Ellipses and ovals: two curves so close and so far

Abstract

In this work we will deal with ellipses and ovals, comparing them both from the geometric point of view and from the one of applications. There is a notable similarity between these curves so often it’s not possible to recognize which of the two figures is, unless we consider other elements to distinguish them. We will show the presence of both curves in architectural works and in treatises, motivating their use, when it’s possible, with geometric and technological considerations.

Keywords

• conics, regular curves, normals, vaults, pointed arches, curvature.