119 
Erect or Ick 1n Lakr Upon THE SuHore LINE. 
By Apert B. REAGAN. 
On coming to northern Minnesota last year, I visited several islands 
in Pelican Lake near Orr, in St. Louis County. The country in that region 
is very stony, mostly boulders of glacial origin. Around the borders of 
several of the islands, especially the low islands, there was a ridge of 
cobble stones and boulders, sometimes almost assuming the form of a stone 
fence. It struck my curiosity. It was spring, however, before I had solved 
the mystery. At the breaking up of the ice in the lake, a strong southwest 
wind drove the ice upon the islands on the wind-exposed sides to a height 
of over twelve feet in one case, a literal glacier being shoved inland. The 
ice being thus shoved forward and piled up on the land, shoved the loose 
rock of the shallow lake next the island inland so that the “moraine” thus 
formed was the stone wall I had noticed. It might also be added that 
some of the scratchings on shore rocks of lakes in this northern region 
may be due to the same local action. 
