248 On the former Changes of the Alps. 



The third scene, therefore, exhibited the sands and pebbles of 



the genial period thrown up into mountains on the flanks of the 



chain, the peaks of which were probably covered for the first 

 time with snow, and from the openings of which, whether pro- 

 truding to the sea-shore or into deep fiords or bays, glaciers and 

 their moraines advanced, from which icebergs or rafts were 

 floated away as suggested. 



In concluding Sir Roderick thus expressed himself: — ^' Having 

 thus now conducted you rapidly through the most prominent 

 changes which the Alps have undergonCj from the first period 

 when they had emergedj probably as an archipelago of low islands 

 in a tropical climate, to that epoch when the animals and plants 

 hving upon them indicated a Mediterranean temperature, and then 

 to that Arctic period, the conditions of which I have just been 

 discussing, I have no longer to call for your assent to any infer- 

 ences of the geologist, which all of you are not perfectly compe- 

 tent to understand. 



" To convert the Alps of the earliest glacial period into the 

 Alps of the present day, you have only to figure them to your- 

 selves, as raised 2000 or 3000 feet above the altitude which they 

 are supposed to have in the diagram last exhibited. All their 

 main features remaining the same, you would then have before 

 you, the present Alps and their valleys, irrigated by lakes and 

 rivers instead of bays ; and in place of the waters sketched in 

 beyond them as in the painting, with ice-bergs floating upon 

 them, you will then have dry mounds of gravel, sand^ and blocks 

 which were accumulated under the former waters ; such, in a 

 word, as now constitute low hills and valleys and all the richest 

 land of Switzerland and Bavaria, where man has replaced the 

 rhinoceros and turtles of one period, and the icebergs of another. 

 You who have not visited this noble chain, and who wish to 

 judge of its gorges, peaks, and precipices, have only to consult 

 the views of our associate Brockedon, in order to have nature in 

 her present mood, brought in the most telling manner before you. 

 But those of you who really wish to grapple with the geological 

 wonders of former days, may look at the flanks of the Rigi from 

 the lake of Lucerne, whence, even from the deck of the rapidly 

 passing steamer, you will see how that great pile of pudding- 

 stone, every pebble of which has been derived from rocks in the 

 chain more ancient than itself, has been lifted up from beneath 

 the waters in the manner represented ; whilst if you continue 

 the same traverse up the Lake to Altorf, you will pass by numer- 

 ous extraordinary folds and breaks of the secondary limestones, 

 and of the older Tertiary or Nummulitic rocks. Such a doub- 

 ling or crumpling up of these strata, you may then perchance 

 agree wiih me in thinking, was in a great measure the result of 

 lateral pressure between two great masses; the crystalline centre 

 of the chain upon the south^ and the newly upraised deposits on 



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