The aim of this specially elaborated book of music theory has been to create, define, systematize and analyse all the possible scales in the twelve-tone equal temperament system. It consists of three parts: the first and longest part lists thousands of scales marked with numbers, the second displays a table with all the modes of the scales, the third contains all the possible occurrence of chords in every tonal system. The volume with its high professional value and fine appearance is recommended to musicians who are interested in new theories and are not alien to mathematics.