bm

Updated: June 28, 2025

Let Ap represent progeny who belong to class A, and similarly Bp, Cp, Dp. Law 2 may now be set down as under Af + Bm Am + Bf Cf + Dm Cm + Df Dp Cp Bp Ap The first law holds good with the progeny of these combinations, i.e., Dp can only marry one of class C though neither the father nor mother of Dp could marry into class C; similarly for Cp, &c.

David Wynford Carnegie - Spinifex and Sand

Let LED be the spheroid touched by the line BM at the point B, and also by the planes parallel to this line at the points O and A. It is required to demonstrate that the points B, O, and A are in one and the same Ellipse made in the spheroid by a plane which passes through its centre.

Christiaan Huygens - Treatise on Light