A PECULIAR FORMATION OF SHORE ICE 



E. C. CASE 

 State Normal School, Milwaukee, Wis. 



On January 27 of the current year the writer noticed that the 

 ice along the Milwaukee shore of Lake Michigan from Lake Park 

 to the city pumping-station, a distance of nearly a mile, was 

 formed almost entirely of large snowballs such as are formed by 

 children rolling the damp snow until it grows into a ball by accretion. 

 The phenomenon was so peculiar that it led to a more careful 

 study, and as the author has found no report of a similar condition, 

 it seems worth while reporting. 



The beach where the peculiar formation occurred is not wide, 

 varying from only 3 or 4 feet to as much as 50 or 60 ; on the land- 

 ward side it terminates at the bottom of an 80-foot bluff of glacial 

 material, composed of the unstratified bowlder clay at the bottom 

 and stratified sands and clays above, culminating in the "red lake 

 clay" characteristic of the Wisconsin shore of Lake Michigan. 

 Beyond the edge of the beach the water is very shallow for a con- 

 siderable distance out, so that in time of even moderate waves bowl- 

 ders of 3 and 4 feet in diameter appear in the trough of the waves 

 100 and more feet from shore. This bench has been formed by 

 the waves cutting into the cliff and distributing the material on the 

 adjacent bottom. During ordinary winters this shallow water 

 freezes to the bottom very early, so that the ice-foot is far out beyond 

 the usual water-line. The exceptionally mild winter of 1905-6 did 

 not permit the water to freeze far out, so that at the end of January 

 there was only a very narrow zone of shore ice, extending out not 

 over 50-100 feet. 



At the time of the author's visit the condition was somewhat 

 as follows: There had been several very mild days with decided 

 thawing, and the beach presented the appearance of a compact 

 mass of balls of semi-solid ice, which upon investigation turned 

 out to be masses of snow crystals which, by thawing and freezing 



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