Rambles by Land and Water; or, Notes of Travel in Cuba and Mexico

by Benjamin Moore Norman

In pursuing my adventures, I stopped frequently at the different milpas that lay in the way; but nothing like thrift or comfort was any where visible. A rude hovel with mud walls, and a single room, is all they aspire to, in the way of a dwelling. The land is rich and fruitful to excess, and the lounging, listless Indian is the only insurmountable obstacle to its profitable cultivation and improvement. In the hands of our southern planters, or of the sturdy farmers of the northern and western states, this whole region would become a paradise of perennial fruits and flowers, and teem with the golden treasures of every clime under heaven.

In some of the fresh water lakes, in the interior, the "chapoté," a species of asphaltum, is found bubbling up to the surface. When washed upon the borders, it is gathered, and used as a varnish upon the bottoms of canoes. It has a peculiar pungent smell, like that of liquid asphaltum, and possesses, I think, some of its qualities. I have observed a remarkable phenomenon, of the same kind, out of sight of land, in the Gulf of Mexico, where the waters bubble up in the same manner, and accompanied with a similar smell. There can be no doubt that the ebullition and effluvia observed in the Gulf, are the effect of the same cause, which produces the asphaltic substance on the surface of the Lakes.

This Asphaltic deposite in the Gulf, it appears, has attracted the notice of others, and from it a theory has recently been formed, to account for that hitherto unexplained, or not satisfactorily explained phenomenon, the Gulf Stream. The article appears in the August number of Hunt's Merchant's Magazine. As I had remarked upon the circumstance before that article was published, and furnished my remarks to the writer, as a confirmation of his statements, each of them having been made without a knowledge of the other, I think it not amiss to present, in this place, the substance of his theory, and the reasons upon which it is founded. I shall then have an opinion of my own to present, which differs materially from his.

The opinion of the writer is, that the Gulf Stream is not caused by the trade winds forcing into the Caribbean Sea, between the South Caribbee Islands and the coast of South America, a large quantity of water which can only find vent into the North Atlantic, by the Florida channel. In his view, there are serious objections to this theory. First, the water in the Gulf Stream is hotter than that of any part of the Atlantic, under the equator, and therefore it cannot be that, which supplies this never failing current. Secondly, the water of the Stream is hotter in deep water, where the current begins, or rather where it has become regular and strong, than it is in the Gulf, on soundings, where there is little or no current, indicating that it comes not from the shores, but from the bottom in deep water.

Thirdly, the appearance, in the Gulf, of bubbles of asphaltum constantly rising to the surface, and spread over it for a considerable distance. It has been collected in quantities sufficient to cover vessels chains, and other portions of the equipments. It is of a bituminous character, offensive to the smell, and becomes hard on exposure to the sun, forming a durable varnish, and doing better service on iron than any paint.

Fourthly, the volume of the Gulf Stream is sometimes so great, that the Florida channel is not sufficient to give it outlet, and the excess passes off to the south of the Island of Cuba. This has been noticed to such an extent, that vessels, in sailing across from Cape Catoche, the eastern extremity of Yucatan, to Cape Corientes or Antonio, are often driven by it very much to the eastward of their course. It is manifest that such a current could not exist, if the Gulf Stream were supplied by waters driven from that direction, as the two currents would counteract and destroy each other.

From these premises, the inference of the writer is, that nothing less than an ocean subsidiary to the Atlantic could supply the immense quantity of water, which is continually flowing out of the Gulf, with the force of an independent stream. And because this portion of the Atlantic is separated from the Pacific only by a narrow Isthmus, and the water in the Pacific is known to be constantly higher than that in the Atlantic, a passage under the Isthmus would necessarily create a powerful current. This passage he supposes to exist, to afford the supply necessary to keep the Gulf Stream perpetually in action. And, as the regions through which the supposed passage is formed, are known to be volcanic, the supposition accounts for the high temperature of the water, as well as for the force of the current.

With regard to the temperature of the water in the stream, it is stated, that its average, off the Capes of Florida, is 86°, and in latitude 36, it is 81°; while the mean temperature of the atmosphere, under the equator, is 74°, and of the water of the Atlantic, in the same place, not above 60°. It appears, then, that the water of the Stream, in passing out of the Gulf is some 26° hotter than that of the ocean, which, under the old theory, is supposed to supply it.

There is an error, either of the author, or of the printer, in these figures. The temperature of the Gulf Stream is correctly given; but he has evidently placed that of the ocean under the tropics, too low. It does not materially affect his argument, however, since it is undoubtedly a fact, notwithstanding the assertions of another writer, who has undertaken to reply to the article in question, that the water of the Gulf Stream, after it leaves the tropics, is warmer by some degrees, than the average of any part of the ocean under the tropics. On this point, the argument in Hunt's Magazine will not, I imagine, be controverted.

The suggestion, that the water which constitutes this stream, is derived from the Pacific, forced by its superior elevation there, through a subterranean passage, across or under the Isthmus, is certainly original, and ingenious. But, to my view, it is liable to as many objections, as the old one which it is intended to displace. It is indeed, as the writer says, a bold conjecture, having nothing to support it, except the volume of water required for the constant supply of the great stream, and the asphaltic ebullition, which first suggested the theory, and gave rise to the discussion. Both these circumstances, I imagine, can be disposed of in a very satisfactory manner, without resorting to the supposition of this mysterious communication between the two great oceans.