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moon must be admitted to exercise so decisive and commanding an influence on the earth, what then must be the influence of the earth upon the moon?-for we must suppose the operation to be reciprocal. And if the influence of the earth on the moon corresponds with its superior magnitude and importance, then are we authorized to suppose that the lunar oceans would be subject to a tremendous agitation indeed. How does this agree with the simplicity of nature's works, and her acknowledged wisdom and economy? I can imagine nothing more ridiculous than such suppositions, nor any thing more adverse to the general impressions of mankind, in relation to the decrees of eternal wisdom.
I think a plausible, and to my mind a very rational opinon, can be advanced, why it is that at the full and change of the moon we invariably see what are denominated spring tides. It is known that the earth acts to the moon as a moon, and that, according to the opinion of astronomers, as seen by the inhabitants of the moon, it is the 'most magnificent object visible in the heavens.' Now this harmony of action, this remarkable coincidence, in all probability fulfils a law that is of infinite importance to the moon and its inhabitants. It may be fairly presumed, without any extravagance, that whenever she reaches the above points in her orbit, she requires a greater portion of light to be thrown from the earth than is done under ordinary circumstances. For let it be remembered that at such times there are many more millions of acres of land covered with water than is the case with the usual tides, and that consequently the light is increased in that proportion, and reflected upon the moon in a corresponding degree. By this means, important objects may be accomplished; and while in countless ways the advantages may be felt by the earth, and its swarms of inhabitants, an equally important advantage may be conferred on the inhabitants of the moon. Here, it would seem to me, we may perceive some of the great and signal benefits imparted by a coincidence which is as wise as it is beneficial and beautiful.
Philosophers, however, have thought proper, from the fact of a forever recurring regularity, to invest in a secondary planet an allpowerful agency in the movements of the great oceans of the pri mary, and that too in direct contravention of all those plain and simple operations, which, as far as they are comprehended, agree so perfectly with the ordinary perceptions of mankind every where. And however universal may be such belief, I have no more faith in this presumed control of the moon, than I should have if I were told that by the same means our blood was propelled from the heart to the extremities, and back again to the heart. I should deem one quite as rational as the other, and quite as consistent with truth, and with those principles of order which are known to be 'heaven's first law.'
It is well known that under the line there is very little tide. Now this would appear extraordinary, if we are to believe that the influence of the moon is such as to produce tides so singular in their effects as continually occur. It must be clear to every one, that the surface of the earth under the line is much nearer the moon than it is in high northern or southern latitudes; and it would therefore
seem to follow, as a fair consequence, that there, owing to the con vexity of the earth, the tides ought to be much the highest. The fact, however, is precisely the reverse of this; showing, contrary to all established laws, that in proportion as we recede from the centre of power, or the first impulse, so it increases in force, and that too to a surprising extent. In New-York, for instance, the ordinary tides are about six feet, and even two in Albany; in Boston ten to twelve, and in the Bay of Fundy forty to fifty. How such facts are to be reconciled with that theory which places this wonderful influence in the moon, I am utterly unable to conceive. It appears to me to be wholly inconsistent with all those causes and effects with which we are most familiar, and disagrees entirely with those principles of philosophy which are known to be well established in other respects, and which so universally accord with the reasoning faculties and perceptions of men.
I think my notions will be still farther illustrated, by a reference to the Mediterranean, the Black, and the Caspian seas. Surely, these are of sufficient magnitude to be subject to the influence of the moon, if such influence existed; yet in the first named sea it is barely perceptible, and in the others it is not felt at all. The same remark will apply to the great inland seas of America, where it is known, also, there is not the slightest appearance of tide. Now if we admit that the moon does really exercise the extraordinary power ascribed to it, how can we account for its controlling power being thus partial? Why should its force be restricted to the great oceans only, and even on these found to operate so unequally? If in some places the tides are strong and full, in others they are partialand feeble. In a certain latitude on the Pacific, they rise very high, and in a corresponding latitude on the Atlantic, there is very little; the tides in both oceans making nearly at the same time.
