the lunar theory considerably, and discovered minor inequalities which
could be allowed for by the addition of new epicycles. We may look
upon these epicycles of Apollonius, and the excentric of Hipparchus,
as the responses of these astronomers to the demand of Plato for
uniform circular motions. Their use became more and more confirmed,
until the seventeenth century, when the accurate observations of Tycho
Brahe enabled Kepler to abolish these purely geometrical makeshifts,
and to substitute a system in which the sun became physically its
controller.


FOOTNOTES:

[1] _Phil. Mag_., vol. xxiv., pp. 481-4.

[2]

Plaeiadas t' esoronte kai ophe duonta bootaen
'Arkton th' aen kai amaxan epiklaesin kaleousin,
'Ae t' autou strephetai kai t' Oriona dokeuei,
Oin d'ammoros esti loetron Okeanoio.

"The Pleiades and Bootes that setteth late, and the Bear,
which they likewise call the Wain, which turneth ever in one
place, and keepeth watch upon Orion, and alone hath no part in
the baths of the ocean."

[3] See Pearson in the Camb. Phil. Soc. Proc., vol. iv., pt. ii., p.
93, on whose authority the above statements are made.