Nearly the whole of Hayti lies between the eighteenth and twentieth degrees of latitude, and the sixty-ninth, and seventy-fifth of longitude.  Its greatest length is three hundred and forty miles, its greatest breadth, one hundred and thirty-two.  It has a surface of somewhat more than twenty-seven thousand square miles, or about eighteen million square acres.  The greater part of this is mountain-land.  There are three extensive plains,—­La Vega in the east, Santiago in the north, and Les Plaines in the southeast.  These are distinct from the Savannas.[A] The island is about the size of the State of Maine.  Its shape is peculiar, as it widens gradually from its southeastern end to nearly the centre of its greatest length, whence the southern coast trends rapidly to the north and west and stretches into a peninsula, like a long mandible, corresponding to which on the northern coast is another half as long, like a broken one, and between these lies a great bay with the uncultivated island of Gonaive.  The eastern part of the island has also the small peninsula of Saniana, lying along the bay of that name.  The surface is covered by mountains which appear at first to be tossed together wildly, without system or mutual relation, but they can be described, upon closer inspection, as four ranges, with a general parallelism, extending nearly east and west, but broken in the centre by the Cibao ridge, which radiates in every direction from two or three peaks, the highest in the island.  Their height is reputed to be nine thousand feet, but they have not yet been accurately measured.  The mountains of La Hotte, which form the long southern tongue of land, rise to the height of seven thousand feet.  They are all of calcareous formation, and abound in the caverns which are found in limestone regions.  Some of these have their openings on the coast, and are supposed to extend very far inland; they receive the tide, and reject it with a bellowing noise, as the pent air struggles with it under their arched roofs.  These were called by the Spaniards baxos roncadores, droning or snoring basses.  The French had a name, le gouffre, the gulf, to describe these noises; but they also applied it to the subterranean rumbling, accompanied with explosions and violent vibrations of the ground, which is caused by the heavy rains soaking through the porous stone, after the dry season has heated the whole surface of the island.  The steaming water makes the earth groan and shake as it forces its way through the crevices, feeling for an outlet, or thrown back upon its own increasing current.  These mysterious noises filled with awe the native priests who managed the superstition of the island before the Spaniards introduced another kind:  no doubt they served for omens, to incite or to deter, voices of Chthonian deities, which needed interpreting in the interest of some great cacique who would not budge upon his business without the sanction of religion.  Many a buccaneer, in after-times, who quailed before no mortal thunders made by French or Spanish navies, was soundly frightened by the gigantic snoring beneath his feet into reviewing his career, and calculating the thickness of the crust between himself and his impatient retribution.