22O 



PLATE CXI. MINNA BLUFF AND ITS NEIGHBOURHOOD. 



FIG. 1 (Map A). From photographs by E. H. SHACKLETON (Sh. 191 and 185, 

 ^-plates), Jan. 24, 1903 ; looking N. from the Barrier surface. 



FIG. 2 (Map B). From a photograph by E. H SHACKLKTON (Sh. 91, i-plate), 

 Feb. 21, 1902; taken off the coast of White Island. 



Minna Bluff is a long and narrow promontory which projects S.-E. from the 

 foot of Mount Discovery. Measuring 35 miles in length, it is rarely more than 

 5 miles across, and has a height of 2000 feet. It is volcanic in origin, and 

 from its position offers an obstruction to the movement northwards of tlie Barrier 

 ice. Round its end, and between it and White Island, is a good deal of disturbed 

 ice and morainic material. This, however, must not be taken to account for the 

 fractured ice-mounds shown in Fig. 2. 



Near the north end of White Island were a number of such mounds with star- 

 shaped fractures on the top. In connection witli them were collections of perfect 

 crystals of sodium sulphate (Glauber's salt), lying upon the ice. Similar masses of 

 this salt were found also in other spots, either upon glacier-ice or forming part of 

 old moraines. In this case the ice upon which they were found formed part of 

 the Great Ice Barrier, and they were caused probably by the freezing of salt- 

 saturated thaw-water which had collected beneath the ice from the neighbouring 

 slopes of White Island. 



See Ferrar, Nat. Hist. Rep., vol. i., pp. 11, 91. 



