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between the waters, and reluctance on the part of the Gulf Stream to mingle with the common waters of the sea." The Gulf of Mexico is the cauldron from which this extraordinary stream is supplied. The water comes through the Straits of Florida at no less a temperature than 90 degrees; and what is more wonderful, it sustains its heat for a distance of 3000 miles, and when opposite to Newfoundland the heat is not reduced to less than 75 degrees. This river of hot water, 500 or 600 miles broad, and averaging two miles deep, is constantly rushing through the Atlantic Ocean; the cold water at each side and at the bottom of it. It never touches the bottom, but proceeds through a channel of the ocean, which is as distinctly marked as the bed of any river in the world. It has always been flowing from the coast of America, runs up towards Newfoundland, then turns in a more north-easterly direction, speeds away to the North-eastern Seas, washes the shores of Ireland and Scotland, and even Spitzbergen, but does not encircle England; then turns off southward to the Bay of Biscay, and, taking a south-western course gradually getting cooler and cooler, it meets the equatorial current, and returns as a cold-water river into its cauldron. So has it been rolling round and round, by a wonderful principle of Nature during all these years, and producing the most beneficial effects.
Another remarkable feature of this stream is, that it is a river which not only flows first to the north, then north-east, and then to the east, but the whole body has a horizontal motion upwards and downwards, according to the seasons. In summer, its course is 4 degrees, or 240 miles south of that which it is in winter. What first led to inquiries upon the Gulf Stream, was, that whales were never found near it; they could not cross the hot water, and were confined to a space the latitude and longitude of which Lieut. Maury has so well marked out, that the poor whales have little chance of escape from their pur
suers. The Americans (cunning folks that they are) knew the mysteries of the stream twenty years before they let John Bull into the secret. It was observed that the Falmouth packets were always a fortnight behind the American vessels ;-the fact being, that the Americans knew where the Gulf Stream was, and took advantage of it in sailing to England. At length Franklin told our government about it. To show the obstinacy of John Bull, when new charts were prepared, and instructions sent to Falmouth that the packets were to take advantage of the Gulf Stream, the captains turned round, and said, "they would not be taught by the Yankees.”
The grand object of the Gulf Stream is to carry away from that hot region of the world the superabundant heat, and to bring it to us who stand so much in need of it. It is one of the most beautiful contrivances on a gigantic scale ever presented to the mind of man.
The quantity of heat which the stream takes away from the Bay of Honduras, and the Gulf of Mexico, is enough on a winter's day to change winter into summer all over France and Great Britain. The wind blows for nine months over the hot waters, rendering the ocean tepid, and emancipating the British island from ice; whilst the air becomes warm, and sends its pleasant vapours over the whole of the western coasts of these islands. The products of the West Indies are drifted across to these shores; and it is not an uncommon thing to pick them upon the coasts of England, Ireland, and Scotland, while they are never cast on the American shores. The same
stream gives the mariner a fair tide; he has a fair tide from America to this country, and a fair tide back by the coldwater stream, which returns inside, or north of the Gulf Stream, in a south-west direction. When ships are covered with frost, and their rigging frozen, they takes place, and they are freed from their shackles have only to steer into the Gulf Stream, when a thaw.
