GLACIER BAY. 723 



possible to decide, on such short observation, 

 whether these effects were due to local glacial 

 action, or whether they belonged to an earlier 

 general ice-period. But Agassiz became satis- 

 fied, as he advanced, that the two sets of phe- 

 nomena existed together, as in the northern 

 hemisphere. The general aspect of the op- 

 posite walls of the Strait confirmed him in 

 the idea that the sheet of ice in its former ex* 

 tension had advanced from south to north, 

 grinding its way against and over the southern 

 wall to the plains beyond. In short, he was 

 convinced that, as a sheet of ice has covered 

 the northern portion of the globe, so a sheet 

 of ice has covered also the southern portion, 

 advancing, in both instances, far toward the 

 equatorial regions. His observations in Eu- 

 rope, in North America, and in Brazil seemed 

 here to have their closing chapter. 



With these facts in his mind, he did not 

 fail to pause before Glacier Bay, noted for its 

 immense glacier, which seems, as seen from 

 the main channel, to plunge sheer down into 

 the waters of the bay. A boat party was 

 soon formed to accompany him to the glacier. 

 It proved less easy of access than it looked at 

 a distance. A broad belt of wood, growing, 

 as Agassiz afterward found, on an accumula- 



