Journal of Statistical Physics, Vol. 34, Nos. 5/6, 1984. p. 883-893.
The following topics are reviewed briefly: (i) The first experimental determination of the decrease in the smectic A-nematic transition temperature brought about by a twist deformation, an effect which is the analog of the influence of a magnetic field on the superconductor-normal metal transition; (ii) the similarity between the hydrodynamics of cholesteric liquid crystals and superfluid hydrodynamics, and some of its consequences, e.g., the possibility of a temperature wave attending second sound in the cholesteric phase; and (iii) the nematic-
smectic A-smectic C multicritical point.