Section 34.—ELLIPTICAL MOTION.

[604]. Ellipsograph; by gearing; the bevil wheel A is fixed, the other three revolving with the whole machine on the fixed central standard, the distance A′ should equal the difference between the major and minor axes of the ellipse.

[605]. Performs the same operation in a similar way; A is fixed; B is same diameter as A; and C = ¹⁄₂ diameter of A and B.

[606]. Common trammel or ellipsograph.

There are other forms of apparatus for drawing ellipses merely (see Knight’s Dictionary of Mechanics). See [Trammel Gear], [Sec. 40].

[607] & [608]. Two forms of ellipsographs or elliptical cranks.