286 R. S. TARR RECENT ADVANCE OF GLACIERS IN ALASKA 



writer, the phenomenon is unique; and yet, if the cause assigned is the 

 correct one, it is one which may well be expected in those mountain 

 glacier regions that are subject to violent earthquakes. In fact, if a great 

 shaking will cause a profound forward movement, it is probable that a 

 lesser shaking will cause a smaller advance. It is possible that some of 

 the observed changes in the fronts of glaciers are attributable to former 

 eartliquakes instead of climatic changes. 



The beginning of the advance in this case has been witnessed, and there 

 is every reason for believing that it will be continued, and that in the next 

 few years other glaciers will be affected. The uniqueness and importance 

 of the phenomenon makes it highly important that its progress and 

 effects should be carefully studied. It will be a great pity if some means 

 is not found by which the glaciers of this region can be carefully watched 

 for the next few years. 



