portions of it, as of the dry land, do not vary more than from a few hundred feet to half a mile, from positive smoothness.*

The greatest depths that have ever been reached by actual soundings, have seldom exceeded one mile. Captain Parry, however, in latitude 57 degrees 4 minutes north, longitude 24 degrees 34 minutes west, and about one hundred leagues from any land, found no bottom with the deep sea clamms, and a line of 1020 fathoms, or one mile and 280 yards, being more than a quarter of a mile deeper than was reached by lord Mulgrave.

Mr. Scoresby sounded in latitude 75 degrees 50 minutes north, longitude 5 degrees 50 minutes west, with 1058 fathoms; and in latitude 76 degrees 30 minutes north, longitude 4 degrees 48 minutes west, with 1200 fathoms of line, or one mile and 640 yards, in neither instance finding the bottom. This last is, probably, the greatest depth of soundings ever attempted.

The deepest mines that man has yet been able to form, do not reach, in perpendicular depth, much beyond two hundred fathoms, or not more than about a quarter of a mile. M. Humboldt saw, in 1803, a mine, in Mexico, which was to be sunk to the great depth of 1685 feet, or 280 fathoms, and which was to require twelve years for its completion, which, however, appeared very doubtful.

In viewing even volcanic action on the same great scale by which we have measured the mountains and the depths, we cannot consider these awful phenomena of burning mountains as more than superficial pustules on the mere skin of the earth.

* In the course of some late experiments at sea, on board H. M. sloop Trinculo, captain Booth, by order of the lords of the admiralty, in order to find soundings at unusual depths, Mr. Massey made use of several newly invented machines for this purpose.

He sunk a copper globe, capable of sustaining great pressure, with a line of 840 fathoms. The globe was enclosed in a strong net of cord, and was fixed close on the line, at about 40 fathoms from the lead. Neither globe nor lead returned to the surface; the globe had exploded, by the high pressure, and the line appeared as if blown off by an air-gun. A second globe was sunk, with a greater weight, and the same quantity of line, and it was inclosed in a still stronger netting, made of log-line, and not fixed so close to the line as in the former trial. In this instance the lead returned without having reached the bottom; but the globe had exploded, and the net was blown to pieces. These experiments proved, to the satisfaction of Mr. Massey and captain Booth, the impossibility of counteracting the effects of high pressure offered at great depths in the sea.

It is now pretty generally understood, and acknowledged, that water is one of the most active agents in the production of volcanic fires; and when we consider the number of volcanoes in the interior of our continents, which have, to all appearance, become extinct from the want of that communication with the 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 numbers 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 threw 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. Furguson, 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 Etna covered a space of fifty leagues in circumference, and one hundred and twenty feet in thickness, with calcare-' ous 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.*

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.'

I shall here adopt the corrected translation of the Mosaic record, from the numerous authorities, and unanswerable arguments brought forward by Mr. Granville Penn, in his admirable work, entitled, the "Comparative Estimate of the Mineral and Mosaical Geologies." That estimable writer has proved, in the most satisfactory manner, that the tohu vabohu of the Hebrew text, the without form and void' of our translation, was uniformly translated, both by the Septuagint, and

*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

use.

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 have thus a circle of 8000 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 depth 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!

by the Jewish and Christian churches, for 600 years subsequent to the Septuagint translation by the terms invisible, (from being covered with the waters) and unfurnished, from having, as yet, no vegetation.*

It is one of the great triumphs of human intellect, that the globular form of the earth is proved to demonstration; and to this has been added, by the immortal Newton, the certain knowledge of that remarkable fact, that the globe is slightly flattened at the poles, and may, therefore, be termed rather an obtuse spheroid, than a perfect sphere.

This great and wise man, in considering the nature and origin of all things, has said, " it appears probable to me, that God, in the beginning, formed matter, in solid, massy, hard, impenetrable, and movable particles, of such sizes and figures, and with such other properties, and in such proportions to space, as most conduced to the end for which he formed them.

“All material things seemed to have been composed of the hard and solid particles above-mentioned, variously associated in the first creation by the counsels of an intelligent agent. For, it became him, who created them, to set them in order; and if he did so, it is unphilosophical to seek for any other origin of this world, or to pretend that it might rise out of chaos by the mere laws of nature; though, being once formed, it may continue by these laws for many ages."t

"When Newton had remarked, that the planets present to the sight figures of obtuse spheroids, and not of perfect spheres; when he had reflected upon the nature and properties of that particular figure, and had contemplated those orbs, as subjected in their revolutions to the opposing actions of gravity and centrifugal force, his penetrating mind at length discovered, that the rule of harmony and equilibrium between these two contending powers was only to be found in the figure of an obtuse spheroid.

"In order to render this fact plain to the understanding of

*Comp. Estim., vol. i. p. 173.

I must here acknowledge the very important services that have been rendered to science by this most able writer, who is the first that has clearly exhibited some of the most important, but obscure, truths of Scripture, in connection with physical facts, open to our examination. It is only to be regretted, that the necessarily controversial character of the comparative estimate, renders it a work more suited to the mind of the learned than of the general reader. + Optics, Lib. 3.