President'' 's Address. 



13 



peculiar and beautiful effects of the construction of a glacier 

 in its descent towards the sea. Above, all is smooth and far 

 spread out; a little lower down, it becomes more crumpled 

 up as the space becomes more limited, and you can see that 

 the point of maximum motion is in the centre. Further 

 down, the crumpling is increased, until, before it reaches its 

 destination, the crumples have become ten thousand spikes, 

 which, seen under a meridian sun, and with the help of good 

 telescopes, appeared as if the bayonets of ten thousand 

 soldiers were raised on high, and ready to be lowered to op- 

 pose an equal host. 



I shall now only allude to one or two points of interest in 

 regard to the lavas of Iceland which are germane to our 

 present subject, leaving the description of the Geysers, and 

 their mineralogical and chemical teachings, to another time, 

 when I hope to take the opportunity of showing how many 

 questions they may solve in geology which hitherto have 

 been unanswered. 



The geologist, on first setting foot on Iceland, is at once 

 struck with the certainty that all has been of volcanic origin : 

 black ashes, bleak mountain ranges, and rude irregularity of 

 surface, convince him that not long back in the geologic 

 record, this Haven of Eeykjavik was surrounded by the most 

 violent eruptions of fire. But as he journeys towards the 

 interior of the island, he finds that he can differentiate at 

 once between the outpourings of lava as it flowed molten 

 from the crater, and those other formations which were truly 

 subaqueous. 



As my attention was particularly directed to the ap- 

 pearance of subaqueous formations, in the hope of detecting- 

 dressed surfaces, which would be geological chronometers to 

 indicate the age of irruptions, in which I failed ; I was led to 

 remark how very easily one may be led astray by finding so 

 many parallel and comparatively smooth surfaces lying close 

 in contact with many tortuous shapes. After a careful exami- 

 nation of many hundred instances, — for they are the most 

 common phenomena in the journey to the Geysers, — though 

 curiously overlooked by former travellers, I was led to the 

 conclusion, that they w r ere merely plications or folds in the 



