PROJECTS FOR CANALS UNITING THE TWO OCEANS. 41 



PROJECTS FOR CANALS UNITING THE TWO OCEANS. 



It will also be proper, in conclusion, to offer some observations on a 

 subject which may be considered worthy of interest here, from its ap- 

 parent connection with the destinies of North- West America. 



The only means of communication for vessels between the Atlantic 

 and the Pacific Oceans at present known or believed to exist, are through 

 the seas south of the southern extremities of America and Africa ; and 

 each of these routes being circuitous and dangerous, the question as to 

 the practicability of a canal, for the passage of ships through the central 

 parts of the American continent where those seas are separated by narrow 

 tracts of land, has been frequently agitated. Humboldt, in his justly- 

 celebrated essay on Mexico, indicated nine places in America, in which 

 the waters of the two oceans, or of streams entering into them respec- 

 tively, are situated at short distances apart. Of these places it is necessary 

 here to notice but three, to each of which attention has been strongly 

 directed, at different times, and especially of late years, in the expectation 

 that such a navigable passage for ships might be effected through it. 

 They are, — the Isthmus of Panama — Nicaragua — and the Isthmus 

 of Tehuantepec. 



With regard to the last-mentioned of these places, it has been deter- 

 mined, by accurate surveys, that the mountain chain, separating the two 

 oceans, is nowhere less than a thousand feet in height above the level 

 of the sea: and that a canal connecting the River Guasecualco, flowing 

 into the Mexican Gulf, with the Pacific, must pass through an open cut 

 of nearly that depth, or a tunnel, in either case more than thirty miles 

 in length, as there is no water on the summit to supply locks, should it 

 be found practicable to construct them. The Isthmus of Tehuantepec, 

 however, offers many advantages for travellers, and even for the trans- 

 portation of precious commodities, especially to the people of the United 

 States. The mouth of the Guasecualco River, on its northern shore, is 

 less than seven hundred miles from the mouth of the Mississippi, and 

 only one hundred miles by the road from a port on the Pacific, near 

 Tehuantepec, which might be made a good harbor; so that even now a 

 traveller might go in a fortnight from Washington to the Pacific coast, 

 and thence, by a steam vessel, in ten days more, to the mouth of the 

 Columbia, or to the Sandwich Islands. 



In Nicaragua, it has been proposed to improve the navigation of the 

 San Juan River, from its mouth on the Mosquito coast, to the great 

 Lake of Nicaragua, from which it flows, or to cut a canal from the 

 Atlantic to that lake, whence another canal should be made to the 

 Pacific. Now, without enumerating the many other obstacles to this 

 plan, any one of them sufficient to defeat it, were all things besides favor- 

 able, it may be simply stated, that one mile of tunnel and two of very 

 deep cutting through volcanic rock, in addition to many locks, will be 

 required in the fifteen miles, which, by the shortest and least difficult 

 route, must be passed between the lake and the Pacific. Is such a work 

 practicable ? 



The Isthmus of Panama remains to be considered. From recent and 

 minute surveys, it has been proved that no obstacles to a ship-canal are 

 presented by the surface of this isthmus, equal to those which have been 



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