I. Perspectives on the Mechanism of Osmosis and Imbibition.- I. The Founders.- Van’t Hoff’s Solute-Gas Analog.- Van’t Hoff on the Mechanism of Osmosis.- II. Thermodynamic Laissez Faire.- III. Some Fundamental Experimental Facts.- 1. Lowered Vapor Pressure Over Solutions and Unsaturated Gels.- 2. Osmosis by Bulk Flow.- 3. Equivalence of Hydraulic and Osmotic Flux.- 4. Osmotic Flux Moving against the Water Potential.- IV. Water Tension Theory.- Physical Models of Imbibition and Osmosis.- Cohesiveness of Water.- A. Matrices.- Measurements of Tension and the Role of the Free Surface.- Gravitational Pressure Gradients.- Negative Pressure by Crowding and Conformational Changes.- B. Matrix-Solute Balance.- Sap Rising in Trees and Vines.- Sap Tension by Rate of Filtration..- Gravitational Pressure Gradients in the Xylem 2.- At Last: Measuring Negative Sap Pressure.- Negative Solvent Pressure in Xylem and Cells.- Pressure Profiles through an Osmotic Model System.- C. Solutions and the Role of the Boundary.- Solvent Tension and the Curved Surface.- The Kelvin-Poynting Gravitational Column.- Hulett and the Solvent Tension Theory.- Epilog I: The Tortuous Way of Finding out.- Brownian Motion and Jean Perrin: Solute and Solvent as Independent Kinetic Units.- Epilog II: The Chemical Versus the Physical Mind.- Further Theoretical Support for Solute-Solvent Coupling at the Free Surface.- Other Applications of the Kelvin-Poynting Column.- D. Non Equilibrium States and the Role of Drag.- Layering Water on the Surface of a Solution.- Hydrostatic Pressures in Stirred Suspensions.- E. Where is the Site of Coupling between Solute and Solvent?.- Effect of Crowding on Osmotic Pressure.- Effect of Gravity on Osmotic Pressure.- Magnetoosmosis.- F. Answers to Part III.- V. Water Concentration Theory.- Pressure Drop at the Pore Openings.- Osmotic Flow against the Water Potential.- Anti-Gravity Devices in Trees.- Comments.- Concluding Remarks.- II. Some Reversible Thermodynamic Relationships at Equilibrium.- Some Basic Thermodynamic Statements.- The Poynting Relation.- The Clapeyron Equation.- Application of Thermodynamic Statements to Solutions.- Ideal Solution.- Interpreting the Change in Chemical Potential of a Solvent Homogeneous in a Solution.- III. Toward Understanding the Colligative Properties of a Solution.- I. Osmotic Pressure.- Distribution of Vapor Molecules in a Gravity Field.- Thermal Pressure of the Solute and Solvent Molecules within the Solution.- Induction of Enhanced Tension in the Solvent of a Solution.- Distribution of Solute Molecules within a Solution in a Gravity Field.- The Weight of the Column Below the Surface of the Solution and its Correlation with the Concentration at the Free Surface and the Osmotic Pressure of the Solution.- Vapor Pressure of a Distensible Liquid under Tension.- Summary of the Conditions which Describe the Solution in a Gravity Osmometer shown in Figs. 52 and 53.- The Greater Tension in the Solvent within a Solution Alters its Osmotic Pressure with Respect to Pure Solvent.- Height of Solution Column in a Cylindrical Gravity Osmometer.- II. Vapor Pressure.- III. Melting Point.- IV. Boiling Point.- Experimental Confirmation of Relationship between Osmotic Pressure and Lowering of Vapor Pressure.- IV. The Chemical Potential of Water.- In a Solution.- In a Matrix.- Chemical Potential of Solvent in Real Solutions.- Glossary of Terms.- References.
