334 SUTHERLAND'S SCIENTIFIC OBSERVATIONS. 



hours. The reader can form his own opinion as to the 

 identity of the pigeon in question. 



We have already alluded to Captain Penny's expedi- 

 tion, fitted out by Lady Franklin. His little vessels, 

 the Lady Franklin and the Sophia, entered Davis's Strait 

 on the 26th of April, 1850 ; but they did not get into 

 the open water at the head of Baffin's Bay until the 18th 

 of August. Nearly four months they were squeezed 

 about among the drifting ice in this tedious and terrible 

 passage, sometimes closely wedged on the shore-ice, 

 and sometimes tracking by manual labor through the 

 breaking pack. Some facts of a scientific interest are 

 mentioned by Dr. Sutherland, who accompanied Penny. 



The first great difficulty the Arctic voyager has to 

 contend with is the capricious state of the navigation 

 in the grand approach to the Polar Sea. The melting 

 of the ice and snow in the north of Baffin's Bay pro- 

 duces a continuous stream of water, which flows stead- 

 ily to the south. As soon as this current leaves the 

 projecting points at the head of the bay, a thin film of 

 ice is formed on it. This ice gets thicker and thicker 

 as it moves southwards, by congealing new layers of 

 sea-water on its under surface, and by storing up snow 

 and sleet above, until it becomes what the whaler calls 

 the middle-ice of the bay. In winter it extends from 

 shore to shore ; but in summer it is separated from the 

 Greenland coast by an open lane of water, in conse- 

 quence of its connection with the fringe of land, ice be- 

 ing dissolved where northerly winds prevail. An open 

 space of water is always left by this southward drift of 

 the ice-pack at the northern extremity of Baffin's Bay ; 

 the extent of the space varies, however, with the 

 season. In winter, it is diminished by the shooting out 

 of the land-ice towards the drift, and the quickened form- 

 ation of the yung ice ; in summer, it is increased by the 



