The daily morning journal and courier. [volume] (New Haven, Conn.) 1894-1907, 1898-06-07


and feet. Such slightly submerged
plains of great breadth occur on the
banks between Honduras and Jamaica.
The Windward Islands are fragments
of a plateau, which an emergence of
less than three thousand feet would
unite into one body of land. Both to
the east and west of Jamaica there are
pleateaus depressed to between three
thousand feet and four thousand feet
Still lower plateaus are indicated in the
Caribbean Sea, which reaches to
depth of fifteen thousand feet.
From the existence of these submerg-
ed plateaus it becomes apparent that
change Of elevation of from two thous-
and feet to four thousand feet would
not merely unite Cuba and Florida, but
would greatly enlarge the West Indian
lands, and almost connect North Amer
lea and South America. Such a change
of elevation would nearly barricade the
Antillean water into three basins-the
Caribbean Sea, the Sea Of Honduras
and the Gulf of Mexico. The Sea of
Honduras, between Cuba and Jamaica,
reaches to the phenomenal depth of
twenty thousand feet, in the form of
long, narrow channel. The structure
of these sea basins at various depths
has been mapped by many writer's, but
the character of the channels which
dissect the drowned plateaus had been
almost entirely passed over until the
appearance Of the writer's previous
papers.
From the apparently complete ana
logy between the characteristics Of the
land and submarine valleys or channels
namely, ID the submarine valleys be-
ing combinations of those of the con-
tinent or island; (2) both having tribu
taries converging from every possible
direction; 90 both classes of valleys
having their magnitude of correspond
ing proportions, with (3) similar great
canons and amphitheatrelike tribu-
taries; (5) both terrestrial and sub
marine channels with similar graduation
plains and steps characterizing their
slopes; co. without obstructing barriers
the conclusion Is reached that the
depths of the submarine channels may
be used as yardstlcks to show that the
land lately stood nearly as high as the
valleys are deep.
Applied to the West Indian region
and ajacent parts of the continent, it
would thus appear that these regions
stood from ten thousand to twelve
thousand feet, or in some localities
fourteen thousand feet, higher than
now. The West Indian bridge reached
a height of from two to more than two
and half miles, while the floors of the
Gulf of Mexico and the Caribbean Sea-
~ h t11> ~ = J1g,xye
can be traced, were continental plains,
like those of the Mississippi or Amazon
of the present day, with perhaps some
shallow lakes or small seas. The back
bone of this West Indian bridge was
near the Atlantic side, and remains of
it are seen in the ridge dissected during
the epoch of high elevation by the rap
idly descending streams which now
constitute the chain of the Windward
| Islands.
The plains now forming the floors Of
| the Gulf of Mexico and the Honduras
and Caribbean seas were apparently
drained into the Paclfis ocean across
the Tehuantepec Isthmus, Honduras,
| Nicaragua, Panama and other low de-
pressons farther south. The writer's
recent explorations in the Tehuantepec
Isthmus confirm this hypothesis.
| Plateaus Of Mexico and Central Amer
| lea, rising from six thousand to ten
| thousand feet, are there reduced in
| height for distance Of more than
sixty miles, so that we find half uasses
as low as eight hundred feet above the
sea. During the earlier period of the
elevation of the Antillean region the
| Tehuantepec Isthmus was a strait in
which a deep-water fauna was living.
Later the strait was transformed into
| land troughs, fragments of the old
base-level floor of which are still ex-
tant and through them narrow geolog-
| ical canals We're formed when the low
Mexican plains had again sunk be-
meath the Gulf waters. This question
of the elevation of the Mexican and
| Central American barriers would carry
US beyond the limits of the present pa
per- SO that all that can now be said of
| them is that they were elevated at a
very date, corresponding to the sub
sidence of the West Indian region, to
heights reaching from six thousand to
even more than ten thousand feet. This
elevation was a sort of compensation In
the terrestrial balance.-Dr. j. w.
Spencer, in The Popular Science
Monthly.