This journal provides immediate access to some articles. Volume 9(9); September 1923 Astronomy The Asymmetry in the Distribution of Stellar Velocities PMCID: PMC1085410 On the Mean Absolute Magnitudes of the K and M Giants and the Systematic Errors in Trigonometric Parallaxes PMCID: PMC1085411 Chemistry A Theory of Color Production: I PMCID: PMC1085408 A Theory of Color Production: II, Inorganic Compounds PMCID: PMC1085409 Mathematics Groups of Order 2m in Which the Number of the Sub-Groups of at Least One Order Is of the Form 1 + 4k PMCID: PMC1085413 Physics The Motion of a Falling Chronograph Projectile PMCID: PMC1085414 Psychology Measurements on the Expression of Emotion in Music PMCID: PMC1085412 Journal Matter Original table of contents page Administrative content — journal masthead, notices, indexes, etc. | ||