168 WAVES OF SAND AND SNOW 



houses, thd cloud of extremely fine particles 

 stretching to leeward beyond the tail of the horse- 

 shoe bank. 



In December the snow in the woods near Mon- 

 treal was neither the fine dust nor the sand-like 

 grains seen on the Manitoba prairies in January 

 and February, but seemed to consist of the original 

 flat crystals in which snow falls when the air is 

 moderately dry and cold, but more or less broken 



Fig. 22 

 Plan of hollow round atree^wind from the left . 



up. The trees stood in many cases fairly far apart 

 with little or no undergrowth, and the wind swept 

 through the wood. The snow remained quite loose 

 and light, and had no crust upon the surface. 

 It embraced the saplings closely, but a space of 

 peculiar shape remained unfilled round each larger 

 tree, for the larger tree causes eddying motion of 

 such intensity as to toss away the snow (Figs. 22, 

 23, 24). Round the trunk from either hand the 

 wind sweeps in a spiral, or corkscrew, fashion, 



