From Zappa Wiki Jawaka
Cecil Forsyth (1870-1941) is name-checked (misspelled "Forsythe") on the cover of "Freak Out!" (1966) under the heading "These People Have Contributed Materially In Many Ways To Make Our Music What It Is. Please Do Not Hold It Against Them".
A British musicologist, wrote one of THE books on orchestration, called... "Orchestration" (it was first published in 1914; the second edition dates from 1935, and was reprinted in 1982). It's a comprehensive look at orchestration with a historical and practical perspective, detailing the playing techniques and idioms of some 57 different orchestral instruments. In the New Grove Dictionary of Music and Musicians, it is marked as "for its time the most comprehensive treatment of the subject". "I have not ever found a subsequent orchestration manual to be anywhere near its equal", William Bolcom (pianist / composer / teacher) wrote in the introduction. So let's conclude that it's a the must have book on orchestrating...