was—­clad in some soft silvery stuff that gathered a thousand sparkles from the light of the moon,—­her fair hair caught up in a narrow circlet of diamonds, and her sweet face purely outlined against the dark worn stone of one of the great carved angel-wings.  But someone was with her,—­someone whom Fontenelle recognised at once by the classic shape of his head and bright curly hair,—­the man whom he had seen that very day on the Pincio,—­Aubrey Leigh.  With a jealous tightening at his heart, Fontenelle saw that Leigh held the soft plume of downy feathers which served Sylvie for a fan, and that he was lightly waving it to and fro as he talked to her in the musical, all-potent voice which had charmed thousands, and would surely not be without its fascination for the sensitive ears of a woman.  Moving a little closer he tried to hear what was being said,—­but Leigh spoke very softly, and Sylvie answered with equal softness, so that he could catch no distinct word.  Yet the mere tone of these two voices melted into a harmony more dulcet and perfect than could be endured by Fontenelle with composure, and uttering an impatient exclamation at his own folly he hastily left his retreat, and with one parting glance up at the picture of fair loveliness above him walked swiftly away.  Returning to his hotel he saw the letter that he had written to Sylvie lying on the table, and he at once posted it.  Then he began to prepare for his encounter with Miraudin.  He dressed quickly,—­wrote a few business letters,—­ and was about to lie down for a rest of an hour or so when the swift and furious galloping of a horse’s hoofs awoke the echoes of the quiet street, and almost before he had time to realise what had happened, his friend Ruspardi stood before him, breathless and wild with excitement.

“Marquis, you are tricked!” he cried, “Everything is prepared—­ seconds,—­pistols,—­all!  But your man—­your man has gone!”

“Gone!” exclaimed Fontenelle furiously, “Where?”

“Out of Rome!  In a common fiacre—­taking his latest mistress, one of the stage-women with him.  They were seen driving by the Porta Pia towards the Campagna half an hour ago!  He dare not face fire—­bully and coward that he is!”

“I will go after him!” said Fontenelle promptly, “Half an hour ahead, you say!  Good!—­I will catch him up.  Can I get a horse anywhere?”

“Take mine,” said Ruspardi eagerly, “he is perfectly fresh—­just out of the stable.  Have you weapons?”

“Yes,” and the Marquis unlocked a case, and loading two, placed them in a travelling holder.  Then, turning to Ruspardi he shook hands.

“Thanks, a thousand times!  There are a few letters here—­see to them if I should not come back.”

“What are you going to do?” asked Ruspardi, his excitement beginning to cool a little, now that he saw the possible danger into which Fontenelle was voluntarily rushing.

“Persuade the worthy mountebank either to come back or fight at once on whatever ground I find him, and assume to be a gentleman—­for once!” said Fontenelle, carelessly.  “Addio!”