INTRODUCTION 



away, the rookery is seen to be composed of a 

 series of undulations and mounds, or "knolls," 

 while several sheets of ice, varying in size up to some 

 hundreds of yards in length and one hundred yards 

 in width, cover lower lying ground where lakes 

 of thaw water form in the summer. Though 

 doubtless the ridges and knolls of the rookery 

 owe their origin mainly to geological phenomena, 

 their contour has been much added to as, year 

 by year, the penguins have chosen the higher 

 eminences for their nests ; because their guano, 

 which thickly covers the higher ground, has 

 protected this from weathering and the denuding 

 effect of the hurricanes which pass over it at 

 certain seasons and tend to carry away the small 

 fragments of ground that have been split up by the 

 frost. 



The shores of this beach are protected by a 

 barrier of ice-floes which are stranded there by the 

 sea in the autumn. These floes become welded 

 together and form the "ice-foot" frequently re- 

 ferred to in these pages, and photographs showing 

 how this is done are seen on Figs. 5, 6, 7 and 8. 



At the back of the rookery, nesting sites are 

 to be seen stretching up the steep cliff" to a height 

 of over 1000 feet, some of them being almost 

 10 



