in geometry, a regular plain figure of 100 sides and angles. Though the imagination cannot form the idea of such a figure, yet we may have a very clear notion of it in the mind, and can easily demonstrate that the sum of all its angles is equal to 1996 right ones: for the internal angles of every plane figure are equal to twice as many right ones as the figure hath sides, except those four which are about the centre of the figure, from whence it may be resolved into as many triangles as it has sides.

The author of l'Art de Peintre, p. 44, has brought this instance to show the distinction between imagination and conceiving.

CHILLARCHA, or CHILIARCHUS, an officer in the armies of the ancients, who had the command of a thousand men.