Chirality in chemistry.

The useful terms chiral and chirality were coined by W. H. Thompson (Lord Kelvin) in 1884 and are derived from cheir, the Greek word for a hand, indeed one of the most familiar chiral objects. The simplest chiral object of the three-dimensional perceptual space is, however, the chiral three-dimensional simplex, the irregular tetrahedron. As early as 1827 the famous German mathematician August Ferdinand Mobius (of the Mobius-strip) pointed out that the volume of a tetrahedron, expressed as a determinant involving the Cartesian coordinates of its labelled vertices, and of its mirror image have different signs, which are not dependent on the position of the tetrahedra but change by reflection.