waters of the sea, which obviously must, at one time, have existed; and that almost all the active volcanoes now known are situated near the sea coast, and rarely, or never, far in the interior of large continents, we have very great reason to conclude, that the utmost depths of volcanic action are not much, if at all, greater than those we have found reason to assign to the ocean itself, that is, from one to five miles.

Catopaxi, in South America, is, perhaps, of all volcanic mountains, the most distant from the sea; and yet it is only 140 miles from the shores of the Pacific. This remarkable volcano, which is nearly 19,000 feet above the level of the sea, presents us with a very strong corroboration of what has been said, that water is the great agent in volcanic action; and that the deepest source of this activity is not greater than has been above supposed. This volcano, from time to time, throws up, not only great quantities of mud, but also innumerable fish. The almost extinct volcano of Imbarbara, has also frequently thrown up fish in such quantities, as to cause putrid exhalations over the whole neighbouring country. The species of fish thus thrown up, is that called by the natives of Quito, permadilla; it is about four inches in length, and is almost the only fish found in the lakes and waters of Quito: but the great num

bers occasionally thrown out, give us reason to suppose that there must be very considerable subterraneous lakes in the calcareous caverns of that country in which these fish are bred, and from which the volcanic action of these mountains so far from the sea, is supplied with the necessary quantity of water. In this case we are certain, that those lakes cannot be at any very great depth below the general surface of the country, as the fish could not exist, deprived of atmospheric air.

According to Humboldt, the volcanoes of America scarcely ever throw out lava; but chiefly slag, ashes, pumice, and vast quantities of water and slime. We consequently never hear of burnings in the tremendous eruptions of Quito, but only of overflowings of slimy mud. During the great earthquake of the 4th of February, 1797, 40,000 human beings were destroyed by the water and mud that issued from the mountains. In the description of the mud volcanoes in the island of Trinidad, given by Dr. Ferguson, in the Edinburgh Transactions, one of the party who was examining them picked up a white sea shell of the turbinated kind, in the act of being thrown out along with the mud; a very sufficient proof of a subterraneous communication with the sea.

It has been remarked, that no known volcano

is seated in granite, nor is it found near any volcano, except in very low situations. The same may be said of primitive rocks in general. The volcanic formation of Iceland is, probably, the most extensive in the world, covering a space of, at least, 60,000 square miles; yet there is no appearance of primitive rock in the whole of that island, though the mountains reach an elevation of nearly 6000 feet above the sea. One eruption of Ætna covered a space of fifty leagues in circumference, and one hundred and twenty feet in thickness, with calcareous sand or dust; and as calcareous earth enters very sparingly into the composition of what are considered primitive rocks, though it forms a large proportion of the secondary, we have thus another strong reason for supposing that volcanoes are not very deeply seated in the earth.

The whole volcanic formation of which Vesuvius forms the focus, reposes upon the secondary lime stone, of which the Appenine range is there formed. Of this we have various direct proofs, the most remarkable of which is the frequent projection of calcareous bodies from the crater, either in an unaltered, or in a modified state. When we connect this fact with the probable, and almost obvious communication with the waters of the neighbouring sea,

we cannot but consider it as highly probable that the focus of this volcano is at a depth below the surface of the land, not much, if at all, greater than the thickness of the secondary strata, or the depth of the adjoining sea.

When we have thus reduced to their true and proper scale those objects on the earth's surface which we consider greatest; and when we further consider that the theories of philosophy on the formation of the whole earth, are formed on a view of the minute portions of its diameter to which we have access, these portions, not being more than, at the very utmost, five miles in height, and, by analogy, five in depth, out of 8000 miles; how trifling does the theorist appear with his cabinets of minerals on which his theories are founded. Let him cast his mind's eye along the diameter of a section of the globe, and say if he is justified in forming theories of the mode of first formations on so slight a view of its mere surface.*

*It is not, perhaps, surprising, that the general views of mankind are, on such subjects, so very confined; for the globe itself is as much too large as the best artificial globes are too small for general uses.

In order to obviate, in some degree, both objections, I have occasionally formed a section of the earth upon a flat sandy beach, upon the scale of one inch to a mile; and I have found that such a scale materially assists the mind, in correcting false judgments on this extensive subject. We

Having thus corrected any false notions we may have formed, as to the comparative extent of objects within our view; and having thus attained the proper elevation from whence we may consider and study the Globe as a whole, let us now proceed to an attentive and unprejudiced consideration of it, from the earliest times of which we have any record, and examine whether that record is contradicted, or corroborated by the appearances we may discover. We find, then, that the most remote history opens with the assertion, that, "In the beginning God created the heaven and the earth; "but the earth was invisible and unfurnished, “and darkness was upon the face of the deep.”

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have thus a circle of 8,000 inches in diameter, or of 222 yards, which, when marked out with small stakes, upon a smooth surface, appears an immense area. Placing ourselves upon any part of this circumference, we have an opportunity of taking a just, though microscopic view of things as they are. The very highest mountain is, then, fully represented by five inches! the greatest depths of the ocean by the same little span! while we cannot calculate upon more than one inch as the medium variety of sea and land over the whole of this vast surface! In order to form an idea of smaller objects, we must examine an inch scale, finely graduated, and that, too, by the aid of a microscope ; and we shall thus find, that man would occupy about the 880th part of an inch in his proudest stature, or about the size of the smallest animalcula observed in fluids!