X^HI
MENSURATION: HERON OF ALEXANDRIA
Controversies as to Heron’s date.
The vexed question of Heron’s date has perhaps called
forth as much discussion as any doubtful point in the history
of mathematics. In the early stages of the controversy much
was made of the supposed relation of Heron to Ctesibius.
The Belopoe'ica of Heron has, in the' best manuscript, the
heading "Hpcovos Ktijctl^lov BeXonouKa, and from this, coupled
with an expression used by an anonymous Byzantine writer
of the tenth century, o A&Kprjubs KrrjcrifSLos o rov AXe£avSpecos
"Hpcovos KaQ-qypTrjs, 1 Ctesibius of Ascra, the teacher of Heron
of Alexandria ’, it was inferred that Heron was a pupil of
Ctesibius, The question then was, when did Ctesibius live'?
Martin took him to be a certain barber of that name who
lived in the time of Ptolemy Euergetes II, that is, Ptolemy VII,
called Physcon (died 117 b.c.), and who is said to have made
an improved water-organ 1 ; Martin therefore placed Heron at
the beginning of the first century (say 126-50) b.c. But
Philon of Byzantium, who repeatedly mentions Ctesibius by
name, says that the first mechanicians {Teyvlrou) had the
great advantage of being under kings who loved fame and
supported the arts. 2 This description applies much better
to Ptolemy II Philadelphus (285-247) and Ptolemy III Euer
getes I (247-222). It is more probable, therefore, that Ctesibius
was the mechanician Ctesibius who is mentioned by Athenaeus
as having made an elegant drinking-horn in the time of
Ptolemy Philadelphus 3 ; a pupil then of Ctesibius would
probably belong to the end of the third and the beginning of
the second century b.c. But in truth we cannot safely con
clude that Heron was an immediate pupil of Ctesibius. The
Byzantine writer probably only inferred this from the title
1 Athenaeus, Deipno-Soph. iv. c. 75, p. 174 b-e: cf. Vitruvius, x. 9, 13.
2 Philon, Meehan. Synt., p. 50. 38, ed. Schone.
3 Athenaeus, xi. c. 97, p. 497 b-e.