46 THE BERMUDA ISLANDS. 



As the result of our researches we may express the follow- 

 ing conclusions : 



1. The present form of the Bermuda Islands bears no relation 

 to the ring of an atoll, except in s© far as the outer boundary 

 may be more or less coincident with the boundaries of an 

 ancient atoll. 



2. The existence of an atoll in the present position of the Ber- 

 mudas is not demonstrable. 



3. The height of land in the archipelago was formed during 

 a period of elevation, when seemingly the entire archipelago 

 was a connected or continuous piece of land, extending as an 

 oval island to what is now the bounding reef on the north 

 and on the south. It is impossible to determine the absolute 

 amount of elevation above the water, but it appears to have 

 been not less than 70 or 80 feet, and it may have been con- 

 siderably more. 



4. The lagoons and sounds were formed duringaperiodof sub- 

 sidence which followed upon that of elevation, and is seemingly 

 still in progress, or was so until a comparatively recent period. 

 The great degradation of the coast-lime took place at this time. 

 It is impossible to determine the amount of such subsidence, 

 but it was at least 60-70 feet, and not improbably very much 

 more. 



It will be seen that these results, so far as they go, are in ab- 

 solute harmony with the views which Mr. Darwin entertained 

 regarding the structure of these islands. They do not prove 

 the correctness of the Darwinian hypothesis of the formation 

 of coral islands, but they measurably sustain it ; on the con- 

 trary, they are largely opposed to the requirements of the sub- 

 stitute theory' which has been recently proposed. Elevation 

 and subsidence are both shown to have marked the region in 

 its development, and these conditions are more in consonance 

 with the Darwinian hypothesis than with any other. 



