Tempting

The Earl of Yarborough offers you a wager. He’ll shuffle an ordinary deck and deal you 13 cards. If none of your cards ranks above 9, he’ll give you a thousand pounds. Otherwise you must give him one pound.

Should you accept?

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Hey Presto!

A bit of conjuring adapted from Augustus de Morgan:

1. Think of a one-digit number and remember it. (Example: 4.)

2. Write down a number of any length. Jumble the figures into another number, and subtract one from the other:

de morgan

3. Count the letters in your father’s first name, your state capital, and the name of your favorite Beatle, and add them together.

4. Multiply this number by 4 and its reverse by 5. Add these together, plus the number from step 1.

For example, suppose your father’s name is William, your state capital is Oklahoma City, and you choose Paul. That’s 23 letters in all, and 23 reversed is 32. (4 × 23) + (5 × 32) + 4 = 256.

5. Mix these figures (256) into the result from step 2 (4600708659), in any order, say 4560207086569.

Seeing nothing but this final list of figures, the conjurer names the one-digit number from step 1.

How does he do it?

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The Rejected Gun

From Henry Dudeney:

Here is a little military puzzle that may not give you a moment’s difficulty. It is such a simple question that a child can understand it and no knowledge of artillery is required. Yet some of my readers may find themselves perplexed for quite five minutes.

An inventor offered a new large gun to the committee appointed by our government for the consideration of such things. He declared that when once loaded it would fire 60 shots at the rate of a shot a minute. The War Office put it to the test and found that it fired 60 shots an hour, but declined it “as it did not fulfill the promised condition.”

“Absurd,” said the inventor, “for you have shown that it clearly does all that we undertook it should do.”

“Nothing of the sort,” said the experts. “It has failed.”

Can you explain this extraordinary mystery? Was the inventor, or were the experts, right?

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What Is It?

Here’s one of the most beautiful riddles in the English language. It’s commonly attributed to Byron, but it was composed in 1814 by Catherine Maria Fanshawe, the daughter of a Surrey squire:

‘Twas whispered in heaven, ’twas muttered in hell,
And echo caught faintly the sound as it fell;
On the confines of earth ’twas permitted to rest,
And the depths of the ocean its presence confessed.
‘Twill be found in the sphere when ’tis riven asunder;
‘Tis seen in the lightning, and heard in the thunder.
‘Twas allotted to man from his earliest breath;
It assists at his birth, and attends him in death;
It presides o’er his happiness, honour, and health;
Is the prop of his house, and the end of his wealth.
In the heap of the miser ’tis hoarded with care,
But is sure to be lost in his prodigal heir.
It begins every hope, every wish it must bound,
It prays with the hermit, with monarchs is crowned.
Without it the soldier and seaman may roam,
But woe to the wretch who expels it from home.
In the whispers of conscience ’tis sure to be found;
Nor e’en in the whirlwind of passion is drowned.
‘Twill soften the heart, and though deaf to the ear,
‘Twill make it acutely and constantly hear.
But, in short, let it rest like a beautiful flower;
Oh, breathe on it softly, it dies in an hour.

What is it?

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Thrilling Peril!

http://commons.wikimedia.org/wiki/File:Mars_Twin_Peaks_(1024px).jpg

Amy, Bob, Cindy, and Dave are the last four colonists on Mars, which is being overrun by Hideous Sand Beetles. The last evacuation ship leaves in 16 minutes. To reach it, they must pass through the Soul-Freezing Tunnel of Yx, which can accommodate only two people at a time. And anyone passing through the tunnel must light his way with the Fabulous Oracle of Zeb. (Mars is very dramatic.)

  • Amy can travel the tunnel in 1 minute.
  • Bob can travel the tunnel in 2 minutes.
  • Cindy can travel the tunnel in 5 minutes.
  • Dave can travel the tunnel in 8 minutes.

This is a problem. If Amy and Dave go first, they’ll reach the other side in 8 minutes (Dave’s top speed). If Amy then runs back and escorts Cindy, and then Bob, she and Bob will be only halfway through the tunnel when the ship departs. Are they doomed?

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Cast Away

Here’s a paragraph from Robinson Crusoe. It contains a remarkable error — can you spot it?

A little after noon, I found the sea very calm, and the tide ebbed so far out, that I could come within a quarter of a mile of the ship; and here I found a fresh renewing of my grief: for I saw evidently, that if we had kept on board, we had been all safe–that is to say, we had all got safe on shore, and I had not been so miserable as to be left entirely destitute of all comfort and company, as I now was. This forced tears from my eyes again; but as there was little relief in that, I resolved, if possible, to get to the ship–so I pulled off my clothes, for the weather was hot to extremity, and took the water. But when I came to the ship, my difficulty was still greater to know how to get on board; for, as she lay aground and high out of the water, there was nothing within my reach to lay hold of. I swam round her twice, and the second time I spied a small piece of rope, which I wondered I did not see at first, hang down by the fore-chains, so low as that with great difficulty I got hold of it, and, by the help of that rope, got up into the forecastle of the ship. Here I found that the ship was bulged, and had a great deal of water in her hold, but that she lay so on the side of a bank of hard sand, or rather earth, and her stern lay lifted up upon the bank, and her head low almost to the water: by this means all her quarter was free, and all that was in that part was dry; for you may be sure my first work was to search and to see what was spoiled, and what was free, and first I found that all the ship’s provisions were dry and untouched by the water: and being very well disposed to eat, I went to the bread-room and filled my pockets with biscuit, and ate it as I went about other things, for I had no time to lose. I also found some rum in the great cabin, of which I took a large dram, and which I had indeed need enough of to spirit me for what was before me. Now I wanted nothing but a boat, to furnish myself with many things which I foresaw would be very necessary to me.

(He does explain later that “I found the tide begin to flow, though very calm; and I had the mortification to see my coat, shirt, and waistcoat, which I had left on the shore, upon the sand, swim away. As for my breeches, which were only linen, and open-kneed, I swam on board in them and my stockings.”)

A Question Without an Answer

http://books.google.com/books?id=ysACAAAAMAAJ&pg=PT2&dq=%22sam+loyd%22&as_brr=1&ei=hyxhSYhfpMYyhryR0QE#PPT2,M1

In 1905, the Ingersoll company engaged Sam Loyd to invent a puzzle to promote its new dollar watch. Loyd sent the illustration above and asked:

How soon will the hour, minute and second hands again appear equal distances apart?

The company advertised the puzzle in Scribner’s in June, promising a free watch to the first 10,000 correct respondents. “The full problem is stated above,” the ad ran, “and no further information can be given in fairness to all contestants.” Further, it said, Loyd’s solution “is locked in our safe, inaccessible to any one.”

Perhaps it still is — I can’t find any record of a solution to the puzzle. I offer it here for what it’s worth.