A thorough exploration may justify this conjecture, but no data exists for fixing the absolute altitude at 164 feet. The value of the statements of Messrs. Cullen and Gisborne may be contested.
It will be seen from the altitude given in the table below, that however correct in point of fact these opinions may be, they are not sustained by the figures taken from the maps accompanying the Admiral’s report:
_Table showing the length of Railroads and Canals, length of Tunnels, altitudes of Summits, estimated cost of some of the lines proposed for uniting the two Oceans, from actual surveys_: ═══════════════════════╤═══════╤════════════╤════════╤═════════ │ │ LENGTH │ LENGTH │ALTITUDES ROUTES. │LENGTH.│ TO BE │ OF │ OF │ │CONSTRUCTED.│TUNNELS.│ SUMMIT. ───────────────────────┼───────┼────────────┼────────┼───────── │ MILES │ MILES │ MILES │ FEET Tehuantepec │ 190 │ │ │ 855 “ │ │ │ │ 843 Honduras │ 234 │ 234 │ │ 2956 Nicaragua to Realijo │ 298 │ 160 │ │ 174 “ “ Brito │ 194 │ │ │ 600 Panama │ 53⅔ │ │ 3.7 │ 459 “ │ 48 │ 48 │ │ 280 San Blas │ 30 │ │ 7 │ 1500 Darien to San Miguel │ 42 │ │ 7 to 8 │ 980 “ “ │ │ │ │ 1020 “ Lara to Sucubti │ │ │ │ 610? Atrato to Humboldt Bay │ 126 │ │ 3½ │ “ “ “ │ 149⅔ │ 52⅔ │ 2½ │ 970 “ to Cupica │ │ │ │ ───────────────────────┼───────┴────┬───────┴─┬──────┴───────────── │ │ CANAL │ AUTHORITIES ROUTES. │ ESTIMATED │ OR │ AND │ COST. │RAILROAD.│ REMARKS. ───────────────────────┼────────────┼─────────┼──────────────────── Tehuantepec │$ 16,900,000│ Canal. │ M. Moro. “ │ 7,847,896│Railroad.│ J. J. Williams. Honduras │ │ Canal. │ Trautwine. Nicaragua to Realijo │ 20,000,000│ “ │ Napoleon III. “ “ Brito │ 32,000,000│ “ │ O. W. Childs. Panama │ 27,000,000│ “ │ M. N. Garella. “ │ 50,000,000│ “ │ Col. G. W. Hughes. San Blas │ │ “ │ McDougal. Darien to San Miguel │ 65,000,000│ “ │ Gisborne. “ “ │ │ “ │ Prevost & Strain. “ Lara to Sucubti │ │ “ │ Bourdial. Atrato to Humboldt Bay │ 145,000,000│ “ │ Kennish. “ “ “ │ 134,450,154│ “ │ Lt. Michler, U.S.A. “ to Cupica │ 325,000,000│ “ │ Trautwine. ───────────────────────┴────────────┴─────────┴────────────────────
From the above table it would appear that the altitude of the dividing ridge falls off toward the two extremities of the Isthmus, viz.: near the Tehuantepec and the Atrato routes, but the greatest depressions have been found between Aspinwall and Panama, and on the line by the way of Lake Nicaragua and Lake Managua.