Various theories have been propounded as to the cause of the Gulf Stream; but Lieut. Maury was the first man who had accumulated together sufficient evidence to place the subject on a philosophical basis. We must come to the principles of Nature, in order to explain the combination of causes which lead to this great result. In the first place, the sea is salt; geology establishes the fact that it has been so from the beginning. If it was not salt, none of these effects would be produced ; so that the saltness of the ocean is the key stone of the arch which will carry us over the difficulty. The winds have little or nothing to do with the currents; they are in the mightiest whirlwinds and storms but as little puffs upon the surface, and leave the deep sea currents calm beneath them. Then we know that water is a non-conductor of heat; that though it is capable of receiving the greatest amount of heat, it does not conduct it. This explains one great phenomenonthat the stream of hot water runs through the cold without mixing with it. There is the same indisposition to amalgamate between salt-water and fresh-water. In fact, water seems a very unsocial element, and won't mix with the same element under other conditions till it is forced. Another fact is, that water in motion will not mix with water at rest: so here we have those wonderful principles which illustrate the great river running through the ocean. The Gulf Stream never touches the earth at the bottom of the ocean. Why? if it did the heat would escape, as the earth is a conductor of heat. But there is below the stream a cushion of cold water, so that it runs through an entire channel of cold water, that it may conduct its heat 3000 miles across the ocean. Again, cold water is heavier than hot water, and salt water heavier than fresh water. All the currents of the ocean, in every part of the world, are occasioned by this one thing—the inequality in the weight of water.
causes produce this inequality in the weight of water-evaporation, precipitation, and, what is very curious, the third cause is the work of the little shelly creatures at the bottom of the ocean. The evaporation in part of the Atlantic Ocean would produce 15 feet of solid water in a year; and if it could be accumulated, it would cover three millions of square miles. Of course, if this was done all at once, it would destroy the world. If all the salt in the sea were precipitated, or made solid, it would cover more than half the continent of America a mile deep. There is nearly half an ounce of solid matter in every pound of sea water. If this matter were allowed to accumulate it would destroy the natural equilibrium. But God called the insects in; and the thousands of coral reefs in the Pacific Ocean are constantly in process of formation by these little creatures. Every shell-fish we picked up on the sea shore, took a portion of this matter upon its back, thus the accumulation of lime, soda, iron, &c., is prevented: the heat goes up in evaporation, and comes back to us in refreshing showers. So that we are indebted for our climate, to the wonderful labours of the millions of little creatures on the other side of the globe. They have power to put the whole sea in motion, from the equator to the poles.
Let us now turn our attention for a short time to the currents of the ocean. It is a remarkable fact, that (with the exception of Behring's Straits) where ever there is a surface current running one way, there is always an under current running in all opposite direction, perhaps two miles deep. Thus you see the currents of the ocean, like the circalation of the blood, if they all ran one way would cause disorganisation. But perhaps you are ready to say,-How do you know this? How can you tell there is an under current running five miles an hour? The method by which this is discovered, is a very ingenious and simple one. I will endeavour to
explain it to you. They take a large piece of wood, and weight it sufficiently to sink it as far as they please. They then attach a small barrel or float to it, with a line; and then a most beautiful phenomenon is the result, which greatly astonishes the sailors. The barrel or float sets off against wind or surface tide, as if it were drawn by some monster. I shall be very much surprised if “ Jack” doesn't make some more practical use of this fact, and sink something large enough to drag his ship along. It is upon the same principle, that while the great body of surface water comes dowu the Davis Strait, and with such power as to force the Gulf Stream into a horse shoe bend, an under current of great depth and force is running into that ocean.
The “Resolution," which as you may remember, was one of the vessels that went in search of Sir John Franklin,—was blocked up with ice, and abandoned by the crew in these Straits. It was found afterwards by an American vessel in the Atlantic, having been brought down upon a huge iceberg, by the foree of the surface current.
One large and single iceflaw brought down these Straits, was 300,000 square miles in extent, upwards of 7 feet thick, and eighteen thousand millions of tons weight.
The Strait of Gibraltar, which is very deep, passes into the Mediterranean Sea. Our forefathers, hundreds of years ago, knew the fact that the Atlantic is always rushing in at a great pace through this strait, and although there is no outlet, the Mediterranean is not enlarged, nor is the water any more salt than the ocean outside. How is this? There must be some secret way out for these waters, or the Mediterranean Sea would become like the Dead Sea, a mass of salt, and dry up. Where is the escape, then? The fact is, though there are those who deny it to this day—that there is a peaceful under current running out, as the top one runs in. O wi, di