General Michler, in his interesting report of the survey of the Atrato, observes: “All the stratified rocks on the Isthmus, exhibiting strong marks of disturbance and even dislocation since they were originally deposited, clearly prove that the upheaval which brought this narrow neck of land above the level of the ocean must have taken place at a comparatively late era. This period was undoubtedly accompanied by the protrusion of certain metamorphosed shistose (?) rocks, the doubtful nature of which has induced us to mark them as belonging to a trappean series. If Darwin had good reason to believe that the granite of South America, now rising into central peaks 14,000 feet in elevation, must have been in a fluid state since the deposition of the tertiary group, we may also do so in pronouncing the formation of the Isthmus, now linking together South and Central America, as decidedly post-tertiary.” The deductions of Columbus were, however, based on the direction of the coast of Cuba, which he supposed to be a continent, and the parallel coast of South America; and was further confirmed by the westerly current flowing between them, which must, he thought, find an outlet near Darien. These bold generalizations, drawn from stores of profound observation and varied reading, although we now know them to be erroneous, evince the sagacity of the man, and place him far ahead of the intelligence of his age. With heartfelt sorrow he reluctantly renounced a chimera so plausible, which he expected would lead him to the fabulous kingdom of Prester John, or, perhaps, to the marvelous splendors of the imperial dominions of Kublai Khan, and which would, he believed, open new fields for the peaceful conquests of the banner of the Redeemer. The delusive representations of travelers was the chief impulse to some of the greatest achievements of the fifteenth and sixteenth centuries. The coveted wealth of “Ormus and of Ind” was a siren who had lured adventurous navigators to dare the dangers of unknown seas. The same diversity of motive may be found in the men of that period which now exists and animates the westward course of civilization. Love of money and fame are found contending by the side of the desire to extend the domain of knowledge and zeal for the spread of religion. The result of these combined passions was to open new avenues to wealth, industry, and science. Four hundred years have elapsed since the wondering eyes of Spanish discoverers first gazed on the strange beauty of the New World. In this interval a nation of forty millions of people have been planted in the country of Columbus, its wildernesses are traversed by steam, its products supply food and clothing to a large part of the world; but, with all this progress, the visionary strait of the great navigator is yet an unrealized dream.