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more, poplar, elm, magnolia, sequoia sassafras viburnum, and 

 other trees of temperate zones. We are here confronted with 

 one of the most interesting problems of geology. How did 

 those plants contrive to flourish in a region where no trees 

 can now exist, and where there is for many months a total 

 absence of sunlight. Is it possible that the ice which now 

 covers the two poles is a mere accidental occurrence in time. 

 It would seem that at one time the North Pole at all events 

 enjoyed light, sunshine, and warmth. We know that the ice 

 which now is confined to the Polar regions at one time extended 

 as far south as the middle of France, and that there came a 

 warm interval when the lion, rhinoceros, elephant, crocodile, 

 and other tropical animals spread themselves over Europe as 

 far north as Scotland, and that the cold returning these ani- 

 mals were destroyed or driven south again. I am well aware 

 that certain physicists explain these matters some by referring 

 to the precession of the equinoxes and others by supposing a 

 change in the axis of rotation ; but the changes due to the 

 former cause will not account for the presence of coal plants 

 in Northern Greenland, and the most eminent mathematicians 

 reject the possibility of the latter. Sir William Thomson 

 says that the axis of the earth cannot have been changed 

 without " such enormous transposition of matter on the earth's 

 surface or else such distortions of the whole solid mass as 

 would present far greater difficulties of another kind than 

 those with which we have had to deal." Whilst all these 

 changes were going on in the Northern Hemisphere what was 

 the state of things in the Southern ? Is there any evidence 

 of a Glacial Period in Australia? I observe that this ques- 

 tion is being discussed in our contemporary Societies. Some 

 light may be thrown on this problem when we become better 

 acquainted with the geology of the Antarctic. 



Again what is the present state of the volcanic forces of the 

 Antarctic ? Ross saw Mt. Erebus in active eruption, some of 

 the officers of the Terror thought they saw smoke issuing from 

 the lofty peaks of Louis Plullipe Island, some of the American 

 officers were of opinion that they saw volcanoes, and one 

 American whaling captain reported that on visiting Deception 

 Island, one of the S. Shetlands, he found 13 craters in active 

 eruption. An active crater is supposed to exist on Kergu- 

 len, and we have had recent experience of the New Zealand 

 volcanoes. Remembering that Iceland is the theatre of vast 

 volcanic forces and that Jan Mayen is still active within the 

 Arctic Circle some theorists have been led to suppose that the 

 earth's crust thins out at the Poles. 



Geologists will look forward with great interest to the pros- 

 pect of further exploration in the Antarctic. 



It is not my intention to describe the Flora and Fauna of 



