Sospesa sta fra le stelle sublime,
E laggiu son citta, castella, e imperio;
Ma nol cognobbon quelle gente prime.
Vedi che il sol di camminar s' affretta,
Dove io dico che laggiu s' aspetta.
Pulci, _Morgante Maggiore_, xxv. 229, 230.

This prophecy of western discovery combines with the
astronomical knowledge here shown, to remind us that the
Florentine Pulci was a fellow-townsman and most likely an
acquaintance of Toscanelli.]

[Sidenote: The idea was suggested by the globular form of the earth;]

[Sidenote: and was as old as Aristotle.]

[Sidenote: Opinions of ancient writers.]

However this may have been, the letter clearly proves that at that most
interesting period, in or about 1474, Columbus was already meditating
upon the westward route.[447] Whether he owed the idea to Toscanelli,
or not, is a question of no great importance so far as concerns his own
originality; for the idea was already in the air. The originality of
Columbus did not consist in his conceiving the possibility of reaching
the shores of Cathay by sailing west, but in his conceiving it in such
distinct and practical shape as to be ready to make the adventure in
his own person. As a matter of theory the possibility of such a voyage
could not fail to be suggested by the globular form of the earth; and
ever since the days of Aristotle that had been generally admitted by men
learned in physical science. Aristotle proved, from the different
altitudes of the pole-star in different places, that the earth must
necessarily be a globe. Moreover, says Aristotle, "some stars are seen
in Egypt or at Cyprus, but are not seen in the countries to the north of
these; and the stars that in the north are visible while they make a
complete circuit, there undergo a setting. So that from this it is
manifest, not only that the form of the earth is round, but also that it
is part of not a very large sphere; for otherwise the difference would
not be so obvious to persons making so small a change of place.
Wherefore we may judge that _those persons who connect the region in the
neighbourhood of the Pillars of Hercules with that towards India, and
who assert that in this way the sea is_ ONE, do not assert things very
improbable."[448] It thus appears that more than eighteen centuries
before Columbus took counsel of Toscanelli, "those persons" to who