Among many aspects of a sound, its loudness and noisiness are capable of numerical scaling. An experiment has been carried out with untrained listeners which may lead to a scale of unpleasantness. It has been shown that consistent rank-ordering is possible and that there is a large measure of agreement between individuals. Comparison with the scales of loudness and noisiness show that unpleasantness is not directly related to these measures.

The phase transition temperature in pyrene and phenanthrene crystals has been measured by a polarization modulation method, which enables one to detect the variation in the refractive index in the transparent region of a crystal. The phase transition occurs at 120 K in pyrene and between 210 and 260 K in phenanthrene.