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Sierra Club Bulletin. 



water near the shore there are no boulders, or if any are 

 seen they are of large and exceptional size. Should one 

 reason from these facts that the boulders of the rampart 

 came from the land, or that they came from the water? 

 An argument might be made in favor of either side, but 

 only one of the arguments would find favor with the 

 geologist, because he has a theory to account for the 

 general distribution of boulders throughout the region 

 of abundant lakes. He has learned that they were trans- 

 ported by glaciers, and that except where they are massed 

 together in moraines the glaciers merely strewed them 

 over the surface. While the glaciers were doing their 

 work there was no distinction of lake and land, and the 

 lake basins received their quotas of boulders along with 

 the surrounding dry land. To the geologist, therefore, 

 the absence of the boulders from the shallows of the lake 

 is as remarkable a phenomenon as their abundance at the 

 shore ; and the two facts are fitted together accurately by 

 the theory that the boulders now at the shore were once 

 scattered over the lake bottom in shallow water, and have 

 by some agency been moved toward the shore and massed 

 together there. 



By what agency were the boulders moved ? Were they 

 gathered from the water and heaped along the shore by 

 the aboriginal inhabitants of the country? That, so fc^r 

 as I know, was the first guess made; and the name 

 *'rampart" was given in allusion to the general resem- 

 blance which some of the boulder ridges bear to walls 

 built for purposes of fortification. The idea is not espe- 

 cially plausible, because the position of the ramparts does 

 not accord with any rational theory of attack and defense ; 

 but the broader idea that the work of assembling the 

 boulders was performed by men is not easily disproved. 

 The evident reasons against it are mostly negative: the 

 lack of a plausible motive, and the fact that we have no 

 definite knowledge of similar work having been done by 

 men. Nevertheless, the human theory has been prac- 

 tically abandoned ; for, though not disproved, it has been 



