midnight
Luckily , the old Frenchman was groping his way next the other wall . Pembroke slipped from behind the curtains and stole softly in pursuit . As he reached the south end of the corridor , he heard the latch of the Marquis 's door click softly . Alarmed by discovering that they were not in bed , thought Tom , he had abandoned whatever purpose he had in mind for his midnight prowl . After waiting a little and hearing no more , Tom went again to the window . The rain had begun now and the wind was blowing a gale . Suddenly Pembroke discerned a light shining from the window next the very one from which he was peering into the darkness , -- the steady glow of a deep red light .