1 The Birth of Science - MSRI

10
Lost Science
Besides being just a small part of the whole, the Hellenistic scientific writings
that have come down to us were often altered in intervening centuries
by editors who adapted them to their own notions. In this chapter we will
try to reconstruct certain ideas of Hellenistic science, sometimes through
plausible conjecture and sometimes in a less tentative way. Our evidence
will include indirect testimonia present in literary works that are not often
regarded as source material for history of science studies; in passing, it
may be said that our knowledge of ancient science might increase considerably
if the fragments and testimonia on various scientific theories were
systematically collected.
10.1 Eratosthenes’ Measurement of the Meridian
Eratosthenes, with the method discussed in Section 3.2, obtained the value
252,000 stadia as the earth’s circumference along a meridian. Estimating
the accuracy of this measurement is not easy: there has been controversy
on the value of a stadium in this context. The most likely reconstruction
puts Eratosthenes’ stadium in the range 155–160 m, 1 implying an error of
1 A value of 157.5 m for the stadium used by Eratosthenes was determined by Hultsch in his
thorough investigation of Greek measurements ([Hultsch: GRM], p. 61). Although different from
the traditional value used in Greece, it has been accepted by most subsequent scholars as substantially
correct. The argument is based primarily on a passage of Pliny (Naturalis historia, XII, 53),
where the ratio between the stadium and the schoenus is reported to have two alternative values,
one of them being called “Eratosthenes’ ratio” (Eratosthenis ratione). For the view that Eratosthenes
used the traditional stadium, of about 185 m, see [Rawlins: ESNM].
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