Dictionary of Music - Birding America

376 Sessions, RogerNunc dimittis (or Deus misereatur); the CommunionService consists of the Decalogue (or Responses),Kyrie, Creed, Sanctus, Benedictus qui venit, AgnusDei, and Gloria in excelsis (compare the parts of theRoman Catholic Mass; see under MASS). A full serviceconsists of musical settings of all these parts,usually in the same key. Such a service is referred toby both the composer’s name and the key of themusic, for example, Purcell’s Service in B-flat.Service music has been written since the sixteenthcentury, when the Anglican Church declareditself independent of Rome. Among the notableearly composers of service music are ChristopherTye (c. 1500–c. 1572) and Thomas Tallis (c.1505–1585). The early composers distinguishedbetween a short service, a relatively simple setting,and a great service, set either in elaborate counterpointor antiphonally (with two choirs singing inturn and together). Other notable composers of servicemusic are Byrd, Thomas Tomkins (1572–1656),and Gibbons. With only a few exceptions, little servicemusic of quality was produced during the seventeenthand eighteenth centuries. Even composerssuch as Purcell and William Boyce wrote betteranthems than services. The nineteenth century sawlittle improvement, though Samuel Sebastian Wesley(1810–1876), John Stainer (1840–1901), andCharles Villiers Stanford (1852–1924) made somecontributions of note. In the twentieth century,Ralph Vaughan Williams and Benjamin Britten bothwrote some fine service items but no full services.Sessions (sesh′əns), Roger, 1896–1985. AnAmerican composer who became known as one ofthe outstanding American composers of his time,even though much of his music is quite difficult andtherefore performed relatively rarely. Among Sessions’steachers was Ernest Bloch, who had greatinfluence on his development. Sessions himselfbecame an influential teacher, and he also devotedhimself to promoting the performance of contemporaryAmerican music, through festivals and similaractivities. Sessions’s own works are largely atonal(see ATONALITY) and make considerable use ofcounterpoint. Occasionally he used serial techniques(as in his Violin Sonata and Symphony no. 3), butgenerally he drew on a large variety of forms andstyles, including the large classical forms (sonata,symphony). Sessions’s works of the 1920s are generallyneoclassic, with their emphasis on counterpoint.In the 1930s and 1940s he used more andmore chromatic harmonies, and in his later works(from the 1950s on) more and more serial elementsappeared. Besides eight symphonies, Sessions’scompositions include a Violin Concerto (composed1935, first performed 1960), the one-act opera TheTrial of Lucullus (1947), a Sonata for solo violin(1953), Piano Concerto (1956), The Idyll of Theocritus(1954) for soprano and orchestra, the opera Montezuma(composed 1941–1962), the cantata WhenLilacs Last in the Dooryard Bloom’d (composed1970, performed 1977), Concerto for Violin, Cello,and Orchestra (1971), Concerto for Orchestra(1981), three piano sonatas, and many smallerworks. His books include an important text, HarmonicPractice.set A group of musical elements, most often pitchclasses, particularly the twelve-note set of pitches ina serial composition (see SERIAL MUSIC). The termwas borrowed from mathematical set theory by MiltonBabbitt and occasionally is applied to durations,dynamic levels, and other elements subjected to serialtechniques.Webern liked using a derived set, that is, atwelve-note set derived from a smaller set by meansof inversion, retrogression, and transposition. In hisConcerto op. 24, for example, he used a group ofthree notes, B♮ B ♭ D♮ , along with its retrograde inversion(E♭ G♮ F ♯ ), its retrograde (G ♯ E ♮ F ♮ ), and its inversion(C♮ C ♯ A ♮ ) to create a new twelve-note set.Serial composers sometimes invoke combinatoriality,the relationships between different arrangementsof a set, so as to create a new series. Forexample, if the above-described set of Webern’sConcerto were divided into two six-note series(hexachords) and inverted, one might combine theoriginal set’s first hexachord with the inversion’ssecond hexachord to create a new set.Seven Last Words, The A setting of the sevenlast words spoken by Jesus while he was being crucified.Among the best-known of these works arethose by Schütz (seventeenth century), Haydn (eigh-