b = the decrease in the length of the field as the result of the hummocking, it is obvious that 



L — l = b. (1) 



^- 



I 



wmm i 



-'W^' 



VJ 

 <<'' 



Figure 103. The increase in the area of the field with hummocking. 

 But since the decrease of the ice field leads completely to the formation of hummocks, then 



bH = kaih + z), (2) 



where H = the thickness of the ice field, 



h = the average height of the above ice part of the hummock, 



3 = the average emersion of the under water ice part of the hummock, 



k = the coefficient of filling of the hummocks; this coefficient under the condition of iso- 

 static balance is equal to the above- and under- ice parts of the hummocks. 



Substituting formula (1) in (2) we get 



L — / = 



kaih + z) 



but 



H 



a__N_ 

 i ~10' 



(3) 



(4) 



where N = the point of hummocking of the field. 



Substituting formula (4) in (3), we get 



/ 



' ■+*^('+i) 



10 



(5) 



If we substitute 



then we get, 



fc=0.3, -|=3, ^ = 6, 



1 



1 + 0.6A^ 



(6) 



286 



