Abstract
Even to-day the theory of sorption phenomena does not provide for an exact analytical solution to the problem of the different types of binding existing between the liquid and gaseous phases and the material to be studied. Under these circumstances, the empirical relations between the equilibrium moisture content and the relative air humidity is of increasing significance. The validity of the mathematic principles of the Theory BET and of the Equation of Henderson is examined by comparison with experimental results obtained for tobacco. The limits set to determination reveal themselves even in the sphere of adsorption, if the calculation of the Theory BET is made on the basis of five molecular layers. Finally, the sorption theory which has recently been established by Kollmann and which is based on statistical investigations is presented. The author intends to apply Kollmann's theory to tobacco and will report the results at a later date