They made no impression upon it at all.

Breathless and shaken, they looked at each other.

‘Suppose I fire into the lock?’ said Hugo.

‘We might try a key first,’ Albert answered.

He took the key from the door between the bedroom and the sitting-room, and applied it to the lock of the obstinate portal.  The obstinate portal opened at once.

‘Empty!’ ejaculated Albert, putting his nose into a small dressing-room.

With a gesture of disgust Hugo turned away.  In the same instant Simon withdrew his head into the sitting-room.

‘I’ve seen him,’ Simon whispered in hoarse excitement.  ’He just popped out of the kitchen and came half-way up the area steps.  Then he ran back.  He saw me looking at him.’

‘Ravengar?’

Simon nodded.  This was the hour of Simon’s triumph, the proof that he had not been mistaken in the theory which he had raised on the foundation of the photograph.

‘Come along,’ said Hugo grimly, preparing to rush downstairs.

But a singular thing had occurred.  While Simon had been staring out of the front window, and Hugo and Albert engaged in forcing a door which led to emptiness, the door of the sitting-room, the sole means of egress from the first-floor suite, had been shut and locked on the outside.

In vain Hugo assailed it with boot and shoulder; in vain Albert assisted him.

‘Keep your eye on the street, you fool!’ said Albert to Simon, when the latter offered to join the siege of the door.

Hugo and Albert multiplied their efforts.

‘There’s a cab driven up,’ Simon informed them from the window.  ’A man’s got out.  Now he’s gone down the area steps.  They’re carrying something up, something big.  Oh! look here, I must help you.’

And Simon ran to the door.  Before the triple assault it fell at last, and the three tumbled pell-mell downstairs into the hall.  The front-door was open.

A cab was just driving away.  It drove rapidly, very rapidly.

‘After it!’ Hugo commanded.

The hunt was up.

Two minutes afterwards another cab drove up to the door.

Ravengar and another man emerged from the area holding between them the form of a woman.  They got leisurely into the cab with the woman and departed.

CHAPTER XXVII

THE CEMETERY

Both Simon and Albert easily outran Hugo, and, fast as the first cab was travelling, they had gained on it by the time it turned into Victoria Street.  And at the turning an incident happened.  The driver, though hurried, was apparently to a certain extent careful and cautious, but he did not altogether avoid contact with a policeman at the corner.  The policeman was obliged to step sharply out of the way of the cab, and even then the sleeve of his immaculate tunic was soiled by contact with the hind-wheel of the vehicle.