ABSTRACT
When I was asked by the publishers to enlarge and revise the Treatise on Instrumentation by Hector Berlioz, I thought at first that the masterwork of the great Frenchman did not need such help to be even today a source of enjoyment and stimulation for all musicians. It appeared to me complete in itself and full of ingenious visions, whose realization by Richard Wagner is obvious to every connoisseur.
