The Malaspina Glacier. 187 



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summer days, but the water finds its way down into the glacier 

 and joins the general subglacial drainage. It is evident that the 

 streams beneath the surface must be of large size, as they furnish 

 the only means of escape for the waters flowing beneath the 

 Agassiz, Seward and Marvine glaciers, as well as for the waters 

 formed by the melting of the great Malaspina glacier. 



The outer borders of the Malaspina glacier are practically 

 stationary, but there are currents in its central part. Like the 

 expanded ends of some of the Alpine glaciers, as the Galiano 

 and Lucia glaciers, for example, this glacier is of the nature of a 

 delta of ice, analogous in many of its features to river deltas. 

 As a stream in meandering over its delta builds up one portion 

 after another, so the currents in an expanded ice-foot may now 

 follow one direction and deposit loads of debris, and then 

 slowly change so as to occupy other positions. This action 

 tends to destroy the individuality of morainal belts and to form 

 general sheets of debris. The presence of such currents as here 

 suggested has not been proved by measurements, but the great 

 swirls in the Malasj^ina glacier and the tongues of clear ice in 

 the upper portions of the debris fields on the smaller glaciers 

 strongly suggest their existence. 



The Malaspina glacier is evidently not eroding its bed ; any 

 records that it is inaking must be by deposition. Should the 

 glacier melt away completely, it is evident that a surface formed 

 of glacial debris, and very similar to that now existing in the 

 forested plateau east of Yakutat bay, would be revealed. 



The former extent of the Malaspina glacier cannot be deter- 

 mined, but it is probable that during its greatest expansion it 

 extended seaward until deep water was reached, and broke ofl" 

 in bergs in the same manner as do the Greenland glaciers at the 

 present day. Soundings in the adjacent waters might possibly 

 determine approximately the former position of the ice-front, 

 and it is possible that submarine moraines might be discovered 

 in this way. The Pimpluna reefs, reported by Russian navi- 

 gators and indicated on many maps, may possibly be a remnant 

 of the inoraine left by the Piedmont glacier from the adjacent 

 coast. 



The glaciers west of Icy bay were seen from the top of Pin- 

 nacle pass cliffs, and are evidently of the same character as the 

 Malaspina glacier and fully as extensive. A study of these Pied- 



