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Great American Isthmus.
in two great expeditions were built, at the mouth of the Chimalapa, with wood felled in the neighbouring forests of Tarifa, and other materials imported by the Coatzacoalcos. It would seem, indeed, that even after the hope of discovering a strait through the isthmus had faded away, the sagacious mind of Cortes was fully impressed with the topographical advantages of this region; for here he selected for himself the estate whence he derived his title as marquis. Now, as is remarked by M. Moro (M. de Garay's chief engineer, and author of the report), it is not easy to explain why in the midst of a country so prodigiously fertile the conqueror should have chosen for his own domain the only portion of it comparatively unproductive, unless he clearly foresaw that any mode of communication to be afterwards effected between the two oceans must necessarily pass over this ground.
It was now certain that no strait, connecting the Atlantic and the Pacific, existed in the neighbourhood of the Gulf of Mexico; but still the search was prosecuted further north. The English took up the work which the Portuguese abandoned, and began, at the close of the sixteenth century, those efforts for the discovery of the North-west Passage, which have been pushed to their utmost limits in our own day, and which have ended in clearly establishing this conclusion: that recourse must be had to artificial means, if the nations of Europe and their American progeny would realise the idea which they have pursued for three centuries and a half with such extraordinary ardour and pertinacity.
The American isthmus reaches from Tehuantepec and the Coatzacoalcos on the north, to Darien on the south, a length of five hundred and seventy-five leagues, and is traversed through its whole extent by a range of mountains, continuous at either extremity with the great chains that form the spines of both continents. Nine different parts of this isthmus have been proposed, at various times, as offering special facilities for effecting the desired communication; but it was at length ascertained that only three of these localities were worthy of consideration; those, namely, which, from their principal towns, are respectively designated Isthmus of Panama (properly so called), of Nicaragua, and of Tehuantepec.
The distance from ocean to ocean, across the Isthmus of Panama, is only forty miles. Were our judgment, therefore, to be formed from a mere inspection of the map, an inclination to consider this point the most eligible would be inevitable. The space that divides the two seas is greater at Nicaragua, namely, ninety-five miles, but being intersected by a lake of vast di
VOL. XXXIV. NO. LXVIII.
mensions, this tract of country would also appear to offer considerable advantages. Lastly, the territory of Tehuantepec, forming a continued line of 130 miles, is that which, upon a superficial examination, appears to be the least suited for the accomplishment of the object contemplated.
"However, notwithstanding these appearances, as a greater or less distance is not the only circumstance to be considered, it precisely happens in the three above-mentioned instances that the practicability of the work is in an inverse ratio to the shortness of the distance; and thus, while in the present state of our knowledge, it is apparently impossible at Panama, and attended with immense difficulties at Nicaragua, we find it practicable and easy at Tehuantepec."-Moro.
It is known that a special survey of the Isthmus of Panama has recently been made by order of the French government. The report has not been published, but it is generally supposed to be unfavourable. Even supposing, what is by no means certain, that the nature of the ground offered no formidable engineering difficulties, there are others quite sufficient to condemn the project, and these are, unfortunately, insurmountable. In the first place, it is absolutely necessary that the proposed canal, wherever executed, shall be navigable, from sea to sea, by trading vessels of a large class, without their being compelled to discharge their cargoes. Works on a smaller scale would, indeed, confer vast benefits on the country through which they passed, and these would, no doubt, react indirectly on Europe: but they could never offer the great commercial nations of the Old World such advantages as should induce them to lend the undertaking that financial aid, without which there seems no likelihood of its accomplishment. Now, as M. Chevalier observes:
"This condition of a maritime canal which shall permit vessels from Europe or the United States to hold on their course, from ocean to ocean, without unloading, and to reach their respective destinations at Lima, Acapulco, or Macao, infers another likewise which must not be overlooked. The canal must be in immediate connexion with the deep sea. Each of its extremities must open into a port affording suitable anchorage to vessels, not merely at a certain distance from the shore, but close up against the land. In many harbours, that of Panama for instance, the anchorage is at some distance from the land, and the loading and unloading of vessels is effected by means of boats. is but a trifling inconvenience in a port where the voyage terminates; it adds a little to the cost of shipping or unshipping the cargo, and that is all. But at either extremity of an oceanic canal it would be nothing less than a full stop put to a vessel's course: it would be as effectual in this way as a wall a hundred feet high stretched right across the middle of the canal. This supplementary clause in the programme
Great American Isthmus.
will not be easy to fulfil [in Panama], and an accomplished captain in our royal navy, just returned from a cruise off the isthmus, told me with very great reason, that it seemed to him likely to occasion more trouble than the cutting even of a canal five or six mètres deep between the two oceans. Lastly, this maritime canal must, of necessity, be free from tunnels. In fact, to make these passable for ships, even with their topmasts struck, their arches should be loftier than that of Posilippo, unless ship-builders devise some way by which all the masts can easily be laid level with the deck."
M. Chevalier likewise observes very justly, that among the cir cumstances to be kept in view in selecting the line of the canal, one of the most important is its salubrity. However great, he says, might be the saving of time cilected by steering through the isthmus, it would always be shunned by vessels if it were to prove a charnel-house. Now the climate of the Isthmus of Panama is confessedly noxious, a fact confirmed by Humboldt and other writers. To this grievous cause is to be ascribed the paucity of population, and the want of the necessary means of existence in that isthmus; and as the climate does not permit the increase of the former, there is no possibility of augmenting the latter.
