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“On a Poet’s Lips I Slept”
Movement 1 of Britten’s “Nocturne” for tenor and chamber orchestra
The first movement of Benjamin Britten’s “Nocturne”, set to Shelly’s exquisite text from his Prometheus Unbound, carries the keys that unite and bring understanding the rest of the work, allowing the great denouement in the last movement to arrive with all its power. In a faint whisper, the muted first violins in divisi introduce the “breathing sleeper” motive of an eighth and a sixteenth note alternating in triple time. This is a device that Britten has used previously in at least two other works to indicate an aesthetic of sleep: First simply as a rhythmic device in his “Nocturne” from On this Island (Ex. 1),
and later as a complete rhythmic-harmonic motive in the Serenade-reject song “Now sleeps the crimson petal.” (Ex. 2)
Though the tempo may place it a bit too fast for reality, the rhythm, regularity, and tension/release nature of this figure represent well the calm, even breaths of the sleeper. An up-bow indication on the long note assures that the “respiration” has a very “breathy” inception while the down-bow gives a slightly thrust “exhalation.”
In Nocturne, the “breathing” figure first presents itself high up above the staff with a long E, joined below by a long G and filled in the middle by a short B and C: clearly a CM tonality, though the defining root and 7th of the chord are ambiguously deemphasized. (Ex. 3)
Soon the violas enter in with the same chord formation but dropped down a minor third, which has the immediate consequence of redefining the tonal structure as a C6 add 6 chord, reinforced by the C on which the voice then enters. (Ex. 4)
But Britten now begins to re-obscure the tonality by layering in our tonal “breathing” chord in descending whole steps: C6 add 6, B flat 6 add 6, A flat 6 add 6, G flat 6 add 6. (see Ex. 4) Or is it a , g , f , e ? By the time the last chord is reached the voice is on E flat, seeming to reinforce the enharmonic minor seventh interpretations of these chords. (Ex. 5a)
The next phrase does nearly the same thing, this time shifted up a whole step starting on D M . (Ex. 5b) This layering of the tonally ambiguous “breathing” motive paints a fascinating scene of a swirling ethereal musical genesis, or pool of primordial tonal soup. The voice seems to come and go with whichever of the many present simultaneous tonalities it pleases to jump upon and ride for a time. After beginning to continue the same chord progression a third time, this time another whole step up on E major, (see Ex. 4) recognizable triadic tonality begins to break down into clusters creating a thick (but not sinister) haze that swirls about and rises up to the top of the staff where it dissolves into a virtual recapitulation of the opening progression, this time sticking on the C major tonality as it heads into the long vocal melisma.
The tonally ambiguous and often chromatic nature of the “breathing” motive is a method Britten typically uses in his works to indicate distance from the real and natural world. By layering and altering the tonal “breathing” figuration, Britten creates a gossamer web of drowsiness that strings from movement to movement in Nocturne, unifying the work and reminding us that through and in spite of all that happens, the protagonist is still safe asleep in his bed. His steady, even breathing sets the baseline of reality to which the work can always return from its sorties. No matter what dreams or nightmares may come, a simple return to the motive reminds us that none of it is real.
The tonal aspects of this movement are indeed interesting, but the real meaning comes from the text. The opening three lines identify the setting of the entire work:
On a poet’s lips I slept
Dreaming like a love-adept
In the sound his breathing kept;
We are entering here the world of the sleeping poet, the “love-adept.” An “adept” was traditionally an “alchemist who has attained the knowledge of how to change base metals into gold.” Of this master-thaumaturge, the text says:
Nor seeks nor finds he mortal blisses,
But feeds on the aërial kisses
Of shapes that haunt thought’s wildernesses.
He will watch from dawn to gloom
The lake-reflected sun illume
The yellow bees in the ivy-bloom,
Nor heed nor see what things they be;
But from these create he can
Forms more real than living man,
Nurslings of immortality!
This sleeper-poet is the master alchemist because from the ordinary things of nature and life he can create life immortal, and the secret agent he has discovered to enact such a change appears to be sleep itself.
Britten memorializes this idea by encapsulating it in a magical phrase. (Ex. 6a)
Most of its rhythm is a palindrome (Ex. 6b),
a form that has been used since antiquity for intellectual puzzles and wordplay. In addition, the phrase transforms our opening CM7 sleeping motive at the word “immortality” into E flat major, a key often used by Britten to indicate deity or immortality. The tonality then conjures back and forth until it lands on D flat. The importance of this “nurslings of immortality” phrase and its directing to the key of D flat will be seen later in this work. For now, we hear the C and D flat struggle briefly in a bassoon trill, violently releasing twice into a sforzando b flat M7 chord. The first obligato instrument has made its appearance, and rejecting both C and D flat it propels the next movement into the key of B flat minor.
Move on to Part 3: Movement 2, “Below the Thunders of the Upper Deep.”
 See Footnote 17.
 By saying that the tonality is ambiguous, in this article we mean that it is difficult to place which recognizable triadic tonal structure it is creating. By saying a chord or phrase is chromatic, we mean that it includes semi-tone intervals that do not fit into the triadic harmony that the rest of the chord or line seems to indicate. Because of Britten’s frequent and purposeful use of triadic harmonies, it is justifiable to point out and find meaning in the places that he avoids them.
 “Adept,” Merriam-Webster’s Online Dictionary, (accessed Apr. 3, 2007), <http://www.m-w.com/dictionary/adept>.
 Cf. Wilfrid Mellers, “The Truth of the Dream,” The Britten Companion, 184-5.