Here it was less than night, and less than day,
  So that my sight could only move ahead
  slightly, but then I heard a bugle blast

so strong, it would have made a thunder clap
  seem faint; at this, my eyes--which doubled back
  upon their path--turned fully toward one place.

Not even Roland's horn, which followed on
  the sad defeat when Charlemagne had lost
  his holy army, was as dread as this.

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