In 1889 Reinitzer,1working with cholesteryl benzoate, discovered a state of matter that was later ter med cholesteric liquid crystals. It is doubtful whether the discovery of liquied crystals would have been made at that time if the optical properties of the cholesteric phase were less pronounced. Like other liquid crystals, matericals in this state act as birefringent fluids. however, at that point the resemblance endns. The optical properties may be summarized as follows:2