Prop. VI. Pr.
To remove a given Tangent from a given Circle, and to bring another given Line into contact with it.
Let UNIV be a Large Circle, whose centre is O, (V being, of course, placed at the top,) and let WGH be a triangle, two of whose sides, WEG and WH, are in contact with the circle, while GH (called 'the base' by liberal mathematicians,) is not in contact with it. (See Fig. 1.) It is required to destroy the contact of WEG, and to bring GH into contact instead.