THE COLLECTION
359
sizes and distances of the sun and moon), Autolycus (On the
moving sphere), Carpus of Antioch (who is quoted as having
said that Archimedes wrote only one mechanical book, that
on sphere-making, since he held the mechanical appliances
which made him famous to be nevertheless unworthy of
written description: Carpus himself, who was known as
mechanicus, applied geometry to other arts of this practical
kind), Charmandrus (who added three simple and obvious loci
to those which formed the beginning of the Plane Loci of
Apollonius), Conon of Samos, the friend of Archimedes (cited
as the propounder of a theorem about the spiral in a plane
which Archimedes proved: this would, however, seem to be
a mistake, as Archimedes says at the beginning of his treatise
that he sent certain theorems, without proofs, to Conon, who
would certainly have proved them had he lived), Demetrius of
Alexandria (mentioned as the author of a work called ‘ Linear
considerations ’, ypappuKal enLaTcccreis, i.e. considerations on
curves, as to which nothing more is known), Dinostratus,
the brother of Menaechmus (cited, with Nicornedes, as having
used the curve of Hippias, to which they gave the name of
quadratrix, Terpaycovi^ovcra, for the squaring of the circle),
Diodorus (mentioned as the author of an Ancdemma), Erato
sthenes (whose mean-finder, an appliance for finding two or
any number of geometric means, is described, and who is
further mentioned as the author of two Books ‘ On means *
and of a work entitled ‘ Loci with reference to means ’),
Erycinus (from whose Paradoxa are quoted various problems
seeming at first sight to be inconsistent with Eucl. I. 21, it
being shown that straight lines can be drawn from two points
on the base of a triangle to a point within the triangle which
are together greater than the other two sides, provided that the
points in the base may be points other than the extremities),
Euclid, Geminus the mathematician (from whom is cited a
remark on Archimedes contained in his book ‘ On the classifica
tion of the mathematical sciences ’, see above, p. 223), Heraclitus
(from whom Pappus quotes an elegant solution of a vevcrts
with reference to a square), Hermodorus (Pappus’s son, to
whom he dedicated Books VII, VIII of his Collection), Heron
of Alexandria (whose mechanical works are extensively quoted
from), Hierius the philosopher (a contemporary of Pappus,