he tried to rouse him, but could not.  A doctor who was called pronounced that he was suffering from some sort of poisoning.  He was taken to St. George’s Hospital in an ambulance, but he never recovered.  The post-mortem investigation showed a small scratch on the palm of the hand.  That scratch had been produced by a pin or a needle which had been infected by one of the newly discovered poisons which, administered secretly, give a post-mortem appearance of death from heart disease.”

“Then your father was murdered—­eh?” exclaimed the elder man.

“Most certainly he was.  And that woman is aware of the whole circumstances and of the identity of the assassin.”

“How do you know that?”

“By a letter I afterwards opened—­one that had been addressed to him at Woodthorpe in his absence.  It was anonymous, written in bad English, in an illiterate hand, warning him to ’beware of that woman you know—­Mademoiselle of Monte Carlo.’  It bore the French stamp and the postmark of Tours.”

“I never knew all this,” Brock said.  “You are quite right, Hugh!  The whole affair is a tangled mystery.  But the first point we must establish before we commence to investigate is—­who is Mademoiselle of Monte Carlo?”

SECOND CHAPTER

CONCERNS A GUILTY SECRET

Just after seven o’clock that same evening young Henfrey and his friend Brock met in the small lounge of the Hotel des Palmiers, a rather obscure little establishment in the Avenue de la Costa, behind the Gardens, much frequented by the habitues of the Rooms who know Monte Carlo and prefer the little place to life at the Paris, the Hermitage, and the Riviera Palace, or the Gallia, up at Beausoleil.

The Palmiers was a place where one met a merry cosmopolitan crowd, but where the cocotte in her bright plumage was absent—­an advantage which only the male habitue of Monte Carlo can fully realize.  The eternal feminine is always so very much in evidence around the Casino, and the most smartly dressed woman whom one might easily take for the wife of an eminent politician or financier will deplore her bad luck and beg for “a little loan.”

“Well,” said Hugh as his friend came down from his room to the lounge, “I suppose we ought to be going—­eh?  Dorise said half-past seven, and we’ll just get across to the Metropole in time.  Lady Ranscomb is always awfully punctual at home, and I expect she carries out her time-table here.”

The two men put on light overcoats over their dinner-jackets and strolled in the warm dusk across the Gardens and up the Galerie, with its expensive little shops, past the original Ciro’s to the Metropole.