Very dilute solutions of diphenylmercury in carbon tetrachloride have been found not to have orientation polarization, but in not-so-dilute carbon tetrachloride or in dioxane and benzene at any concentration there is evidence of moment. Moreover, these moments vary negatively in carbon tetrachloride and dioxane and positively in benzene with respect to temperature. The angular C—Hg—C linkage responsible for orientation polarization is also demonstrated by appreciable moments for para methylmercuri-bis-benzene and the homologous durene. Magnitudes comparable with the aryl analogues are found for several alkyl-bis-mercurials, but the similarity in the moments of trifluoromethyl and methyl-bis-mercury as well as a temperature coefficient for moment of the latter compound indicates that the C—Hg—C linkage may vary widely and easily. However, a lower limit may be set by the moments of mercuracyclohexane and mercuracycloheptane in which the mercury angle is fixed by the cyclic structure.