CHAPTER VII 



LAKES AND LAKE ICE OF CAPE ROYDS 

 AND CAPE BARNE 



Lakes and Lake Lee. The lakes which occupy the Ice-gouged depressions of the 

 peninsula of Cape Eoyds are of special interest. Owing to their accessibility during 

 the winter these lakes were examined in detail, and one or more trenches sunk In all 

 the more important ones. 



There are several lakes deserving of a separate individual description, but the 

 majority are small tarns, in winter occupied by a sheet of ice generally less than 

 3 feet thick. The ice in these tarns, unlike that in some of the larger lakes, was 

 found to melt entirely in the summer. 



In all the large lakes, and in some of the smaller, there flourishes a brovsm to reddish- 

 brown algous plant, which in some cases grows to such an extent that the accumula- 

 tion of vegetable matter resulting from its decay forms a layer of peat of appreciable 

 thickness on the lake bed. It seems probable that many of the smaller lakes 

 which contain little or none of this alga are not permanent, that is they may be 

 entirely removed during the winter and spring by ablation, or in the summer by 

 thawing. This was proved, in the case of some of the extremely small lakes, by our 

 observation that small depressions — coloured green by an algous growth — had already 

 by late November taken the place of the smallest of the tarns. Many of these, how- 

 ever, were refilled from time to time from the thaw-water of snow-drifts on the slopes 

 above them, and it was only at times of prolonged drought, when there was no snow 

 falling or drifting, that the depressions became quite dry. It is probable that these 

 lakes are in the majority of cases sub-permanent, since the thaw-water from the 

 drifts of late summer, when the sun does not rise high above the horizon, and thus 

 does not exert much heating influence on the rock-basins, would become frozen, and 

 would remain so until the tarns were entirely removed by evaporation, or until the 

 next summer thaw set in. There is no doubt of the permanency of the larger lakes, 

 although there are evidences showing a considerable restriction in size in some cases. 

 These evidences will, however, be dealt with when considering the lakes individually. 



The ice and water of most of the lakes is more or less salt, though there are 

 apparently one or two important exceptions, and this saltness is due probably to 

 a combination of two causes: (1) Wind action — decidedly the most important; 

 (2) filching of salts from the kenyte. 



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