1 The Birth of Science - MSRI

100 4. Scientific Technology
of Britannia) 68a and even the frozen ocean (polar pack ice). 68b Strabo scolds
Eratosthenes for using data from Pytheas, whom he considers a fibber, but
in our days the credibility of Pytheas has been confirmed not least by the
fragments transmitted by Strabo.
Trips in the Atlantic, toward the West, are mentioned by Diodorus Siculus,
Plutarch and others. 69 Strabo even talks of attempts to circumnavigate
the globe. 70
Open-sea voyages certainly employed the theoretical instruments mentioned
earlier. Did science also give sailors useful technological products?
It may not have been by chance that Pytheas, the explorer of the North
Atlantic, was a Greek from Massalia, a city recorded by Strabo as having
been famous for the manufacture of instruments useful in navigation. 71
Strabo mentions also that in Massalia and in Cyzicus, as in Rhodes, the
secrets of mechanical arts were guarded with particular care; 72 this may
help explain our lack of information on the subject.
Another area where technology was useful to navigation was in the digging
of canals. We mention here just the reactivation, around 275 B.C., of
the old canal that connected the Mediterranean with the Red Sea; 73 in the page 139
imperial age it was no longer passable 74 and it took about two thousand
years for navigation from one sea to the other to become possible again.
4.5 Naval Architecture. The Pharos
Little is known about techniques of naval architecture. We do know that
the third century B.C. witnessed radical changes in this area, including an
68a
In Pliny (Natural history, II, 186), Pytheas is made to report about Thule that days and nights
last six months; in the more reliable Cleomedes (Caelestia, I, 4, 208–231), that around the solstice the
day lasts a month. According to Diogenes Laertius (Vitae philosophorum, IV, 58), a certain Bion was
the first to claim the existence of places where day and night last six months.
68b
Strabo, Geography, I, iv, 2–3; II, iv, 1.
69
Diodorus Siculus, Bibliotheca historica, V, xix–xx; Plutarch, Vita Sertorii, viii. Diodorus talks of a
great island, many days to the west, with mountains and navigable rivers. The Carthaginians, he
reports, had founded a colony there and even considered moving there en masse if their city were
in grave danger. Many testimonia about Atlantic trips are collected and discussed in [Manfredi].
70
Strabo, Geography, I, i, 8.
71
Strabo, Geography, IV, i, 5.
72
Strabo, Geography, XIV, ii, 5.
73
The canal (of which archeological evidence still remains) joined a branch of the Nile with the
Red Sea. It may have been dug as early as the Pharaohs and reactivated already once by King
Darius of Persia. According to Strabo (Geography, XVII, i, 25) and Diodorus Siculus (Bibliotheca
historica, I, xxxiii, 9–11), who mention the Pharaoh-era and Persian precedents as failed attempts,
the canal was first placed in operation by Ptolemy II Philadelphus. But it was already known to
Herodotus (Historiae, II, 158) and is mentioned in an Iranian inscription by Darius.
74
Already Pliny does not seem to be aware that the canal ever worked, though he mentions the
attempts made to build it (Natural history, VI, 165–166).
Revision: 1.14 Date: 2002/10/24 04:25:47