The treatise, written in his middle to late 20s, established Heinichen as a major music theorist in elite music circles. It is the first German treatise on basso continuo accompaniment from a bass with or without figures, and the first to draw important distinctions between the stylus gravis and stylus theatralis. Perhaps most significant is its inclusion of what he called the musical circle and is now known as the circle of fifths, and for the first time describing it as being characterized by the major-minor dichotomy of today. This first full translation from the German was inspired by the historical performance movement, and is intended to be of interest to performers as well as to musicologists and music historians. It is not indexed. Annotation ©2013 Book News, Inc., Portland, OR (booknews.com)