The year of which I am now writing was the year of the famous Crystal Palace Exhibition in Hyde Park.  Foreigners in unusually large numbers had arrived already, and were still arriving in England.  Men were among us by hundreds whom the ceaseless distrustfulness of their governments had followed privately, by means of appointed agents, to our shores.  My surmises did not for a moment class a man of the Count’s abilities and social position with the ordinary rank and file of foreign spies.  I suspected him of holding a position of authority, of being entrusted by the government which he secretly served with the organisation and management of agents specially employed in this country, both men and women, and I believed Mrs. Rubelle, who had been so opportunely found to act as nurse at Blackwater Park, to be, in all probability, one of the number.

Assuming that this idea of mine had a foundation in truth, the position of the Count might prove to be more assailable than I had hitherto ventured to hope.  To whom could I apply to know something more of the man’s history and of the man himself than I knew now?

In this emergency it naturally occurred to my mind that a countryman of his own, on whom I could rely, might be the fittest person to help me.  The first man whom I thought of under these circumstances was also the only Italian with whom I was intimately acquainted—­my quaint little friend, Professor Pesca.

The professor has been so long absent from these pages that he has run some risk of being forgotten altogether.

It is the necessary law of such a story as mine that the persons concerned in it only appear when the course of events takes them up—­they come and go, not by favour of my personal partiality, but by right of their direct connection with the circumstances to be detailed.  For this reason, not Pesca alone, but my mother and sister as well, have been left far in the background of the narrative.  My visits to the Hampstead cottage, my mother’s belief in the denial of Laura’s identity which the conspiracy had accomplished, my vain efforts to overcome the prejudice on her part and on my sister’s to which, in their jealous affection for me, they both continued to adhere, the painful necessity which that prejudice imposed on me of concealing my marriage from them till they had learnt to do justice to my wife—­all these little domestic occurrences have been left unrecorded because they were not essential to the main interest of the story.  It is nothing that they added to my anxieties and embittered my disappointments—­ the steady march of events has inexorably passed them by.