directly over the place, but some time after it has declined thence. The sea, in this case, being obstructed, pursues the moon with what dispatch it can, but does not arrive with all its waters, till after the moon has ceased to operate. Lastly, from this shal-. lowness of the sea, and from its being obstructed by shoals and straits, we may account for the Mediterranean, the Baltic, and the Black Sea, having no sensible tides. These, although to us they seem very extensive, are not, however, large enough to be affected by the influence of the moon; and, as to their communication with the ocean through such narrow inlets, it is impossible, that in a few hours they should receive and return water enough to raise or depress them in any considerable degree.

In general we may observe, that all tides are much higher, and more considerable in the torrid zone, than in the rest of the ocean; the sea in those parts being generally deeper, and less affected by variable winds, or winding shores. One of the greatest tides we know of is that at the mouth of the river Indus, where the water rises thirty feet in height. How great, therefore, must have been the amazement of Alexander's soldiers at such a strange appearance. They who had been always accustomed before to the scarcely perceptible risings of the Mediterranean, or the minute intumescence of the Black Sea, when made at once spectators of a river rising and falling thirty feet in a few hours, must, no doubt, have felt the most extreme awe, and, as we are told by Quintus Curtius, a mixture of curiosity and apprehension. The tides are also remarkably high on the coasts of Malay, in the straits of Sunda, in the Red Sea, at the mouth of the river St. Lawrence, along the coasts of China and Japan, at Panama, and in the gulf of Bengal. The tides at Batsha in the kingdom of Tonquin, which lies in 20° 50′ north latitude, are, however, the most remarkable in the world. In this

port there is but one tide and one ebb in twenty-four hours; whereas, as before observed, in all other places there are two. Besides, there, twice in each month there is no tide at all, when the moon is near the equinoctial, the water being for some time quite stagnant. These, with some other odd appearances, were considered by many as inscrutable; but Sir Isaac Newton, with peculiar sagacity, adjudged them to arise from the concurrence of two tides, one from the South Sea, and the other from the Indian Ocean. Of each of these tides there come successively two every day; two at one time greater, and two at another that are less. The time between the arrival of the two greater is considered by him as high tide; the time between the two less, as ebb. In short, with this alone, that great mathematician solved every appearance, and so established his theory as to silence every opposer.

Such is the nature and such the various phenomena of the tides; a subject which I cannot conclude without suggesting how much we are bound to adore the benevolent Creator, not only in the goodness which he manifests in the terraqueous globe, but in his astonishing world of waters. The waters of the sea, it has been observed by philosophers, are kept sweet by their motion, without which they would soon putrefy, and spread universal infection. If we look, therefore, for final causes, a great and obvious one is apparent in the tides. Had the sea been made without motion, and resembling a pool of stagnant water, the nobler races of animated nature would shortly have been at an end. Nothing would then be left alive but swarms of ill formed creatures, with scarce more than vegetable life, and subsisting by putrefaction. Were this extensive bed of waters entirely quiescent, millions of the smaller reptile kinds would there find a proper retreat in which to breed and multiply. They would find there no agi

tation, no concussion in the parts of the fluid to crush their feeble frames, or to force them from the places in which they were bred; there they would multiply in security and ease, enjoy a short life, and putrefying, thus again give life to numberless others, as little worthy of existence as themselves. But the motion of this great element effectually destroys the number of these viler creatures: its currents and its tides produce continual agitation, the shock of which they are not able to endure; the parts of the fluid rub against each other, destroy all viscidities; and, if I may so express myself, the ocean acquires health by exercise.

No. LVIII.

ON VARIOUS PHENOMENA OF THE OCEAN.

With wonder mark the moving wilderness of waves,
From pole to pole through boundless space diffused,
Magnificently dreadful! where, at large,

Leviathan, with each inferior name

Of sea-born kinds, ten thousand thousand tribes,
Finds endless range for pasture and for sport.
Adoring own

The Hand Almighty, who its channelled bed
Immeasurable sunk, and poured abroad,
Fenced with eternal mounds, the fluid sphere;
With every wind to waft large commerce on,
Join pole to pole, consociate severed worlds,
And link in bonds of intercourse and love
Earth's universal family.

MALLET.

IF we look upon a map of the world, we shall find that the ocean occupies a considerably greater surface of the globe than the land is found to do.

This immense body of waters is diffused round both the old and new continent to the south, and may surround them also to the north, for what we know; but the ice in those latter regions has stopped our inquiries. Although the ocean, properly speaking, is but one extensive sheet of water, continued over every part of the globe, without interruption, and although no part of it is divided from the rest, yet geographers have distinguished it by different names; as the Atlantic or Western Ocean, the Northern, Southern, Pacific, Indian, and German Oceans.

In this vast receptacle, almost all the rivers of the earth ultimately terminate. And yet these vast and inexhaustible supplies do not seem to increase its stores; for it is neither apparently swelled by their tribute, nor diminished by their failure: it continues constantly the same'. Indeed, the quantity of water of all the rivers and lakes in the world is nothing

Not only does the quantity of water in the ocean remain constantly the same, but, notwithstanding its most violent and incessant motion, it continues stable within certain limits. This, however, is what cannot be inferred from observation. For, although in the almost infinite variety of disturbances to which the ocean is liable, from the action of irregular causes, it may appear to return to its former state of equilibrium; yet we may nevertheless apprehend that some extraordinary cause may communicate to it a shock, which, though inconsiderable at its origin, may augment continually, and elevate it above the highest mountains. It is, therefore, interesting to investigate the conditions which are necessary for the absolute stability of the ocean. The celebrated Laplace has effected this; he has demonstrated that the equilibrium of the ocean must be stable if its density be less than the mean density of the earth; and that is known to be the case. He has likewise determined, by means of his refined analysis, that this stability would cease to exist, if the mean density of the sea exceeded that of the earth: so that the stability of the equilibrium of the ocean, and the excess of the density of the terrestrial globe above that of the waters which cover it, are reciprocally connected with each other; and indicate wisdom and contrivance in such a mutual adjustment.

compared to that contained in this prodigious reservoir. And some natural philosophers have carried their ideas on this subject so far, as to assert, in consequence of certain calculations, that, if the bed of the sea were empty, all the rivers of the world flowing into it with a continuance of their present stores, would take up at least 800 years to fill it again to its present height.

Thus great is the assemblage of waters diffused round our habitable globe; and yet, immeasurable as it seems, it is rendered subservient principally to the necessities and conveniencies of so little a being as man. Some have perceived so much analogy to man in the formation of the ocean, that they have not hesitated to assert it was made for him alone. This has been denied by others; and a variety of arguments have been adduced on both sides, in which I do not think it necessary to enter here: for, of this we are certain, that the great Creator has endowed us with abilities to turn this great extent of waters to our own advantage. He has made these things, perhaps, for other uses; but he has given us faculties to convert them to our own. This much agitated question, therefore, seems to terminate here: we shall never know whether the things of this world were made for our use; but we very well know that we were made to enjoy them. Let us then boldly affirm, that the earth and all its wonders are ours, since we are furnished with powers to force them into our service. Man is the lord of the whole sublunary creation; the howling savage, the winding serpent, with all the untameable and rebellious off spring of nature, are destroyed in the contest, or driven at a distance from his habitations. The extensive and tempestuous ocean, instead of dividing or limiting his power, only serves to assist his industry, and enlarge the sphere of his enjoyments. Its billows, and its monsters, instead of presenting a