1 The Birth of Science - MSRI

110 4. Scientific Technology
It should be stressed that modern steam engines are not at all, as is often
implicitly assumed, an invention independent of the Hellenistic engines;
there is a continuous line of descent. Heron’s expositions were studied
carefully by Leonardo da Vinci, among others. The possibility of employing
steam as a source of power was then mooted by Giambattista della
Porta in his Pneumaticorum libri tres (1601), based on Heron’s Pneumatica.
113 The first steam engine actually built in modern times seems to have
been one described in 1615 by Salomon de Caus; it operated an ornamental
fountain intermittently. Thus the inheritance from Heron was so
complete that it even concerned the end to which the machine was put.
Heronian technology hung on for another century in various hands, un- page 151
til it became economically convenient to start building steam engines for
industrial use. 114
4.8 The Antikythera Mechanism
In 1902, near the wreck of a ship that foundered by the islet of Antikythera,
between the Peloponnesus and Crete, divers found some highly corroded
bronze fragments that at first appeared to be the remnants of some clocklike
object with complicated gears. The mechanism dates from the early
first century B.C., 115 but it appeared so qualitatively different from any
known object from classical Antiquity that it gave rise to absurd speculations
of all sorts. 116
The partially readable inscriptions on the fragments make it clear that
the mechanism has to do with the motions of the sun and the moon. According
to Price’s reconstruction, it was a sort of perpetual calendar, allowing
the calculation of the phases of the moon, past and future. To this
end a gear train converted the motion of a wheel representing the solar cy-
113
Della Porta’s work was soon translated into Italian under the title I tre libri de’ spiritali (1606).
With the end of ancient science, the meaning given to pneuma by Hellenistic scientists had been
forgotten, and the word was generally translated “spiritus” or its equivalent in modern languages,
in a sense similar to the one it had had in the classical period. Reversing in this way the path
traveled by Ctesibius and Herophilus, we get the amusing result of the same adjective being used
for “spiritual” beings and steam engines.
114
Which is to say, when the rapidly growing energy needs of nascent industrialization no longer
could be met by watermills alone.
115
In 1985, Jacques Cousteau found on the shipwreck coins issued in Pergamum in 86 B.C. (see
[Casson: AM], p. 224), indicating that the wreck probably took place not long thereafter.
116
Humorously recounted in [Price: Gears], p. 12. The early date of the find is secure, among other
reasons because a paleographical study of the inscriptions shows they are contemporary with the
shipwreck. For an accurate description of the finds and a reconstruction of the whole machine, see
[Price: Gears]. The description in [Price: Instruments] was written before the author studied the
fragments in person and is completely superseded.
Revision: 1.14 Date: 2002/10/24 04:25:47