“Our tawny friend?”

“Possibly.  Only he was not really tawny.”  Mr. Carlyle’s easy attitude suddenly stiffened into rigid attention.  “He wore a false moustache.”

“He wore a false moustache!” repeated the amazed gentleman.  “And you cannot see!  No, really, Max, this is beyond the limit!”

“If only you would not trust your dear, blundering old eyes so implicitly you would get nearer that limit yourself,” retorted Carrados.  “The man carried a five-yard aura of spirit gum, emphasized by a warm, perspiring skin.  That inevitably suggested one thing.  I looked for further evidence of making-up and found it—­these preparations all smell.  The hair you described was characteristically that of a wig—­worn long to hide the joining and made wavy to minimize the length.  All these things are trifles.  As yet we have not gone beyond the initial stage of suspicion.  I will tell you another trifle.  When this man retired to a compartment with his deed-box, he never even opened it.  Possibly it contains a brick and a newspaper.  He is only watching.”

“Watching the bookmaker.”

“True, but it may go far wider than that.  Everything points to a plot of careful elaboration.  Still, if you are satisfied—­”

“I am quite satisfied,” replied Mr. Carlyle gallantly.  “I regard ’The Safe’ almost as a national institution, and as such I have an implicit faith in its precautions against every kind of force or fraud.”  So far Mr. Carlyle’s attitude had been suggestive of a rock, but at this point he took out his watch, hummed a little to pass the time, consulted his watch again, and continued:  “I am afraid that there were one or two papers which I overlooked.  It would perhaps save me coming again to-morrow if I went back now—­”

“Quite so,” acquiesced Carrados, with perfect gravity.  “I will wait for you.”

For twenty minutes he sat there, drinking an occasional tiny cup of boiled coffee and to all appearance placidly enjoying the quaint atmosphere which Mr. Mehmed had contrived to transplant from the shores of the Persian Gulf.

At the end of that period Carlyle returned, politely effusive about the time he had kept his friend waiting but otherwise bland and unassailable.  Anyone with eyes might have noticed that he carried a parcel of about the same size and dimensions as the deed-box that fitted his safe.

The next day Carrados presented himself at the safe-deposit as an intending renter.  The manager showed him over the vaults and strong-rooms, explaining the various precautions taken to render the guile or force of man impotent:  the strength of the chilled-steel walls, the casing of electricity-resisting concrete, the stupendous isolation of the whole inner fabric on metal pillars so that the watchman, while inside the building, could walk above, below, and all round the outer walls of what was really—­although it bore no actual relationship to the advertising device of the front—­a monstrous safe; and, finally, the arrangement which would enable the basement to be flooded with steam within three minutes of an alarm.  These details were public property.  “The Safe” was a showplace and its directors held that no harm could come of displaying a strong hand.