Illustration showing the definition of an ellipse. "An ellipse is a curve which is the locus of a point…

Illustration showing how a hyperbola con be constructed by points, having been given the foci and the…

Illustration showing the definition of an hyperbola. "An hyperbola may be described by the continuous…

"Any rod, or bar, which is used in raising a weight, or surmounting a resistance, by being placed on…