A passion of which the outlets are sealed, begets a tension of nerve,
in which the sensible world comes to one with a reinforced brilliancy
and relief--all redness is turned into blood, all water into tears.
Hence a wild, convulsed sensuousness in the poetry of the Middle Age,
in which the things of nature begin to play a strange delirious part.
Of the things of nature the medieval mind had a deep sense; but its
sense of them was not objective, no real escape [219] to the world
without us. The aspects and motions of nature only reinforced its
prevailing mood, and were in conspiracy with one's own brain against
one. A single sentiment invaded the world: everything was infused
with a motive drawn from the soul. The amorous poetry of Provence,
making the starling and the swallow its messengers, illustrates the
whole attitude of nature in this electric atmosphere, bent as by
miracle or magic to the service of human passion.

The most popular and gracious form of Provencal poetry was the
nocturn, sung by the lover at night at the door or under the window
of his mistress. These songs were of different kinds, according to
the hour at which they were intended to be sung. Some were to be
sung at midnight--songs inviting to sleep, the serena, or serenade;
others at break of day--waking songs, the aube or aubade.* This
waking-song is put sometimes into the mouth of a comrade of the
lover, who plays sentinel during the night, to watch for and announce
the dawn: sometimes into the mouth of one of the lovers, who are
about to separate. A modification of it is familiar to us all in
Romeo and Juliet, where the lovers debate whether the song they hear
is of the nightingale or the lark; the aubade, with the two other
great forms of love-poetry then floating in the world, the sonnet and
the [220] epithalamium, being here refined, heightened, and inwoven