"May I ask if he is going to honour us with a visit himself?"
"He cannot leave town at present. He has other cases which engage his attention."
"What a pity! He might throw some light on that which is so dark to us. But as to your own researches, if there is any possible way in which I can be of service to you I trust that you will command me. If I had any indication of the nature of your suspicions or how you propose to investigate the case, I might perhaps even now give you some aid or advice."
"I assure you that I am simply here upon a visit to my friend, Sir Henry, and that I need no help of any kind."
"Excellent!" said Stapleton. "You are perfectly right to be wary and discreet. I am justly reproved for what I feel was an unjustifiable intrusion, and I promise you that I will not mention the matter again."
We had come to a point where a narrow grassy path struck off from the road and wound away across the moor. A steep, boulder-sprinkled hill lay upon the right which had in bygone days been cut into a granite quarry. The face which was turned towards us formed a dark cliff, with ferns and brambles growing in its niches. From over a distant rise there floated a grey plume of smoke.
"A moderate walk along this moor-path brings us to Merripit House," said he. "Perhaps you will spare an hour that I may have the pleasure of introducing you to my sister."
My first thought was that I should be by Sir Henry's side. But then I remembered the pile of papers and bills with which his study table was littered. It was certain that I could not help with those. And Holmes had expressly said that I should study the neighbours upon the moor. I accepted Stapleton's invitation, and we turned together down the path.
"It is a wonderful place, the moor," said he, looking round over the undulating downs, long green rollers, with crests of jagged granite foaming up into fantastic surges. "You never tire of the moor. You cannot think the wonderful secrets which it contains. It is so vast, and so barren, and so mysterious."
"You know it well, then?"
"I have only been here two years. The residents would call me a new comer. We came shortly after Sir Charles settled. But my tastes led me to explore every part of the country round, and I should think that there are few men who know it better than I do."
"Is it hard to know?"
"Very hard. You see, for example, this great plain to the north here with the queer hills breaking out of it. Do you observe anything remarkable about that?"
"It would be a rare place for a gallop."
"You would naturally think so and the thought has cost several their lives before now. You notice those bright green spots scattered thickly over it?"
"Yes, they seem more fertile than the rest."
Stapleton laughed.
"That is the great Grimpen Mire," said he. "A false step yonder means death to man or beast. Only yesterday I saw one of the moor ponies wander into it. He never came out. I saw his head for quite a long time craning out of the bog-hole, but it sucked him down at last. Even in dry seasons it is a danger to cross it, but after these autumn rains it is an awful place. And yet I can find my way to the very heart of it and return alive. By George, there is another of those miserable ponies!"
Something brown was rolling and tossing among the green sedges. Then a long, agonised, writhing neck shot upward and a dreadful cry echoed over the moor. It turned me cold with horror, but my companion's nerves seemed to be stronger than mine.
"It's gone!" said he. "The mire has him. Two in two days, and many more, perhaps, for they get in the way of going there in the dry weather, and never know the difference until the mire has them in its clutches. It's a bad place, the great Grimpen Mire."
"And you say you can penetrate it?"
"Yes, there are one or two paths which a very active man can take. I have found them out."
"But why should you wish to go into so horrible a place?"
"Well, you see the hills beyond? They are really islands cut off on all sides by the impassable mire, which has crawled round them in the course of years. That is where the rare plants and the butterflies are, if you have the wit to reach them."
"I shall try my luck some day."
He looked at me with a surprised face.
"For God's sake put such an idea out of your mind," said he.
"Your blood would be upon my head. I assure you that there would not be the least chance of your coming back alive. It is only by remembering certain complex landmarks that I am able to do it."
"Halloa!" I cried. "What is that?"
A long, low moan, indescribably sad, swept over the moor. It filled the whole air, and yet it was impossible to say whence it came. From a dull murmur it swelled into a deep roar, and then sank back into a melancholy, throbbing murmur once again. Stapleton looked at me with a curious expression in his face.
"Queer place, the moor!" said he.
"But what is it?"
"The peasants say it is the Hound of the Baskervilles calling for its prey. I've heard it once or twice before, but never quite so loud."
I looked round, with a chill of fear in my heart, at the huge swelling plain, mottled with the green patches of rushes. Nothing stirred over the vast expanse save a pair of ravens, which croaked loudly from a tor behind us.
"You are an educated man. You don't believe such nonsense as that?" said I. "What do you think is the cause of so strange a sound?"
"Bogs make queer noises sometimes. It's the mud settling, or the water rising, or something."
"No, no, that was a living voice."
"Well, perhaps it was. Did you ever hear a bittern booming?"
"No, I never did."
"It's a very rare bird—practically extinct—in England now, but all things are possible upon the moor. Yes, I should not be surprised to learn that what we have heard is the cry of the last of the bitterns."
"It's the weirdest, strangest thing that ever I heard in my life."
"Yes, it's rather an uncanny place altogether. Look at the hillside yonder. What do you make of those?"
The whole steep slope was covered with grey circular rings of stone, a score of them at least.
"What are they? Sheep-pens?"
"No, they are the homes of our worthy ancestors. Prehistoric man lived thickly on the moor, and as no one in particular has lived there since, we find all his little arrangements exactly as he left them. These are his wigwams with the roofs off. You can even see his hearth and his couch if you have the curiosity to go inside.
"But it is quite a town. When was it inhabited?"
"Neolithic man—no date."
"What did he do?"
"He grazed his cattle on these slopes, and he learned to dig for tin when the bronze sword began to supersede the stone axe. Look at the great trench in the opposite hill. That is his mark. Yes, you will find some very singular points about the moor, Dr. Watson. Oh, excuse me an instant! It is surely Cyclopides."
A small fly or moth had fluttered across our path, and in an instant Stapleton was rushing with extraordinary energy and speed in pursuit of it. To my dismay the creature flew straight for the great mire, and my acquaintance never paused for an instant, bounding from tuft to tuft behind it, his green net waving in the air. His grey clothes and jerky, zigzag, irregular progress made him not unlike some huge moth himself. I was standing watching his pursuit with a mixture of admiration for his extraordinary activity and fear lest he should lose his footing in the treacherous