Samenvatting
The study is divided into three parts. Chapter 1 gives the derivation of the general system and number of mathematical particulars. Chapter 2 gives applications with the aid observations made in O'Neill, Nebraska (U.S.A.) in 1953 and 1956. These applications must be regarded as examples only, because the accuracy of the observations is not quite sufficient. Finally, the so-called power law is dealt with in a short third chapter.