Arnold Guyot divides America into two continents.
Arnold Guyot, The Earth and Man: Lectures on Comparative Physical Geography (Boston: Gould, Kendall, and Lincoln, 1849), 29, 177–78
America repeats the same contrasts, although in a less decided manner. North America, like Europe, is more indented than South America, the configuration of which, in the exterior at least, reminds us of the forms of Africa, and the uniformity of its contours. The two continents of the New World are more alike. Nevertheless, the line of the shores is much more extended in North than in South America. It is 24,000 miles in the former, or one mile of coast to 228 square miles of surface; in the latter, it is 13,600 miles, or a mile of coast for 376 miles of surface.
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The New World has only two continents, North America and South America, America and Columbia, as I should like to call them to render justice where right belongs if it were not forbidden to change names consecrated by long usage. These two continents are not grouped in one mass, nor placed side by side, but separated from each other, not touching upon their long sides, but by their exterior angles, standing in line, rather than grouped. They are situated in two opposite hemispheres, and thus more distant from each other, apparently, and less neighboring.