The summer ice hummocking takes on especially significant dimensions with the pressure of 

 ice under the influence of the wind and of the currents on the shores. If the shore is deep, the 

 pressure manifests itself in the formation of the littoral hummocks; if the shore is shallow, sum- 

 mer stamukhi are formed with the pressure of the ice on the littoral shallows and banks, stamukhi 

 which are grandiose in dimensions and consist of monoliths of ice 1 m or more thick, but less solid 

 or durable than autumn formations. 



At the very shore, the pressure of large masses of ice causes the advance of huge monoliths 

 further beyond the shore line, where they remain a long time until the surf and the sun finally 

 destroy them. 



Simultaneously, the pressure on the shallow shores with the movement of ice along the bot- 

 tom and the shore follows them as it would seem, and causes formation of a dam, which reminds 

 one of a moraine and which consists of unsorted littoral and shore material in contrast to the 

 sorted shore bank formed by the breakers.* 



Figure 94. Ice boulders on the shore. 



The blocks of floating ice at the shore often fall into the belt of the surf and here some are 

 rolled and rounded and thrown on the shore, and some, striking the bottom disintegrate into large 

 numbers of fine fragments. These fragments being rolled around quickly, take on the appearance 

 of boulders with dimensions of from a few centimeters to a meter or more (figure 94). Actual 



♦Besides the blocks of ice tossed onto the shore during ice hummocking, these blocks at the 

 very shore block up or fill up the sea to fill up its very bottom, forming the so-called "stone. " On 

 the White Sea, stones reach a thickness of 10 m. 



266 