"The population is thinly scattered, and generally not well-disposed to work...... The presumption is, that it would be necessary to bring over masons, miners, and even excavators, from Europe. Were the natives even willing to work they have not the requisite skill......On the other hand there is a fearful responsibility involved in the act of transporting European workmen to the isthmus. The climate is in fact a dangerous one for all who have not been born in it, or who are not prepared for it, but it is deadly for all who expose themselves to the heat of the sun, or who inhale the miasmata of the marshes, and those which always issue from the soil when recently turned up. necessary to find shelter for the workmen, to encamp them, and to proIt would be vide for all their wants; it would be necessary to lay down strict rules for the preservation of their health, and what is far more difficult, even with every means supplied them, to make them observe those rules in spite of the temptations strewn in their way. During the six months of the rainy season, from May to October, all operations in the open air must necessarily be suspended. What should be done then with the multitude? How protect them from the diseases of the country and from all the mischiefs engendered by idleness?"-Chevalier.
The Isthmus of Nicaragua possesses a fertile territory, a healthy climate, and is not deficient in population. Its breadth, measured directly from the port of San Juan de Nicaragua, is ninety-five miles; obliquely, from the same point to San Juan south on the Pacific, it is 155; and from San Juan de Nicaragua to Realejo, it is more than 250 miles. But by far the greater part of this
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space is occupied by the Lakes Leon and Nicaragua, the deep river Tipitapa, which flows from the former into the latter, and the ample bed of the San Juan, by which the Lake of Nicaragua pours its waters into the Atlantic. The resemblance between this noble body of water and the chain of lakes which has been converted into the Caledonian canal cannot be overlooked, and the probability seems strong, on a first view, that nature has here laid down the basis of a great oceanic communication, which invites the fashioning hand of man to complete it. As to harbours on either coast, all accounts speak favourably of that of San Juan on the Atlantic side. Mr. Bailey, of the English navy, says, it is unexceptionable,' but small; whilst all other testimonies agree in attributing to it considerable extent. MM. Rouhand and Dumartray say it is vast and perfectly safe,' and according to M. Chevalier, some skilful members of the French marine, sent to examine it in 1843, expressly declare that it is a vast and safe asylum, a fine situation, an excellent port, with a good_anchorage close to the land.' On the Pacific we have San Juan south, which, however, is inadequate from its small dimensions; a score of vessels it is said would be enough to fill it. But further north, nearly coinciding with the direction of the axis of Lake Leon, is Realejo, one of the finest harbours in the world. Hence, and on account of the nature of the ground between the lake and San Juan south, which would render a tunnel inevitable in that direction, it is probable that if ever a Nicaraguan canal shall be constructed, it will be in the direction of the longest of the three lines specified above. Its actual length, when completed, would probably be about 300 miles. The portion of this space occupied by the lakes and by the Tipitapa would need no outlay, except an inconsiderable one to enable vessels to pass one fall of thirteen feet in that river: but the difficulties on the other parts of the line would probably be formidable.
The course of the river San Juan, with all its windings, is about ninety-five miles in length, more than four miles of which are obstructed by four rapids, caused by banks of rocks stretching across the whole width of the river. These obstacles have been considered so formidable as to suggest the construction of a lateral canal, as an easier operation than that of rendering the river itself navigable for large vessels; and the cost of this work alone, taking the average engineering prices of the United States as a standard, has been estimated by Mr. Stephens, from data furnished by Mr. Bailey, as amounting to ten or twelve millions of dollars.
Unfortunately we have as yet no certain data to enable us to say what may be the amount of difficulty to be overcome between the
Great American Isthmus.
extremity of Lake Leon and the Pacific. All we know is, that from Moabita, at the north-west point of the lake, the distance to Realejo is twenty-two miles, and to Tamarindo, another port on the same shore, nine miles, and that the nature of the ground is apparently favourable. All this country is yet to be explored. These regions, so interesting as regards the commerce of the whole world, so fascinating by their beauty, their wondrous fertility, and the exquisite charms of their climate, have hitherto been less frequented by inquiring travellers than the inhospitable steppes of Tartary, and the burning or icy deserts of Africa or the pole. It is said, that the crest to be surmounted or cut through, is probably not much elevated above the level of the lake; but that a great number of locks would be indispensable in order to descend from the level of Lake Leon to that of the Pacific, the difference between these two being forty-eight mètres (157 feet).
One fact must by no means be left out of consideration in discussing the Nicaraguan line. There is not,' says Humboldt, 'on the face of the globe another spot so thickly studded with volcanoes as that part of America which lies between the 11th and 13th degrees of northern latitude.' These volcanoes, and the earthquakes, which are their sure concomitants, are of evil omen for the success of the project.
We come now to the Isthmus of Tehuantepec, the first chosen and long regarded as the most eligible point for the great work, the execution of which was definitively appointed to take place here by a decree of the Spanish cortes, dated April 30, 1814. Then came the war of independence; and, when peace was restored, and the government of Mexico returned to the consideration of the project, the isthmus unhappily fell into unmerited discredit, in consequence of the grossly erroneous reports made by General Orbegozo, who was sent to survey it, much against his will, and with instrumental and other means ridiculously inadequate to the task he had to perform. The recent labours of Signor Moro and his associates have completely reversed the false judgment pronounced on the isthmus by General Orbegozo, and adopted by M. Chevalier on his authority in the work named at the head of this article.
The breadth of the isthmus in a straight line from the mouth of the Coatzacoalcos is 220 kilomètres (130miles), but the greater part of this space is occupied on the south by lagoons and extensive plains, and on the Atlantic side by the course of the Coatzacoalcos, which can easily be rendered navigable up to its confluence with the Malatengo. The principal works, therefore, to be executed would be comprised between latitude 16° 36′ and 17° 3' N., including a space less than thirty-one miles in extent, wherein no excavation whatever exceeding the usual limits would be required. The highest point to be surmounted is at the Portello de