An improved, though still relative, quantitative expression has been derived for the electrical anisotropy E. A. The E. A. is a linear function of the elongation up to a certain limit, as is also the optical birefringence. The relation of electrical to optical anisotropy has been studied in greater detail. A more critical discussion in terms of atomic model structures is given of the hypothesis that E. A. in the compounds studied is due to the formation of continuous parallel chains of hydrogen bridges, having electronically conducting character: The materials studied were: polyvinyl acetate and its hydrolyzed stages down to polyvinyl alcohol, cellulose acetate and its hydrolyzed stages down to (hydrate) cellulose.
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