234 GROVE KARL GILBERT— DAVIS 



kind of stream, changes in the direction of flow are caused by irregularities of the channel, and complex series of 

 phenomena arise from the resistance of the current to deflection. These series are strikingly parallel, but the 

 resistance to deflection is occasioned in one case by momentum and in the other by viscosity. 



After the return of the expedition, Gilbert spent the months of August and September, 

 1899, in the States of Washington and Oregon on local problems, and returned via California to 

 the city of Washington on October 10. He gave much time during two years folio-wing to the 

 report above outlined. The journey afforded him material for a number of communications to 

 scientific societies: Alaskan glaciers were described to the National Geographic Society on 

 December 1, and to the Washington Academy of Sciences on December 29, 1899. The mor- 

 phology of southern Alaska was discussed before the Geological Society of Washington on Janu- 

 ary 27, and the statics of a tidal glacier on March 25; Alaskan scenery was the subject of an ad- 

 dress to the American Institute of Mining Engineers on February 20; the relation of glacier 

 flotation and fiords was explained to the Philosophical Society of Washington on March 29, 1900. 

 The preparation of the volume on "Glaciers and glaciation" was not completed until the summer 

 of 1902. It is fitting that, as this fine volume did so much to make known the striking features 

 of Alaskan mountains, one of them which rises from Harriman Fiord to a height of over 10,000 

 feet should be given Gilbert's name, not merely in memory of his visit there but also in com- 

 memoration of his great contributions to American science. 



