100 ISLAND LIFE 



great features of land and sea as they now exist ; and we 

 shall see how utterly gratuitous, and how entirely opposed 

 to all the evidence at our command, are the hypothetical 

 continents bridging over the deep oceans, by the help 

 of which it is so often attempted to cut the Gordian 

 knot presented by some anomalous fact in geographical 

 distribution. 



Oceanic Islands as Indications of the Permanence of Con- 

 tinents and Oceans. — Coming to the question from the other 

 side, Mr, Darwin has adduced an argument of considerable 

 weight in favour of the permanence of the gi'eat oceans. 

 He says {Origin of Species, 6th Ed. p. 288) : " Looking to 

 existing oceans, which are thrice as extensive as the land, 

 we see them studded with many islands ; but hardly one 

 truly oceanic island (with the exception of New Zealand, 

 if this can be called a truly oceanic island) is as yet known 

 to afford even a fragment of any Palseozoic or Secondary 

 formation. Hence Ave may perhaps infer that during the 

 Palaeozoic and Secondary periods neither continents nor 

 continental islands existed where our oceans now extend ; 

 for had they existed, Palaeozoic and Secondary formations 

 would in all probability have been accumulated from sedi- 

 ment derived from their wear and tear ; and these would 

 have been at least j^artially upheaved by the oscillations of 

 level, which must have intervened during these enormously 

 long periods. If then we may infer anything from these 

 facts, we may infer that, where our oceans now extend, 

 oceans have extended from the remotest period of which 

 we have any record ; and, on the other hand, that where 

 continents now exist, large tracts of land have existed, 

 subjected no doubt to great oscillations of level, since the 

 Cambrian period." This argument standing by itself has 

 not received the attention it deserves, but coming in sup- 

 port of the long series of facts of an altogether distinct 

 nature, going to show the permanence of continents, the 

 cumulative effect of the whole must, I think, be admitted 

 to be irresistible.^ 



^ Of late it has been the custom to quote the so-called "ridge" down 

 the centre of the Atlantic as indicating an extensive ancient land. Even 

 Professor Judd at one time adopted this view, speaking of the great belt of 



