Report discussing a search conducted for stable, oil-soluble, organic compounds of metals (and other elements) for use in the spectrographic analysis of petroleum products. Compounds having suitable physical properties have been selected as standards. Methods are given for preparation of the compounds and for the spectrographic and chemical analysis of the chosen standards. Procedures are described for the preparation of stable solutions thereof in petroleum oils.

Report discussing the VLF, ELF propagation in the earth-ionosphere waveguide emphasizing the total field found by summing all modes which contribute appreciably. Solutions are given and calculations are made for a homogeneous isotropic ionosphere, a homogeneous ionosphere with a constant radial magnetic field imposed, and an ionosphere with a magnetic field of arbitrary dip angle.

Report issued by the Bureau of Standards over new developments of electrical resistivity in manganin wire coils. The results of the developments are discussed. This report includes tables, illustrations, and photographs.