THERE is one phenomenon in the Atlantic ocean, which may perhaps be considered its greatest wonder, but which remains the least satisfactorily explained. This is that extraordinary movement denominated the Gulf Stream, which commences in the Bay of Mexico, and stretches along contiguous to the whole coast of North America, and after sweeping in a circular manner almost across the ocean, is lost not far from the confines of Africa. This prodigious current is estimated, by some navigators, to be sixty miles in width, and to move, for an immense distance, at the rate of not less than twoand-a-half miles an hour.
Theories are not wanting to account for this inexplicable and deep mystery. The most prevalent, though by no means one that is satisfactory, is that which traces it to a great accumulation of water in the Bay of Mexico, occasioned by the trade winds, and which finds an outlet in this way. This would lead to the supposition that there must be a strong pressure from the Atlantic into the Caribbean Sea, and so around through the Bay of Mexico. But we have no knowledge of any such operation. Hence the explanation given I deem neither conclusive nor carrying with it a very strong probability. It is moreover disbelieved by many scientific men, of profound reflection and
observation. Nor can it be deemed the least singular feature in this great mystery, that the water is found to be of a considerably higher temperature than that on either side of it, and which indicates the usual degree of warmth in the ocean. Where shall we seek for the
source of this perpetual heat?
I shall here assume an hypothesis, which to some may seem strange, from its entire newness, but which, from long reflection, and the best view I have been able to take of the subject, appears to me the only correct one. That some portion of the substratum of the Bay of Mexico covers a vast volcano, there rests on my mind no manner of doubt. The high temperature communicated to the Gulf Stream can only be produced by such a cause; and I hesitate not to say, it can originate in no other. Hence the unceasing action and unchanging warmth of the water must proceed from its contiguity to a mighty deposite of unquenchable fires. Its natural effect is, to beget perpetual motion; and here, I think we are justified in believing, is the grand secret. This immense mass of heated water must have vent. There is but one way in which this can be accomplished, and that is, by making a current in an easterly direction. This must be the plain and simple operation, and that too for very obvious reasons. It cannot go south or west, for reasons that are at once evident and conclusive. The whole of that portion of the ocean comprised between North and South America and the West India Islands, partakes of a higher degree of warmth than any other; beside, in those directions, there is no escape; whereas the broad Atlantic to the east is colder, by many degrees, than is the case in the Caribbean Sea, and among the islands. How much more so, indeed, when we take into view the vast islands of ice which are floated by cold northern currents from the coasts of Greenland, Norway, etc., (and these currents I believe to be perpetual,) and which almost every season are encountered by vessels in temperate and even in warm latitudes. Here, in my opinion, are abundant causes, and the perfectly natural and true causes, why the Gulf Stream must necessarily take this course, and why it can take no other. It is neither more nor less than that wellestablished principle in physical laws, which seeks to bring about an equilibrium in the elements, wherever, by force of circumstances, an inequality is created. This operation is both natural and simple; and according to the view that presents itself to my mind, here are the concealed but actual agents, which occasion one of the most extraordinary movements in the ocean, that has ever engaged the attention of mankind. Whether there be a subterraneous communication between the Pacific and the Bay of Mexico, must be conjectural. Should my hypothesis be admitted as truth, it still remains a matter of amazement, and deep wonder. The chief cause can only exist in an immense deposite of those hidden fires which the Creator has treasured up in the bowels of the earth, to be called forth at the appointed time, and employed for inscrutable but wise purposes. The earthquakes that shook the Mississippi country, in such a frightful manner, a number of years ago, are ample proof of the existence of these fires. And that they do not burst forth and convulse the earth, in a way still more destructive and terrific, is no evidence that they will sleep for ever.
We have before us, then, the everlasting results of two inconceivably powerful as well as permanent impulses, one of which, according to general belief, (though I think most preposterously,) is lodged in the moon, and the other, by universal assent, admitted to exist in the earth itself. How such hypotheses are to be reconciled with each other, or with that plainness and simplicity which are indisputable characteristics of Nature, in her accustomed displays and purposes, and which in all cases, where understood, agree so well with the ordinary judgment and reasoning powers of men, is beyond the reach of my ken or comprehension.
HAVING expressed my entire disbelief in the prevailing theory that the tides are produced through the instrumentality of the moon, I shall now submit to the reader certain facts, which no one will presume to doubt, or attempt to controvert; and I think they will be found to corroborate my position, beyond the reach of dispute or cavil. They are the result of recent observations and experiments, and their authority cannot be questioned. The first in order here follows.
