1 The Birth of Science - MSRI

298 11. The Age-Long Recovery
by the inability to recapture the ancient technology that had allowed the
casting of molten metal into colossi. 35
Although the methodology of science remained well beyond the grasp
of Renaissance intellectuals, there was widespread interest in certain sci- page 368
entific theories, especially those, such as mathematical geography and astronomy,
that were essential to navigation.
Already in 1406 Jacopo Angelo had translated Ptolemy’s Geography into
Latin, and later he brought a copy of the original from Constantinople
to Europe. The Geography was finally printed in 1477. To appreciate the
importance of this work it is enough to compare a map prior to that date
(apart from those made in Islamic and Iberian lands 35a ) with those that
came after: for instance the Hereford Mappa Mundi, drawn around 1300
in England and showing an oceanless world centered in Jerusalem and
crammed with unrecognizable continents separated by thin water lines,
versus the 1492 map engraved by J. Schnitzer in Ulm.
The rediscovery of mathematical geography breathed new life into an
old Hellenistic idea: reaching the Indies by sailing west. 36 Just seven years
after the Geography was published Columbus presented his plan to the
king of Portugal, and another eight years later he bravely embarked on
his enterprise.
The next milestone in mathematical geography was the recovery in the
sixteenth century of Erathostenes’ estimate for the size of the earth. This
was in all likelihood the basis for the length of the degree of the meridian
adopted during that century by Portuguese navigators. 37
At the same time that mathematical geography was being rediscovered,
so was ancient astronomy. Girolamo Fracastoro and Giovambattista Amici
proposed again, independently of one another, the theory of concentric
spheres of Eudoxus of Cnidus. The study of the classics also led to the
rediscovery of the earth’s motions: the first modern work to propose the
daily rotation was written around 1525 by the humanist Celio Calcagnini,
professor of belles-lettres at Ferrara. 37a
Aristarchus’ heliocentric theory was first revived by Copernicus in his
De revolutionibus orbium caelestium, published in 1543. That Copernicus
35
We don’t know why this technology was developed in the first place, but we can be sure that in
the third century B.C. Rhodes was no less interested in naval technology than in large ornamental
statues. See pages 100 and 102.
35a
See page 294.
36
Attempts to circumnavigate the globe are recorded in Strabo; see note 70 on page 100.
37
[Taylor], p. 547.
37a
Quod caelum stet, terra moveatur, vel de perenni motu Terrae, published posthumously in his Opera
aliquot, Basel, 1544. His arguments for proposing the earth’s rotation consist essentially of a series
of classical citations, ranging from Virgil to Archimedes.
Revision: 1.11 Date: 2003/01/06 07:48:20