In the selection of Illustrative passages the author has been guided by the desire to render his work useful, as far as possible, to those who might have in their libraries other treatises on Instrumentation. He has therefore endeavoured to avoid quoting extracts already given by Berlioz and other authors and he has in every instance selected examples from scores in his own library, and not from other instruction-books, for the purposes of illustration. It has always appeared to him a curious thing that although Mendelssohn is, from the purity and fine taste displayed in his instrumentation, one of the best possible models for the young composer, hardly any of the treatises previously published contain so much as one illustration taken from his works. His scores have therefore been somewhat freely drawn upon for the present volume. The author's general plan has been to quote from works less accessible to the student, rather than from those which he could easily procure for himself. It would be dishonest not to acknowledge the many valuable hints which the author has Obtained from the treatises of Gevaert and Lobe — two of the best works on Instrumentation ever written. Those who have a knowledge Of the French and German languages are strongly advised to consult these books for themselves. They will find there much useful information conveyed in a singularly clear and interesting form. In Spite Of the care which has been expended on the present book, the author dares not ?atter himself that no important inaccuracies or omissions will be found in it. It is indeed almost inevitable that, in a work containing such a multiplicity Of details, errors will creep in.