Observations copied from An Account of Levellings carried across the Isthmus of Panama, to ascertain the relative height of the Pacific Ocean at Panama, and of the Atlantic at the mouth of the river Chagres, accompanied by geographical and topographical notices of the Isthmus. By John Augustus Lloyd, Esq. Communicated by Capt. Sabine, Secretary of the Royal Society.'
By careful and continued observations, I found the rise and fall of the tide in the Pacific, at Panama, as follows: Between the extreme elevation and depression of the water by occasional tides, there is a difference of 27.44 feet, and the mean actual rise and fall, two days after full moon, 21.22 feet.
'At Chagres I observed the rise and fall of the tide at the close of the dry season, in April, 1829, to be 1.16 feet, and being there subsequently, during the rainy season, I had an opportunity of observing that the high water mark was the same in both seasons.
The time of high water is nearly the same at Chagres and at Panama, namely, at 3 h. 20 m., at full and change. Hence the following interesting and curious phenomena are deducible, in respect to the difference of level of the two seas:
1st. High water mark at Panama is 13.55 feet above high water mark of the Atlantic at Chagres. Half the rise and fall of spring tides at Panama is 10.61 feet, and at Chagres, 0.58 of a foot; and assuming half the rise and fall above the low water of spring tides to be the respective mean levels, the mean height of the Pacific at Panama is 3.52 feet higher than that of the Atlantic at Chagres.
2d. At high water, the time of which is nearly the same on both sides the Isthmus, the Pacific is raised at mean tides 10.61 feet, and the Atlantic 0.58 of a foot above their respective mean levels. The Pacific is therefore the highest at such times (10.61-0.58-3.52)
'3d. At low water, both seas are the same quantities below their respective mean levels; therefore at such times the Pacific is lower than the Atlantic by (10.61-0.55-3.52) 6.51 feet.
In every twelve hours, therefore, and commencing with high tides, the level of the Pacific is first several feet higher than that of the Atlantic; it becomes then of the same height, and at low tide several feet lower; again, as the tide rises, the two seas are of one height; and finally, at high tide, the Pacific is again the same number of feet above the Atlantic as at first.'
Several years since I became acquainted with an intelligent and well-educated American naval officer, who had traversed that region of country, and who confirmed the above facts, in all the essential particulars. He stated that in the Bay of Panama the ordinary tides were about twelve feet, and the spring tides frequently twenty-two. At the mouths of the Chagres and St. John's rivers, the ordinary tide was only a foot and seven or eight inches.
Here are two great contiguous oceans, in both of which the tides make nearly at the same time, and yet the difference in their elevation ascertained to be most extraordinary, and showing incontestibly that an agency very different from that presumed to be placed in the moon, is employed in producing this unexplained mystery.
The next important fact, and one on which entire reliance may be placed, is copied from Williams' Narrative of Missionary Enterprise in the South Sea Islands.' This is a work of unusual merit ; for, in addition to a full and very instructive detail of all the important circumstances immediately connected with his mission, it abounds with sketches of natural history, and with topographical and geographical remarks, the whole of which are highly interesting and valuable. An excellent edition of this work has been recently republished in New-York, by Messrs. Appleton and Company. The writer's remarks on the tides are:
Upon a variety of other interesting topics in reference to Rarotonga, I must be equally brief. Some, indeed, I must pass over altogether. An observation or two, however, upon the tides, should not be omitted. It is to the Missionaries a well known fact, that the tides in Tahiti, and the Society Islands, are uniform throughout the year, both as to the time of the ebb and flow, and the height of the rise and fall, it being high water invariably at noon and midnight, and consequently the water is at its lowest point at six o'clock in the morning and evening. The rise is seldom more than eighteen inches or two feet above low water mark. It must be observed, that mostly once, and frequently twice, in the year, a very heavy sea rolls over the reef, and bursts with great violence upon the shore. But the most remarkable feature in the periodically high sea, is that it invariably comes from W. and S. W., which is the opposite direction to that from which the trade wind blows. The eastern sides of the islands are, I believe, never injured by these periodical inundations.'
The third fact to which I shall refer, will be found in Topographical Sketches of Florida,' published a few years since. Not having the work at command, I must quote from memory. Speaking of the tides on the west coast of the peninsula, the writer says,