iv 
CONTENTS 
Positive Ray Analysis of Magnesium By A. J. Dempster 45 
The Energy Content of the Diapason By C. Barus 47 
The Peltier Effect By E. H. Hall 62 
The Open Mercury Manometer Read by Displacement Interferometry 
By C. Barus 71 
Thermo-Electro Action and Thermal Conduction in Metals: A Summary 
By E. H. Hall 98 
Note on a Method of Determining the Distribution of Pore Sizes in a 
Porous Material By E. W. Washburn 115 
The Diffusion of Air through Water in the Lapse of Years 
By Carl Barus 133 
The Destruction of Phosphorescent Zinc Sulfides by Ultra Violet Light 
By Leonard B. Loeb and, Lloyd Schmiedeskamp 202 
Acoustic Pressure Distributions, Chiefly in Reservoirs and Pipes 
By Carl Barus 207 
An Apparatus for Determination of the Gases in Blood and Other Solu- 
tions By Donald D. Van Slyke 229 
A Remeasurement of the Radiation Constant, h, by Means of X-Rays 
By William Duane, H. H. Palmer, and Chi-Sun Yeh 237 
The U-Tube Absolute Electrometer By Carl Barus 242 
On the Calculation of the X-Ray Absorption Frequencies of the Chemical 
Elements By William Duane 260 
On the Calculation of the X-Ray Absorption Frequencies of the Chemical 
Elements (Second Note) By W. Duane 267 
The Evaluation of Quantum Integrals .By E. C. Kemble 283 
The Further Extension of the Ultra-violet Spectrum and the Progression 
with Atomic Number of the Spectra of Light Elements. By R.A. Millikan 289 
Measurements of the Deviation from Ohm's Law in Metals at High Current 
Densities By P. W. Bridgman 29& 
The Mobilities of Electrons By L. B. Loeb 307 
The Growth and Decay of Photo-Thermionic Currents from Oxide Coated 
Filaments By H. D. Arnold and Herbert E. Ives 323 
CHEMISTRY 
Experiments on the Electrical Conduction of a Hydrogen Alloy 
By D. P. Smith 28 
The Correlation of Compound. Ionization and Solubility in Solutions. 
Outline of a Modified Ionization Theory By J. Kendall 56 
Studies on Catalysis I. The Reduction of Uracil to Hydrouracil 
By T. B. Johnson and E. B. Brown 75 
The Application of a Differential Thermometer in Ebullioscopy 
By A. W. C. Menzies and S. L. Wright 77 
A Differential Thermometer By A. W. C. Menzies 81 
The Effect of Temperature and of the Concentration of Hydrogen Ions 
upon the Rate of Destruction of Antiscorbutic Vitamin (Vitamin C) 
By H. C. Sherman, V. K. LaMer and H. L. Campbell 279 
GEOLOGY AND PALEONTOLOGY 
Some Geologic Conclusions from Geodetic Data By W. Bowie 23 
Origin and History of the Bear Family in the Western Hemisphere with 
Particular Reference to the Relation of This Question to Problems 
of Geographical History By John C. Merriam 183 
