With a last howl of agony and a vicious snap in the air, it rolled upon its back, four feet pawing furiously, and then fell limp upon its side. I stooped, panting, and pressed my pistol to the dreadful, shimmering head, but it was useless to press the trigger. The giant hound was dead.

Sir Henry lay insensible where he had fallen. We tore away his collar, and Holmes breathed a prayer of gratitude when we saw that there was no sign of a wound and that the rescue had been in time.

Already our friend's eyelids shivered and he made a feeble effort to move. Lestrade thrust his brandy- flask between the baronet's teeth, and two frightened eyes were looking up at us.

`My God!' he whispered. `What was it? What, in heaven's name, was it?'

`It's dead, whatever it is,' said Holmes. `We've laid the family ghost once and forever.'

In mere size and strength it was a terrible creature which was lying stretched before us. It was not a pure bloodhound and it was not a pure mastiff; but it appeared to be a combination of the two - gaunt, savage, and as large as a small lioness. Even now in the stillness of death, the huge jaws seemed to be dripping with a bluish flame and the small, deep-set, cruel eyes were ringed with fire. I placed my hand upon the glowing muzzle, and as I held them up my own fingers smouldered and gleamed in the darkness.

`Phosphorus,' I said.

`A cunning preparation of it,' said Holmes, sniffing at the dead animal. `There is no smell which might have interfered with his power of scent. We owe you a deep apology, Sir Henry, for having exposed you to this fright. I was prepared for a hound, but not for such a creature as this. And the fog gave us little time to receive him.'

`You have saved my life.'

`Having first endangered it. Are you strong enough to stand?'

`Give me another mouthful of that brandy and I shall be ready for anything.

So! Now, if you will help me up. What do you propose to do?'

`To leave you here. You are not fit for further adventures to-night. If you will wait, one or other of us will go back with you to the Hall.'

He tried to stagger to his feet; but he was still ghastly pale and trembling in every limb. We helped him to a rock, where he sat shivering with his face buried in his hands.

`We must leave you now,' said Holmes. `The rest of our work must be done, and every moment is of importance. We have our case, and now we only want our man.

`It's a thousand to one against our finding him at the house,' he continued as we retraced our steps swiftly down the path. `Those shots must have told him that the game was up.'

`We were some distance off, and this fog may have deadened them.'

`He followed the hound to call him off - of that you may be certain. No, no, he's gone by this time! But we'll search the house and make sure.'

The front door was open, so we rushed in and hurried from room to room to the amazement of a doddering old manservant, who met us in the passage. There was no light save in the dining-room, but Holmes