The poet, masked and unattended, rejoined his friend without a word; and Odo guessed in him an eye and ear alert for pursuit.  Guided by the pressure of his arm, Odo was hurried round the bend of the lane, up a transverse alley and across a little square lost between high shuttered buildings.  Alfieri, at his first word, gripped his arm with a backward glance; then urged him on under the denser blackness of an arched passage-way, at the end of which an oil-light glimmered.  Here a gate in a wall confronted them.  It opened at Alfieri’s tap and Odo scented wet box-borders and felt the gravel of a path under foot.  The gate was at once locked behind them and they entered the ground-floor of a house as dark as the garden.  Here a maid-servant of close aspect met them with a lamp and preceded them upstairs to a bare landing hung with charts and portulani.  On Odo’s flushed anticipations this antechamber, which seemed the approach to some pedant’s cabinet, had an effect undeniably chilling; but Alfieri, heedless of his surprise, had cast off cloak and mask, and now led the way into a long conventual-looking room lined with book-shelves.  A knot of middle-aged gentlemen of sober dress and manner, gathered about a cabinet of fossils in the centre of this apartment, looked up at the entrance of the two friends; then the group divided, and Odo with a start recognised the girl he had seen on the road to the Superga.

She bowed gravely to the young men.  “My father,” said she, in a clear voice without trace of diffidence, “has gone to his study for a book, but will be with you in a moment.”

She wore a dress in keeping with her manner, its black stuff folds and the lawn kerchief crossed on her bosom giving height and authority to her slight figure.  The dark unpowdered hair drawn back over a cushion made a severer setting for her face than the fluctuating brim of her shade-hat; and this perhaps added to the sense of estrangement with which Odo gazed at her; but she met his look with a smile, and instantly the rosy girl flashed through her grave exterior.

“Here is my father,” said she; and her companion of the previous day stepped into the room with several folios under his arm.

Alfieri turned to Odo.  “This, my dear Odo,” said he, “is my distinguished friend, Professor Vivaldi, who has done us the honour of inviting us to his house.”  He took the Professor’s hand.  “I have brought you,” he continued, “the friend you were kind enough to include in your invitation—­the Cavaliere Odo Valsecca.”

Vivaldi bowed.  “Count Alfieri’s friends,” said he, “are always welcome to my house; though I fear there is here little to interest a young gentleman of the Cavaliere Valsecca’s years.”  And Odo detected a shade of doubt in his glance.

“The Cavaliere Valsecca,” Alfieri smilingly rejoined, “is above his years in wit and learning, and I answer for his interest as I do for his discretion.”

The Professor bowed again.  “Count Alfieri, sir,” he said, “has doubtless explained to you the necessity that obliges me to be so private in receiving my friends; and now perhaps you will join these gentlemen in examining some rare fossil fish newly sent me from the Monte Bolca.”