Earthquakes have been remarked by some to happen usually upon sudden changes of weather, and particularly after violent heats; but I do not vouch this upon my own experience, which has been pretty ample.  They are preceded by a low rumbling noise like distant thunder.  The domestic cattle and fowls are sensible of the preternatural motion, and seem much alarmed; the latter making the cry they are wont to do on the approach of birds of prey.  Houses situated on a low sandy soil are least affected, and those which stand on distinct hills suffer most from the shocks because the further removed from the centre of motion the greater the agitation; and the loose contexture of the one foundation, making less resistance than the solidity of the other, subjects the building to less violence.  Ships at anchor in the road, though several miles distant from the shore, are strongly sensible of the concussion.

New land formed.

Besides the new land formed by the convulsions above described, the sea by a gradual recess in some parts produces the same effect.  Many instances of this kind, of no considerable extent however have been observed within the memory of persons now living.  But it would seem to me that that large tract of land called Pulo Point, forming the bay of the name, near to Silebar, with much of the adjacent country has thus been left by the withdrawing or thrown up by the motion of the sea.  Perhaps the point may have been at first an island (from whence its appellation of Pulo) and the parts more inland gradually united to it.* Various circumstances tend to corroborate such an opinion, and to evince the probability that this was not an original portion of the main but new, half-formed land.  All the swamps and marshy grounds that lie within the beach, and near the extremity there are little else, are known, in consequence of repeated surveys, to be lower than the level of high-water; the bank of sand alone preventing an inundation.  The country is not only quite free from hills or inequalities of any kind, but has scarcely a visible slope.  Silebar River, which empties itself into Pulo Bay, is totally unlike those in other parts of the island.  The motion of its stream is hardly perceptible; it is never affected by floods; its course is marked out, not by banks covered with ancient and venerable woods but by rows of mangroves and other aquatics springing from the ooze, and perfectly regular.  Some miles from the mouth it opens into a beautiful and extensive lake, diversified with small islands, flat, and verdant with rushes only.  The point of Pulo is covered with the arau tree (casuarina) or bastard-pine, as some have called it, which never grows but in the seasand and rises fast.

(Footnote.  Since I formed this conjecture I have been told that such a tradition of no very ancient date prevails amongst the inhabitants.)

Encroachment of the sea.