SAND DUNES 



Another interesting phenomenon of arctic 

 weather is the geyser-like bubbling occasion- 

 ally seen along the beach at high tide in two 

 or three feet of water. For minutes at a time 

 geysers a foot in diameter belch forth great 

 streams of air which throw the water up in 

 miniature fountains. The explanation of this 

 seems rather obscure, but I have thought that 

 a sudden severe frost at the time of the ebb 

 had sealed the surface of the sand, and the 

 water, escaping beneath, had left numerous 

 interstices into w^hich the air permeated, to 

 escape when the warm water of the rising tide 

 melted the ice seal and forced out the air. 

 Possibly the presence of dead thatch grass, 

 thrown up and buried in the sand, aided in 

 the accumulation of air. This phenomenon is 

 very different from the tiny air spouts that 

 arise from the burrows of beach fleas. 



As one walks along the edge of the dunes 

 near the beach in summer or winter, his at- 

 tention may be attracted by a number of balls 

 which appear to be made up of broken pieces 

 of straw or grass. Some of these are not 

 larger than a tennis ball, others the size of 

 a cocoanut; some are perfectly spherical and 

 firmly matted, others are loosely formed and 



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