This journal provides immediate access to some articles. Volume 11(8); August 1925 Biology The Soil Population PMCID: PMC1086080 Chemistry The Paramagnetism of “Odd Molecules” PMCID: PMC1086076 The Activation of Hydrogén by Excited Mercury Atoms PMCID: PMC1086077 What Is Humus? PMCID: PMC1086078 Mathematics Concerning the Separation of Point Sets by Curves PMCID: PMC1086079 Physics An Experimental Determination of the Critical Excitation Frequency for the Production of Fluorescent X-Radiation PMCID: PMC1086083 The Calculation of the X-Ray Diffracting Power at Points in a Crystal PMCID: PMC1086084 The Effect of Commutation of Impedances on the Acoustic Pressure Produced by Paired Telephonic Systems PMCID: PMC1086085 A Statistical Quantum Theory of Regular Reflection and Refraction PMCID: PMC1086086 The Distribution of Diffracting Power in Sodium Chloride PMCID: PMC1086087 The Distribution of Diffracting Power in Certain Crystals PMCID: PMC1086088 Ionization Produced in Gaseous Reactions PMCID: PMC1086089 Ionization of Mercury Vapor by Ultra-Violet Light PMCID: PMC1086090 Modified and Unmodified Scattering Coefficients of X-Rays in Matter PMCID: PMC1086091 The Energy Reappearing as Characteristic X-Rays when X-Rays Are Absorbed in Copper PMCID: PMC1086092 Physiology The Precipitin Reaction of Thyroglobulin: Specificness; Presence of Thyroglobulin in Human Thyroid Veins; Production by Rabbit of Precipitin for Rabbit Thyroglobulin; Thyroglobulin in the Foetal Thyroid and in Exophthalmic Goiter PMCID: PMC1086081 The Internal Secretion of the Parathyroid Glands PMCID: PMC1086082 Statistics The Logistic or Autocatalytic Grid PMCID: PMC1086075 Journal Matter Original table of contents page Administrative content — journal masthead, notices, indexes, etc. | ||