220 Canadian Record of Science. 



The process by which the final stage, if it may be so 

 called, is reached, is not only of great interest in itself, but 

 particularly so because it is now, as it has doubtless been 

 throughout the whole history of the islands, going on, and 

 can be studied in all stages of progress. 



The beginning of this process must be sought for in the 

 reefs which surround the islands, and protect them from 

 the direct force of the sea. Out on tlie reefs, where 

 the coral is living and growing, fragments are constantly 

 broken off and thrown in towards the shore by the vio- 

 lence of the surf, to be by the same means gradually 

 ground up into a fine sand, which is eventually washed up 

 to form a beach, wide stretches of which are exposed at 

 low water. 



From this point the evolution of the rock formation 

 may be said to begin. The sand is blown inland by the 

 wind, forming great ridges, which have the appearance of 

 enormous snowdrifts. The principal " sand-glacier " where 

 this is now to be seen is at Elbow Bay, on the south shore, 

 where the sand has drifted far inland to great depths, 

 completely filling up valleys, and even overwhelming 

 houses in its progress. The whole of the land has been 

 formed in the same manner, as in some of the quarries a 

 stratum of the red surface soil is sometimes seen under 30 

 or 40 feet of more recent rock, formed by the sand drifting 

 over the land surface, and then becoming consolidated. 



The first stage in the formation of the land is thus 

 reached, when the sand has been piled up into a hill, which 

 continues to grow until it has perhaps assumed a form, 

 which prevents it from continuing to drift in the same 

 direction. 



When ihis stage has been reached, the surface soon 

 becomes covered with vegetation, and the process towards 

 the next stage begins. The sand by its own weight 

 becomes more compact, especially where the drift is of 

 great depth, and through the action of the rain water per- 



