in a railway train?  At that moment the man knocked down his own eye-glass with a gesture of annoyance; Turnbull remembered the gesture, and the truth sprang up solid in front of him.  The man with the moustaches was Cumberland Vane, the London police magistrate before whom he and MacIan had once stood on their trial.  The magistrate must have been transferred to some other official duties—­to something connected with the inspection of asylums.

Turnbull’s heart gave a leap of excitement which was half hope.  As a magistrate Mr. Cumberland Vane had been somewhat careless and shallow, but certainly kindly, and not inaccessible to common sense so long as it was put to him in strictly conventional language.  He was at least an authority of a more human and refreshing sort than the crank with the wagging beard or the fiend with the forked chin.

He went straight up to the magistrate, and said:  “Good evening, Mr. Vane; I doubt if you remember me.”

Cumberland Vane screwed the eye-glass into his scowling face for an instant, and then said curtly but not uncivilly:  “Yes, I remember you, sir; assault or battery, wasn’t it?—­a fellow broke your window.  A tall fellow—­McSomething—­case made rather a noise afterwards.”

“MacIan is the name, sir,” said Turnbull, respectfully; “I have him here with me.”

“Eh!” said Vane very sharply.  “Confound him!  Has he got anything to do with this game?”

“Mr. Vane,” said Turnbull, pacifically, “I will not pretend that either he or I acted quite decorously on that occasion.  You were very lenient with us, and did not treat us as criminals when you very well might.  So I am sure you will give us your testimony that, even if we were criminals, we are not lunatics in any legal or medical sense whatever.  I am sure you will use your influence for us.”

“My influence!” repeated the magistrate, with a slight start.  “I don’t quite understand you.”

“I don’t know in what capacity you are here,” continued Turnbull, gravely, “but a legal authority of your distinction must certainly be here in an important one.  Whether you are visiting and inspecting the place, or attached to it as some kind of permanent legal adviser, your opinion must still——­”

Cumberland Vane exploded with a detonation of oaths; his face was transfigured with fury and contempt, and yet in some odd way he did not seem specially angry with Turnbull.

“But Lord bless us and save us!” he gasped, at length; “I’m not here as an official at all.  I’m here as a patient.  The cursed pack of rat-catching chemists all say that I’ve lost my wits.”

“You!” cried Turnbull with terrible emphasis.  “You!  Lost your wits!”

In the rush of his real astonishment at this towering unreality Turnbull almost added:  “Why, you haven’t got any to lose.”  But he fortunately remembered the remains of his desperate diplomacy.

“This can’t go on,” he said, positively.  “Men like MacIan and I may suffer unjustly all our lives, but a man like you must have influence.”