She has hurried up behind Philander, and near-by can be seen the British soldier and Aunt Gwen, also pushing forward as rapidly as the assembling crowd will allow.

“Doctor Craig.”

Her presence recalls John to his senses.

“I am going to see my mother, Lady Ruth,” he says, as if apologizing for his rudeness.

“With whom?”

“This Sister.”

Lady Ruth surveys the other from her vail to the hem of her dress.

“I would advise you not to do so, doctor.”

“Why do you say that?” he asks, astonished.

“Because you will regret it, because you are being made the victim of another plot.”

“Lady Ruth, do I hear aright?  Do you fully realize what it is you say?”

“I am conscious of the gravity of the charge, but that does not prevent me from asserting it.  I repeat what I said before, that you are again the victim of a plot.  As to this Sister here, can it be possible you do not know her?”

He shakes his head.

“Have you seen her face?”

“It is old and shriveled—­that of a stranger.”

At this the Sister throws back her vail, and they see the features John describes.

“After all I am right,” says John, with the air of a man who attempts to justify himself.

At that the English girl laughs scornfully.

“Really, I did not think men could be so easily deceived, and one whom I considered as shrewd as you, Doctor Chicago.  See what a miserable deception, a fraud transferred from the boards of a New York theater to Algiers.  Behold! the magic wand touches age with a gentle touch, and what follows?”

Lady Ruth is standing between the two, and within arm’s length of either.

The Sister has not moved, but, as if confident of influencing John, holds her own.  She shoots daggers with her eyes at the English girl, but looks cannot hurt.

As Lady Ruth utters her last words, she makes a sudden move.

With a dexterous fling of an arm she succeeds in tearing from the Sister’s face the cleverly-made thin stage mask that was contrived to conceal the features of one who did a double act.

The professor laughs.

From the crowd that is still gathering various sounds arise, for no one can even give a guess as to the nature of the peculiar trick which is thus being enacted.

As for John Craig, he holds his breath at the stupendous nature of the disclosure, for little as he has dreamed of the fact, he sees before him the well-known features of Pauline Potter.

This queen of the stage has made even another attempt to get John, and might have succeeded only for the opportune coming of his friends.

He backs away from her.

“So, it is you again, wretched girl?” he exclaims, in something of righteous wrath.

She has lost once more, but this is frolic to one of her nature, and she laughs in his face.