The lecture was given on April 21, 1980. The problem with which this investigation is concerned is that of gathering information on the composer Johann Hummel, the performer Anton Weidinger, the keyed trumpet, for which the concerto was written, the concerto itself, and its ornaments, and in determining the correct performance practices of the ornaments. Sources written in the middle to late eighteenth century and from the first third of the nineteenth century gave valuable insight into the facts and attitudes concerning the composer, the performer, the instrument, and the concerto in question. Other information came from present day authorities writing in texts, periodicals, and reference works.