Comparison with 1861 |
|
do not appear to have inhabited profound depths, in the several formations of Europe and of the United States; and from the amount of sediment, miles in thickness, of which the formations are composed, we may infer that from first to last large islands or tracts of land, whence the sediment was derived, occurred in the neighbourhood of the existing
continents of Europe and North America. ↑1 blocks not present in 1859 1860 1861 1866 1869; present in 1872 | This same view has since been maintained by Agassiz and others.
|
But we do not know what was the state of things in the intervals between the successive
formations; whether Europe and the United States during these intervals existed as dry land, or as a submarine surface near land, on which sediment was not deposited, or again
as the bed of an open and unfathomable sea. |
|
Looking to the existing oceans, which are thrice as extensive as the land, we see them studded with many islands; but not
one oceanic
island
is as yet known to afford even a remnant of any palæozoic or secondary formation. Hence we may perhaps infer, that during the palæozoic and secondary periods, neither continents nor continental islands existed where our oceans now extend; for had they existed
there,
palæozoic and secondary formations would in all probability have been accumulated from sediment derived from their wear and tear; and would
have been at least partially upheaved by the oscillations of level, which we may fairly conclude
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
earliest Silurian earliest Silurian 1861 1866 1869 | earliest silurian 1859 1860 | Cambrian 1872 |
period. The coloured
map appended to my volume on Coral Reefs, led me to conclude that the great oceans are still mainly areas of
|
do not appear to have inhabited profound depths, in the several formations of Europe and of the United States; and from the amount of sediment, miles in thickness, of which the formations are composed, we may infer that from first to last large islands or tracts of land, whence the sediment was derived, occurred in the neighbourhood of the
existing existing 1859 1860 1861 1866 | now existing 1869 1872 |
continents of Europe and North America. ↑1 blocks not present in 1859 1860 1861 1866 1869; present in 1872 | This same view has since been maintained by Agassiz and others.
|
But we do not know what was the state of things in the intervals between the
successive successive 1859 1860 1861 | several successive 1866 1869 1872 |
formations; whether Europe and the United States during these intervals existed as dry land, or as a submarine surface near land, on which sediment was not deposited, or
....... 1860 1861 1866 1869 1872 | again 1859 |
as the bed of an open and unfathomable sea. |
|
Looking to the existing oceans, which are thrice as extensive as the land, we see them studded with many islands; but
not not 1859 1860 1861 1866 1869 | hardly 1872 |
one
oceanic oceanic 1859 1860 1861 |
truly oceanic island (with the exception of New Zealand, if this can be called a truly oceanic 1866 1869 1872 |
island island 1859 1860 1861 | island) 1866 1869 1872 |
is as yet known to afford even a remnant of any palæozoic or secondary formation. Hence we may perhaps infer, that during the palæozoic and secondary periods, neither continents nor continental islands existed where our oceans now extend; for had they
existed existed 1859 1860 1861 1866 | existed, 1869 1872 |
there, there, 1859 1860 1861 1866 | there, 1869 1872 |
palæozoic and secondary formations would in all probability have been accumulated from sediment derived from their wear and tear; and
would would 1859 1860 1861 1866 | these would 1869 1872 |
have been at least partially upheaved by the oscillations of level, which
we may fairly conclude we may fairly conclude 1859 1860 1861 1866 |
OMIT 1869 1872 |
must have intervened during these enormously long periods. If then we may infer anything from these facts, we may infer
that that 1859 1860 1861 | that, 1866 1869 1872 |
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
earliest silurian earliest silurian 1859 1860 | earliest Silurian 1861 1866 1869 | Cambrian 1872 |
period. The
coloured coloured 1859 1860 1861 1866 1869 | colored 1872 |
map appended to my volume on Coral Reefs, led me to conclude that the great oceans are still mainly areas of
|