If the earth be a solid globe, I am at a loss to account for the principles on which earthquakes occur. Long before I heard of Symmes's theory, or perhaps before it had an existence in the mind of man, when reading accounts of earthquakes, it appeared to me altogether unaccountable, that such violent concussions could take place in one part of the world, and not be felt throughout the globe. It appears altogether inconsistent, that one part of a solid piece of matter, would be shaken so violently, without affecting the whole mass. We are informed by authentic history, that whole islands, and vast sections of country, have been sunk by earthquakes, and never more heard of. On the other hand, islands which are now inhabited, and productive, have been raised, apparently, from the bottom of the unfathomable ocean. How such things occur, I am unable to divine. If the globe be solid, on what principle could a large portion of its surface, which is said to be lighter than the parts beneath, sink into a dense medium? How could a heavy mass, lying a thousand fathoms deep at the bottom of the ocean, rise, and be suddenly elevated above the surface of the water, when all below is so compact, and governed by an opposite and immutable tendency? It appears to be a solecism in nature. The writer had once an opportunity of witnessing some of the effects of earthquakes. It was his fortune to be on the Mississippi river in the year 1812, at the time when that country was so violently convulsed with an earthquake. He saw and heard innumerable explosions, as though a large quantity of air had been confined in the bowels of the earth, and, seeking vent, rushed out with a tremendous sound; forcing up considerable quantities of sand through the apertures, in many instances mixed with black muddy water, and a substance resembling stone coal, or carbonated wood, which emitted a strong bituminous odour, when exposed to fire. At one place the river was stopped in its course a short time: the water rose to a considerable height above its common level; and, on the west side of the channel of the river, there was a counter-current for a few minutes of an astonishing velocity. So great was its force, that for some distance the cotton wood and willows on the margin of the river, were either prostrated or bent up the stream; and their branches looked as if they had been dragged a long way on the ground. The waters of the river soon subsided, and flowed in their natural direction.