He first appeared at the Royal Opera House, Covent Garden in 1914 conducting Richard Wagner's "Tristan und Isolde". He was a man with a lot of energy, and he introduced the audiences to a lot of music they had not heard, especially by Russian composers such as Alexander Scriabin, but also English music by Ralph Vaughan Williams, Arnold Bax and Gustav Holst, whose suite "The Planets" he gave the first complete London public performance.