ELM

Dictionary of Science, Literature and Art · 1842 · p. 10

Lastly, through the points E and F let E N and F O be drawn, meeting the opposite sides of the cone in N and O. Because of the similar triangles, we have EG:GK::EF:FO, and F G: G H:: F E: E N, therefore EG-GF:GKGH::EF2: [s. 285]