'Over the stables.'
'We might possibly want him. Well, we can do no more until we see how things develop, Good-bye — but I expect that we shall see you before morning.'
It was nearly midnight before we took our station among some bushes immediately opposite the hall door of the professor. It was a fine night, but chilly, and we were glad of our warm overcoats. There was a breeze, and clouds were scudding across the sky, obscuring from time to time the half-moon. It would have been a dismal vigil were it not for the expectation and excitement which carried us along, and the assurance of my comrade that we had probably reached the end of the strange sequence of events which had engaged our attention.
'If the cycle of nine days holds good then we shall have the professor at his worst to-night,' said Holmes. 'The fact that these strange symptoms began after his visit to Prague, that he is in secret correspondence with a Bohemian dealer in London, who presumably represents someone in Prague, and that he received a packet from him this very day, all point in one direction. What he takes and why he takes it are still beyond our ken, but that it emanates in some way from Prague is clear enough. He takes it under definite directions which regulate this ninth- day system, which was the first point which attracted my attention. But his symptoms are most remarkable. Did you observe his knuckles?'
I had to confess that I did not.
'Thick and horny in a way which is quite new in my experience. Always look at the hands first, Watson. Then cuffs, trouserknees, and boots. Very curious knuckles which can only be explained by the mode of progression observed by—' Holmes paused and suddenly clapped his hand to his forehead. 'Oh, Watson, Watson, what a fool I have been! It seems incredible, and yet it must be true. All points in one direction. How could I miss seeing the connection of ideas? Those knuckles how could I have passed those knuckles? And the dog! And the ivy! It's surely time that I disappeared into that little farm of my dreams. Look out, Watson! Here he is! We shall have the chance of seeing for ourselves.'
The hall door had slowly opened, and against the lamplit background we saw the tall figure of Professor Presbury. He was clad in his dressing gown. As he stood outlined in the doorway he was erect but leaning forward with dangling arms, as when we saw him last.
Now he stepped forward into the drive, and an extraordinary change came over him. He sank down into a crouching position and moved along upon his hands and feet, skipping every now and then as if he were overflowing with energy and vitality. He moved along the face of the house and then round the corner. As he disappeared Bennett slipped through the hall door and softly followed him.
'Come, Watson, come!' cried Holmes, and we stole as softly as we could through the bushes until we had gained a spot whence we could see the other side of the house, which was bathed in the light of the half-moon. The professor was clearly visible crouching at the foot of the ivy-covered wall. As we watched him he suddenly began with incredible agility to ascend it. From branch to branch he sprang, sure of foot and firm of grasp, climbing apparently in mere joy at his own powers, with no definite object in view. With his dressing-gown flapping on each side of him, he looked like some huge bat glued against the side of his own house, a great square dark patch upon the moonlit wall. Presently he tired of this amusement, and, dropping from branch to branch, he squatted down into the old attitude and moved towards the stables, creeping along in the same strange way as before. The wolfhound was out now, barking furiously, and more excited than ever when it actually caught sight of its master. It was straining on its chain and quivering with eagerness and rage. The professor squatted down very deliberately just out of reach of the hound and began to provoke it in every possible way. He took handfuls of pebbles from the drive and threw them in the dog's face, prodded him with a stick which he had picked up, flicked his hands about only a few inches from the gaping mouth, and endeavoured in every way to increase the animal's fury, which was already beyond all control. In all our adventures I do not know that I have ever seen a more strange sight than this impassive and still dignified figure crouching frog-like upon the ground and goading to a wilder exhibition of passion the maddened hound, which ramped and raged in front of him, by all manner of ingenious and calculated cruelty.
And then in a moment it happened! It was not the chain that broke, but it was the collar that slipped, for it had been made for a thick-necked Newfoundland. We heard the rattle of falling metal, and the next instant dog and man were rolling on the ground together, the one roaring in rage, the other screaming in a strange shrill falsetto of terror. It was a very narrow thing for the professor's life. The savage creature had him fairly by the throat, its fangs had bitten deep, and he was senseless before we could reach them and drag the two apart. It might have been a dangerous task for us, but Bennett's voice and presence brought the great wolflhound instantly to reason. The uproar had brought the sleepy and astonished coachman from his room above the stables. 'I'm not surprised,' said he, shaking his head. 'I've seen him at it before. I knew the dog would get him sooner or later.'
The hound was secured, and together we carried the professor up to his room, where Bennett, who had a medical degree, helped me to dress his torn throat. The sharp teeth had passed dangerously near the carotid artery, and the haemorrhage was serious. In half an hour the danger was past, I had given the patient an injection of morphia, and he had sunk into deep sleep. Then, and only then, were we able to look at each other and to take stock of the situation.
'I think a first-class surgeon should see him,' said I.
'For God's sake, no!' cried Bennett. 'At present the scandal is confined to our own household. It is safe with us. If it gets beyond these walls it will never stop. Consider his position at the university, his European reputation, the feelings of his daughter.'
'Quite so,' said Holmes. 'I think it may be quite possible to keep the matter to ourselves, and also to prevent its recurrence now that we have a free hand. The key from the watch-chain, Mr. Bennett. Macphail will guard the patient and let us know if there is any change. Let us see what we can find in the professor's mysterious box.'
There was not much, but there was enough — an empty phial, another nearly full, a hypodermic syringe, several letters in a crabbed, foreign hand. The marks on the envelopes showed that they were those which had disturbed the routine of the secretary, and each was dated from the Commercial Road and signed 'A. Dorak.' They were mere invoices to say that a fresh bottle was being sent to Professor Presbury, or receipt to acknowledge money. There was one other envelope, however, in a more educated hand and bearing the Austrian stamp with the postmark of Prague. 'Here we have our material!' cried Holmes as he tore out the enclosure.
HONOURED COLLEAGUE [it ran]:
Since your esteemed visit I have thought much of your case, and though in your circumstances there are some special reasons for the treatment, I would none the less enjoin caution, as my results have shown that it is not without danger of a kind. It is possible that the serum of anthropoid would have been better. I have, as I explained to you, used black-faced langur because a specimen was accessible. Langur is, of course, a crawler and climber, while anthropoid walks erect and is in all ways nearer. I beg you to take every possible precaution that there be no premature revelation of the process. I have one other client in England, and Dorak is my agent for both. Weekly reports will oblige.
Yours with high esteem,
Lowenstein! The name brought back to me the memory of some snippet from a newspaper which spoke of an obscure scientist who was striving in some unknown way for the secret of rejuvenescence and the elixir of life. Lowenstein of Prague! Lowenstein with the wondrous strength-giving serum, tabooed by the profession because he refused to reveal its source. In a few words I said what I remembered. Bennett had taken a manual of zoology from the shelves. ''Langur,'' he read, ''the great black-faced monkey of the Himalayan slopes, biggest and most human of climbing monkeys.' Many details are added. Well, thanks to you, Mr. Holmes, it is very clear that we have traced the evil to its source.'
'The real source,' said Holmes, 'lies, of course, in that untimely love affair which gave our impetuous professor the idea that he could only gain his wish by turning himself into a younger man. When one tries to rise above Nature one is liable to fall below it. The highest type of man may revert to the animal if he leaves the straight road of destiny.' He sat musing for a little with the phial in his hand, looking at the clear liquid within. 'When I have written to this man and told him that I hold him criminally responsible for the poisons which he circulates, we will have no more trouble. But it may recur. Others may find a better way. There is danger there — a very real danger
