Holditch Curves inside an Ellipse

move chord

6.3

chord length

1.77

chord divider

0.5

hide chord

ellipse shape

eccentricity:

0.581

Around 1858, the Reverend Hamnet Holditch studied the curves generated by a point on a chord of fixed length sliding inside another curve.

This Demonstration is an animation showing the generation of some Holditch curves inside ellipses of different eccentricities. You can see the effect of the chord length and the position of the generating point on the chord.