It had just struck ten next morning when Dr Mortimer and Sir Henry Baskerville knocked at the door of the house in Baker Street. The latter was a short dark-eyed man of about thirty with a sunburnt, energetic face. In his hand he was holding an envelope. \"This is Sir Henry Baskerville,\" said Dr Mortimer. \"Yes,\" he said, \"and the strange thing is, Mr Holmes, that if my friend had not suggested coming round to see you this morning I should have come anyhow. I know that you solve little puzzles, and I've had one this morning that I cannot solve. I have just received a strange letter and I want to show it to you.\" He laid the envelope on the table. The address \"Sir Henry Baskerville, Northumberland Hotel\" was written in capital letters. \"Who knew the address of your hotel?\" asked Holmes quickly. \"No one could have known it, because I decided to go there only after I had met Dr Mortimer.\" \"Really? Somebody is very much interested in you,\" said Holmes. He opened the envelope and took a large sheet of paper. There was only one sentence formed of printed words stuck upon the paper. \"If you value your life, keep away from the moor.\" Only the word \"moor\" was written in ink. \"Now,\" said Sir Henry Baskerville, \"perhaps you will tell me, Mr Holmes, what all this means?\" \"This interesting document was written and posted yesterday,\" said Holmes, looking at the stamp. \"Have you yesterday's copy of The Times, Watson?\" \"Here it is,\" said my friend, giving me the newspaper. Holmes glanced swiftly over the leading article and soon found where the words of the strange letter had been taken from. \"Someone has cut out these words and stuck them on the paper,\" said Holmes. \"The word 'moor' was written in ink, because it couldn't be found in the newspaper. It's less usual than the other words of this sentence. You can see that some words are stuck much higher than others. It shows that the writer of the letter was in a hurry, or perhaps he was afraid that somebody might see him. And now, Sir Henry, has anything else happened since your arrival in London?\" \"No, Mr Holmes, I think not.\" \"Are you sure that nobody follows you or watches you?\" \"Why do you ask me such strange questions, Mr Holmes? Do you know anything that I don't know?\" \"You will hear everything before you leave this room, Sir Henry. I promise you that,\" said Holmes. \"But first I want to know about the smallest incidents that have taken place since you came to London, anything unusual for everyday life.\" \"Well, I don't know much about British life yet. I have spent nearly all my time in America and Canada. But I hope that to lose one of your boots is not part of everyday life here in Britain,\" said Sir Henry with a smile. \"Have you lost one of your boots?\" \"Yes. I only bought this pair of boots last night and I haven't even worn them.\" \"And you think that one of them was stolen?\" \"Yes.\" \"This is very strange,\" said Sherlock Holmes, \"But I hope that this missing boot will soon be found. And now, Dr Mortimer, you must tell your story to Sir Henry as you told it to us.\"