POLAR ICE-CAPS AND SEA LEVELS. 337 



They went over floating ice, and only succeeded in 

 getting over something like 30 miles ; for floating 

 ice is exceedingly rough and hummocky in charac- 

 ter, making the passage difficult for travellers. All 

 we know then about the North Pole is that it is 

 probably floating ice. There is also very strong, if 

 not absolute evidence to show that there is great 

 freedom for currents to flow under the ice across 

 the polar region. Here is a piece of wood (specimen 

 exhibited) from the banks of a Siberian river carried 

 down in a floe of ice. That ice-floe with the wood 

 was found in latitude 76 30' N., and longitude 40 

 W. The pine-tree structure of the wood implies 

 that it grew in a country far north. It came, as I 

 said, embedded in an iceberg, and there is no possi- 

 bility of that except by its being carried, by one of 

 the great Siberian rivers which flow into the Arctic 

 Ocean from the land of Siberia, acoss the North 

 Pole into the latitude where it was found. There 

 may be islands round the North Pole, but we know 

 nothing of such. The Arctic Ocean, so far as 

 known, has no very great island in the middle of 

 it. This (second specimen shown) is a piece of 

 VOL. II. Z 



