It must also be remembered that the waters of both the North and South Pacific are peculiarly favourable to the navigation of small craft, and that Captain Bligh, after the mutiny on board the Bounty, was able to safely perform a journey of two thousand miles in an open boat; while all the islands both in North and South Polynesia must necessarily have been gradually peopled by the drifting over the ocean of stray canoes.
Again, as the tradition of the existence of a large continent west of the African coast was extant amongst the Egyptian priests long before the days of Solon, and, as I shall show hereafter, among the Carthaginians and Tyrrhenians, it is, I think, more than probable that both Phœnician and Egyptian mariners, either acting under a Royal Commission, or influenced by mercantile considerations, would endeavour to discover it, and, as in the case of Columbus, would have no difficulty in stretching across the Atlantic before a fair trade wind, though they might be less successful than him on their return.
The possibility of the existence of a large island or continent, midway between the Old and New World, within the traditional period, is included in the important question, which is still sub judice amongst geologists, whether the general disposition of land and water has or has not been variable during past ages. Sir Charles Lyell held the first view, and was of opinion[127] that complete alternations of the positions of continent and ocean had repeatedly occurred in geological time.
The opposite idea has been suggested at various dates by eminent authorities, suggested rather than sustained by elaborate arguments, until recently, when the question has been re-examined by Mr. Wallace and Dr. Carpenter.
The former, in that chapter of island life devoted to the permanence of continents, dwells forcibly upon Dr. Darwin’s inference from the paucity of oceanic islands affording fragments of either Palæozoic or Secondary formations “that perhaps during the Palæozoic and Secondary periods neither continents nor continental islands existed where our oceans now extend; for, had they existed, Palæozoic and Secondary formations would in all probability have been accumulated from sediment derived from their wear and tear; and these would have been at least partially 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.”
I am not aware whether Dr. Darwin has expressed himself more authoritatively on this point in later works, or whether the whole question has been discussed in detail otherwise than by Mr. Wallace in the chapter referred to, in which he quotes what must, I think, after all, only be taken in the light of a suggestion as an auxiliary to the powerful arguments which he himself has enunciated in favour of a similar conclusion. There is no doubt that the paucity of any but volcanic or coralline islands throughout the greatest extent of existing oceans has a certain but not absolute significance, so far as recent geological epochs are concerned.
There is another line of reasoning, debated by Mr. Wallace, based on the formation of the Palæozoic and Secondary strata from the waste of broken continents and islands occupying generally the site of the existing continents, and separated by insignificant distances of inland sea or extensions from the adjacent oceans. It is soundly based on their lithological structure, as generally indicative of a littoral and shallow water origin, but it seems to me to be only positive so far as it shows that, throughout geological time, some land has existed somewhere within the limits of the present upheaval, and simply negative as to what may or may not have been the condition of what are now the great ocean spaces of the world. Indeed, it would at first sight seem only reasonable to infer, that the very depressions which caused the inundations of Europe and Asia, during the deposition of any important formation, would imply a corresponding elevation elsewhere, in order that the same relative areas of land and water might be maintained.
This view has, however, been reduced in its proportions by Dr. Carpenter, who has levelled the results of the recent researches by the Challenger expedition against the advocates of the intermutations of land and ocean, and, in pursuing another line of reasoning from Mr. Wallace, has estimated the solid contents of ocean and land above the sea-level respectively, as bearing the proportion of thirty-six to one. So that, supposing all the existing land of the globe to sink down to the sea-level, this subsidence would be balanced by the elevation of only one thirty-sixth part of the existing ocean floor from its present depth to the same level.
It must be admitted that the balance of argument was until lately considerably against the former existence of the country of Atlantis, whose ghostly outlines, however, we could almost imagine to be sketched out by faint contours in the chart illustrative of the North Atlantic portion of the Challenger investigations. But it was not so overwhelming as to entitle us to ignore the story entirely as a fable. I do not conceive it impossible that some centrally situated and perhaps volcanic island may once have existed, sufficiently important to have served as the basis of simple legends, which, under the enchantment of distance and time became metamorphosed and enriched.
Mr. A. R. Grote suggests that it is simply a myth founded on the observation of low-lying clouds in a sun-flushed sky, which gave the appearance like islands on a golden sea.