To describe the contents of a musical work is always a difficult task; and it cannot be denied that a great deal of nonsense has been written, in the endeavour to analyze, describe, and annotate the works of great musical composers. No author has had to suffer more from the indiscreet zeal of busy shallow annotators than Ludwig van Beethoven no other composer's works have been so unwarrantably and unnecessarily overladen with weak description. The small work, Beethoven's clavier-sonatm fiir ezmde' der Tonkzmst erléiutert z'on Ems! Van Elm lein, stands forth as an honourable exception amidst the host of insipid commentaries on the great master's works — the multitudinous explanations that explain nothing. Elterlein's book appeared in Leipsic, in I856. It has, since that'year, gone through many editions, and has obtained great and deserved popularity in Germany. Although Herr von Elterlein is a musical amateur, he writes with the ripe knowledge and thorough understanding of a practical musician; and as the merits of his book speak for themselves, any further praise would be super?uous.