must have been
carried up from a considerable depth by the force of the same gases
which make the little mud-volcanoes.

Now and then this 'Salse,' so quiet when we saw it, is said to be
seized with a violent paroxysm. Explosions are heard, and large
discharges of mud, and even flame, are said to appear. Some
seventeen years ago (according to Messrs. Wall and Sawkins) such an
explosion was heard six miles off; and next morning the surface was
found quite altered, and trees had disappeared, or been thrown down.
But--as they wisely say--the reports of the inhabitants must be
received with extreme caution. In the autumn of last year, some
such explosion is said to have taken place at the Cedros Salse, a
place so remote, unfortunately, that I could not visit it. The
Negroes and Coolies, the story goes, came running to the overseer at
the noise, assuring him that something terrible had happened; and
when he, in defiance of their fears, went off to the Salse, he found
that many tons of mud--I was told thousands--had been thrown out.
How true this may be, I cannot say. But Messrs. Wall and Sawkins
saw with their own eyes, in 1856, about two miles from this Cedros
Salse, the results of an explosion which had happened only two
months before, and of which they give a drawing. A surface two
hundred feet round had been upheaved fifteen feet, throwing the
trees in every direction; and the sham earthquake had shaken the
ground for two hundred or three hundred yards round, till the
natives fancied that their huts were going to fall.

There is a third Salse near Poole River, on the Upper Ortoire, which
is extinct, or at least quiescent; but this, also, I could not
visit. It is about seventeen miles from the sea, and about two
hundred feet above it. As for the causes of these Salses, I fear
the reader must be content, for the present, with a somewhat muddy
explanation of the muddy mystery. Messrs. Wall and Sawkins are
inclined to connect it with asphalt springs and pitch lakes. 'There
is,' they say, 'easy gradation from the smaller Salses to the
ordinary naphtha or petroleum springs.' It is certain that in the
production of asphalt, carbonic acid, carburetted hydrogen, and
water are given off. 'May not,' they ask, 'these orifices be the
vents by which such gases escape? And in forcing their way to the
surface, is it not natural that the liquid asphalt and slimy water
should be drawn