HISTORY OF THE PROBLEM
245
by actually quoting the proof and the epigram, which are the
genuine work of Eratosthenes.
Our document begins with the story that an ancient tragic
poet had represented Minos as putting up a tomb to Glaucus
but being dissatisfied with its being only 100 feet each way;
Minos was then represented as saying that it must be made
double the size, by increasing each of the dimensions in that
ratio. Naturally the poet ‘ was thought to have made a mis
take’. Yon Wilamowitz has shown that the verses which
Minos is made to say cannot have been from any play by
Aeschylus, Sophocles, or Euripides. They are the work of
some obscure poet, and the ignorance of mathematics shown
by him is the only reason why they became notorious and so
survived. The letter goes on to say that
‘Geometers took up the question and sought to find out
how one could double a given solid while keeping the same
shape; the problem took the name of “ the duplication of the
cube ” because they started from a cube and sought to double
it. For a long time all their efforts were vain; then Hippo
crates of Chios discovered for the first time that, if we can
devise a way of finding two mean proportionals in continued
proportion between two straight lines the greater of which
is double of the less, the cube will be doubled; that is, one
puzzle (a,7r6pr]/j.a) was turned by him into another not less
difficult. After a time, so goes the story, certain Delians, who
were commanded by the oracle to double a certain altar, fell
into the same quandary as before.’
At this point the versions of the story diverge somewhat.
The pseudo-Eratosthenes continues as follows:
‘ They therefore sent over to beg the geometers who were
with Plato in the Academy to find them the solution. The
latter applying themselves diligently to the problem of finding-
two mean proportionals between two given straight lines,
Archytas of Taras is said to have found them by means of
a half cylinder, and Eudoxus by means of the so-called curved
lines; but, as it turned out, all their solutions were theoretical,
and no one of them was able to give a practical construction
for ordinary use, save to a certain small extent Menaechmus,
and that with difficulty.’
Fortunately we have Eratosthenes’s own version in a quota
tion by Theon of Smyrna:
‘ Eratosthenes in his work entitled Platonicus relates that,