New measurements have been made of the refractivities a t 20°, and the parachors of aliphatic aldoximes, ketoximes, and ketoxime O-alkyl ethers, NN-dialkylhydrazines, aliphatic ketazines, p-mono-and F-di-alkylaminopropionitriles, P-alkoxypropionitriles, dialkyl azodiformates and dialkyl carbonates, and the contributions of the :N*OH, :NO, N-NH,, :N-N:, NH, N (tertiary), N:N, and CO, groups, and of 0 (from alkoxypropionitriles) have been evaluated. The bond refractions, as well as the bond parachors and the bond-refraction coefficients, have been computed for a large number of links with the aid of the experimental data given in this and previous papers of this series. The bond constants of several links have been deduced by a number of independent methods, and the results are in satisfactory agreement. The comprehensive table of bond refractions and bond parachors may be employed for the computation of " theoretical " refractions and parachors. The bond-refraction coefficients permit of the calculation of the refractive index (nio) of a liquid compound from its chemical formula.The structures of the esters of oxy-acids and of related compounds are discussed.THE determination of atomic, group, and structural parachors and refractivities has been extended to a number of series of nitrogen-containing compounds (compare Eisenlohr, 2. physikal. Chem., 1912,79,412). New measurements of the densities and surface tensions over a range of temperatures as well as the refractive indices at 20" for the c, D, F, and G' lines have been made and the constants calculated as in previous papers of this series. TABLE 1. Values for the :N*OH group from aldoximes artd ketoxiines.