Icebergs do not frequently turn completely over. They will tip 90 

 degrees one day, then perhaps swing 80 degrees in another direc- 

 tion the next, but will seldom turn turtle. Irregular icebergs (valley 

 icebergs excepted) in general are the least stable. Occasionally an 

 iceberg will be observed with a regular oscillating movement, having 

 a period measured in minutes. 



Bergy bits, growlers, and floebergs are fragments of massive ice 

 afloat as contrasted with the more laminar form of undisturbed sea ice. 

 Bergy bits and growlers are more frequently the remnants or frag- 

 ments of icebergs. They also may be products of well-hummocked sea 

 ice, as are floebergs which are floes in origin but resemble small 

 icebergs in appearance. (Frontispiece, Figs. 86-98.) 

 ICEBLINK: (V.B.) — A yellowish-white glare on the underside of exten- 

 sive cloud areas created by light reflected from ice-covered surfaces. See 

 blink and sky map. (Fig. 15.) 



ICE BOULDERS, ICE BOWLDERS: 



(1) (I.B.l.b.) — Large fragments of sea ice that have been shaped by 

 erosion into the form of boulders or nearly spherical ice pieces and 

 then forced ashore. See shore ice. (Fig. 56.) 



(2) (V.C.) — Boulders (rock) transported and deposited through glacial 

 action. Cf. erratic. 



ICEBOUND: (V.A.) — Surrounded by ice so as to be incapable of ad- 

 vancing, as an icebound vessel. Cf. beset, nipped. 

 ICE BRIDGE: (IV.) — The freezing over of a river which impedes or 



prevents navigation by ordinary ships. 

 ICE CAKE: (I.A.2.) — A general term, like floe, used in reference to 



flat fragments of ice. The dimensions of a cake are not fixed and the 



term is used when no specific size is intended. Cf . floe. 

 ICE CAP: (II.A.l.a.) — Continental ice. 

 ICE CASCADE: (II.B.) — Ice fall. 

 ICE CAST: (I.B.l.a.) — Ice formed as a shell around pebbles on a beach 



as a result of wetting by spray, tide, and waves. Sometimes ice casts 



become detached from the parent pebbles and coalesce to serve as a 



nucleus for a wash and strain ice footc 

 ICE CHART: (V.A.) — A chart showing the prevalence of ice, usually 



with reference to navigable waterways. Cf . ice atlas. 

 ICE CLIFF: (H.A.) — The clifF-like front of a glacier, or of shelf ice 



where it meets the sea (Figs. 78, 80-84) . 

 ICE CRUST: (I.A.3.b.) — Thin, hard sea ice. Ice crust has varying 



degrees of whiteness depending upon age, thickness, and/or the rapidity 



of formation. Cf . winter ice. 

 ICE CRYSTAL: (I., II., III., IV., and V.B.)— The form in which ice 



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