Construction Of A Parabola
An illustration showing how to construct a parabola by plotting. "Having given the axis, vertex, and focus of the parabola. Divide the transverse axis into any desired number of parts 1, 2, 3, etc., and draw ordinates through the divisions; take the distance A1, and set it off on the 1st ordinate from the focus f to a, so that A1 = fa. Repeat the same operation with the other ordinates - that is, set off the distance A5 from f to e, so that A5 = fe; and so the parabola is constructed."
Albert A. Hopkins Scientific America: Handy Book Of Facts And Formulas (New York: Munn & Co., Inc., 1918) 37
Courtesy the private collection of Roy Winkelman