous lime- 

 stone and the chalk had been mainly reduced to order and classified, chiefly 

 through the labours of William Smith. But the classification of all the 



