To write a handbook of methods is surely to invite criticism, as has already been said several times. On the other hand, there is a great need for methodological manuals in all fields of science. It was therefore decided to compile this book, written in good faith to help scientists, teachers and students who will, it is hoped, use it and judge it good. To be useful to the reader, such a manual must provide a broad review of the methods available and describe them in sufficient detail to permit preliminary selection and judgement. It has to give - at least for selected methods - a suffi ciently detailed description of the equipment and procedure as to be to some extent self-contained. It must assume a critical standpoint as regards the theoretical basis of the methods, the significance of results, and their errors and limitations. It must also furnish examples, pertinent numerical tables, and very complete references. All this and much more is expected of a good manual of methods.

Inhalt
1 Water in Cells and Tissues.- 1.1 Introduction and Terminology.- 1.2 Units of Water Potential and Examples of Absolute Values of Water Potential and its Components.- 1.3 The Determination of Water Potential (?w) of Cells and Tissues.- 1.4 Determination of Osmotic Potential.- 1.5 Determination of Turgor Pressure (Pressure Potential).- 1.6 Matric Potential, Bound, Free and Mobile Water.- 2 Water Content.- 2.1 Direct Methods of Water Content.- 2.2 Indirect Methods of Water Content.- 2.3 Determination of the Water Content of Cell.- 2.4 Root Bridge Method.- 2.5 Water Saturation Deficit (Relative Water Content.- 3 Water Exchange between Plant Roots and Soil.- 3.1 Availability of Soil Water.- 3.2 Determination of the Water Potential of.- 3.3 Determination of Water Absorption by.- 3.4 Xylem Sap Exudation from Excised Roots and Root Systems.- 4 Liquid Water Movement in Plants.- 4.1 Determination of Hydraulic Conductivity (Water Permeability) of Cytoplasm, Cell Membrane and Parenchymatous Tissues.- 4.2 Measurements of the Velocity of Water Movement in Xylem.- 4.3 Measurements of the Volume Flux of Water in Xylem Vessels.- 5 Water Exchange between Plant and Atmosphere.- 5.1 Introduction.- 5.2 Air Humidity.- 5.3 Water Absorption by Aerial Parts of Plants.- 5.4 Ecological Factors in Transpiration.- 5.5 Transpiration.- 5.6 Stomata.- 5.7 Guttation.- 6 Table Appendix.- 6.1 Pertinent Physical Values, their Symbols and Units.- 6.2 Prefixes for Units.- 6.3 Some Mathematical Symbols.- 6.4 Some Physical Properties of Liquid Water.- 6.5 Some Physical Properties of Water Vapour.- 6.6 Absolute Air Humidity at Various Relative Air Humidities and Air Temperatures [Range -10 to 40°C and 10 to 100% r. h.].- 6.7 Absolute Air Humidity at Various Relative Air Humidities and AirTemperatures [Detailed Tables, Range 15 to 30°C and 40 to 100% r.h.].- 7 References.- Author Index.