mit, contrary to the received opinion, that the Atlantic is a little higher than the South Sea. Trivial causes of a local nature, such as the con. figuration of the coast, currents and winds (as in the Straits of Babelmandel), may trouble the equilibrium which ought necessarily to exist be tween all the parts of the ocean. As the tides rise at Portobello to a third part of a metre *, and at Panama to four or five metres †, the levels of the two neighbouring seas ought to vary with the different establishments of the ports. But these trivial inequalities, far from obstructing hydraulical operations, would even be favourable for sluices.

We cannot doubt that if the isthmus of Panama were once burst by some similar catastrophe to that which opened the columns of Hercules ‡, the current of rotation in place of ascending towards the gulf of Mexico, and issuing through the canal of Bahama, would follow the same parallel from the coast of Paria to the Philippine islands. The effect of this opening, or new strait, would extend much beyond the banks of Newfoundland, and would either occasion the disappearance or diminish the celerity of the Hotwater river, known by the name of Gulf-stream §,

*13 inches. Trans.

+ 13 or 16 feet. Trans. Diodorus Siculus, lib. iv. p. 226. lib. xvii. p. 533. edit.

Rhodom.

§ The Gulf-stream, on which Franklin, and afterwards

i

which, leaving Florida on the north-east, flows in the 40° of latitude to the east, and especially the south-east towards the coast of Africa, Such would be the effects of an inundation analogous to that of which the memory has been preserved in the traditions of the Samothracians. But shall we dare to compare the pitiful works of man with canals cut by nature herself, with straits like the Hellespont and the Dardanelles !

*

Strabo appears inclined to believe that the sea will one day open the isthmus of Suez. No such catastrophe can be expected in the isthmus of Panama, unless enormous volcanic convulsions, very improbable in the actual state of repose of our planet, should occasion extraordinary revo, lutions. A tongue of land lengthened out from east to west in a direction almost parallel to that of the current of rotation escapes, as it were, the shock of the waves. The isthmus of Panama would be seriously threatened, if it extended from

Williams, have left us such valuable observations, carries rapidly the tropical waters to the northern latitudes. It is occasioned by the current of rotation which strikes against the coasts of Veragua and Honduras, and ascending towards the gulf of Mexico, between Cape Catoche and Cape St. Antoine, issues through the canal of Bahama. It is owing to this motion that the vegetable productions of the Antilles are carried to Norway, Ireland, and the Canaries. See the second volume of my Voyage to the Tropics, chap. i.

Strabo, ed. Siebenkees, T. I, p. 156.

south to north, and was situated between the port of Carthago and the mouth of the Rio San Juan, if the narrowest part of the new continent lay between the 10° and the 11° of latitude.

The navigation of the river Chagre is difficult, both on account of its sinuosities and the celerity of the current, frequently from one to two metres per second. These sinuosities however afford a counter current, by means of which the small vessels called bongos and chatas, ascend the river, either with oars, poles, or towing. Were these sinuosities to be cut, and the old bed of the river to be dried up, this advantage would cease, and it would be infinitely difficult to arrive from the North Sea to Cruces.

From all the information which I could procure relating to this isthmus, while I remained at Carthagena and Guayaquil, it appears to me, that the expectation of a canal of seven metres † in depth, and from twenty-two to twenty-eight metres‡ in breadth, which, like a pass or a strait, should go from sea to sea, and admit the vessels which sail from Europe to the East Indies, ought to be completely abandoned. The elevation of the ground would force the engineer to have recourse either to subterraneous galleries, or to the system

* From 3.28 to 6.56 feet. Trans.

† 22 feet 11 inches. Trans.

From 72 feet 2 inches, to 91 feet 10 inches. Trans.

of sluices; and the merchandizes destined to pass the isthmus of Panama could only therefore be transported in flat-bottomed boats unable to keep the sea. Entrepots at Panama and Portobello would be requisite. Every nation which wished to trade in this way would be dependent on the masters of the isthmus and canal; and this would be a very great inconvenience for the vessels despatched from Europe. Supposing then that this canal were cut, the greatest number of these vessels would probably continue their voyage round Cape Horn. We see that the passage of the Sound is still frequented, notwithstanding the existence of the Eyder canal, which connects the ocean with the Baltic sea.

It would be otherwise with the productions of western America, or the goods sent from Europe to the coast of the Pacific Ocean. These goods would cross the isthmus at less expense, and with less danger, particularly in time of war, than in doubling the southern extremity of the new continent. In the present state of things, the carriage of three quintals on mule-back from Panama to Portobello costs from three to four piastres (from 12s. 6d. to 16s. 8d.) But the uncultivated state in which the government allows the isthmus to remain is such, that the carriage of the copper of Chili, the quinquina of Peru, and the 60 or 70,000 vanegas of cacao* annually exported

A vanega weighs 110 Castilian pounds.

by Guayaquil, across this neck of land, requires many more beasts of burden than can be procured, so that the slow and expensive navigation round Cape Horn is preferred.

In 1802 and 1803, when the Spanish commerce was every where harassed by the English cruizers, a great part of the cacao was carried across the kingdom of New Spain, and embarked at Vera Cruz for Cadiz. They preferred the passage from Guayaquil to Acapulco, and a land journey of a hundred leagues from Acapulco to Vera Cruz, to the danger of a long navigation by Cape Horn, and the difficulty of struggling with the current along the coasts of Peru and Chili. This example proves, that, if the construction of a canal across the isthmus of Panama, or that of Guasacualco, abounds with too many difficulties from the multiplicity of sluices, the commerce of America would gain the most important advantages from good causeways, carried from Tehuantepec to the Embarcadero de la Cruz, and from Panama to Portobello. It is true that in the isthmus, the pas-. turage *to this day is very unfavourable to the nourishment and multiplication of cattle; but it would be easy, in so fertile a soil, to form savannas by cutting down forests, or to cultivate the

The assertion of Raynal (T. IV. p. 150) that domestic animals transported to Portobello lose their fecundity, should be considered as totally destitute of truth.