C H A P T E R X X I I I
PHYSICAL CHARACTERISTICS OF PUERTO RICO
fH E great submarine plateau from which the
Bahama Islands spring and the vast ocean
ridges to the south of it converge to an apex some
1500 miles from their western origin. T he two
ridges which run through Cuba and Jamaica, one
having its apparent point of departure at Yucatan
and the other at the angle of Honduras, coalesce in
the island of Haiti, and sink again below the sea-
level in a single ridge, which reappears at a distance
of ninety miles in the island of Puerto Rico. This
island stands like a huge pillar, with deep abysses
on either side, between the broad and varied formation
which constitutes a submerged extension of the
continent and the long chain of rocky and coralline
isles that sweeps in a vast semicircle to the coast of
South America. It stands guard at the main entrance
to the Caribbean Sea from the Atlantic
Ocean, in the natural pathway from the east to the
narrow isthmus which divides the American Mediterranean
from the Pacific. T he channel between
Haiti and Puerto Rico is called the Mona Passage,
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