 The Langmuir-Wrinch hypothesis of hydrophobic stabilization shared in the downfall of the cyclol model, owing mainly to the influence of Linus Pauling, who favored the hypothesis that protein structure was stabilized by hydrogen bonds.Another twenty years had to pass before hydrophobic interactions were recognized as the chief driving force in protein folding.In her third paper on cyclols (1936), Wrinch noted that many "physiologically active" substances such as steroids are composed of fused hexagonal rings of carbon atoms and, thus, might be sterically complementary to the face of cyclol molecules without the amino-acid side chains.