Smithsonian Report. IPSO. -Blark 



PLATE 5 



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1. Thill section of ground it-e from an ice wedge near Barrow, Alaska, showing 

 numerous air bubbles. Photographed January 23, 1950. 



2. Thin section of ground ice from an ice wedge near Barrow, Alaska, showing 

 silt and individual ice crystals bv using transmitted light and crossed polar- 

 oids. Photographed April 21, 1950. 



