Complete Encyclopedia of Scales by Charles Colin. The most comprehensive practical book on scale theory available. In the key of G, but intended for all instruments, including trumpet, trombone, tuba, and French horn.

From the author's foreword:

Attention: Teachers

Present your students with exciting new scale studies. The Encyclopedia of Scales contains historical background and graphic constructions of many exotic scales. The International Scale Reference provides additional material.

Attention: Composers and Arrangers

The scales will offer many hours of interest and fresh material. New ideas in a multitude of tonalities are presented. The historical background and scale construction diagrams are useful and excellent references for school and personal use. The Encyclopedia is also a great help in developing ear training. Arabic, Chinese, Hungarian, Spanish, Japanese, and Whole Tone Scales are some of the scales presented.