Leap Day

Alice gets a rocket-powered pogo stick for her birthday. She jumps 1 foot on the first hop, 2 feet on the second, then 4, 8, and so on. This gets alarming. By judicious hopping, can she arrange to return to her starting point?

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Hello Goodbye

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In 1902, disgusted with the “characteristic American custom of promiscuous, unsought and unauthorized introductions,” Ambrose Bierce proposed a new social convention — disintroductions:

Mr. White–Mr. Black, knowing the low esteem in which you hold each other, I have the honor to disintroduce you from Mr. Green.

Mr. Black (bowing)–Sir, I have long desired the advantage of your unacquaintance.

Mr. Green (bowing)–Charmed to unmeet you, sir. Our acquaintance (the work of a most inconsiderate and unworthy person) has distressed me beyond expression. We are greatly indebted to our good friend here for his tact in repairing the mischance.

Mr. White–Thank you. I’m sure you will become very good strangers.

“This is only the ghost of a suggestion,” Bierce wrote. “Of course the plan is capable of an infinite elaboration. Its capital defect is that the persons who are now so liberal with their unwelcome introductions, will be equally lavish with their disintroductions, and will estrange the best of friends with as little ceremony as they now observe in their more fiendish work.”

Desperate Measuring

desperate measuring

You’re alone on a desert island and want to lay out a course for some snail races. Unfortunately, you have only an 8.5 x 11 inch sheet of paper. How can you use it to measure exactly 3 inches?

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King of the Hill

On Tuesday week, as the coal train on the Swannington line was proceeding to Leicester, and when near Glenfield, the engine-driver suddenly perceived a fine bullock appear on the line, and turn to meet the train, head to head with the engine. The animal ran directly up to its fiery antagonist, and by the contact was killed on the spot. There was no time to stop the train before the infuriated beast came up. It was afterwards discovered that the animal belonged to Mr. Hassell, of Glenfield, and made its way on to the line from the field adjoining.

Leicester Journal, reprinted in the Times, Aug. 10, 1849

The Last Cent

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You and a friend are playing a game. Between you is a pile of 15 pennies. You’ll take turns removing pennies from the pile — each of you, on his turn, can choose to remove 1, 2, or 3 pennies. The loser is the one who removes the last penny.

You go first. How should you play?

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After Hours

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When the Cavendish Laboratory at Cambridge University instituted an annual dinner in 1897, it began a tradition of “postprandial proceedings” — typically songs sung around a piano. This air, “Ions Mine,” was sung to the tune of “Clementine”:

In the dusty lab’ratory,
‘Mid the coils and wax and twine,
There the atoms in their glory
Ionize and recombine.

(chorus) Oh my darlings! Oh my darlings!
Oh my darling ions mine!
You are lost and gone forever
When just once you recombine!

In a tube quite electrodeless,
They discharge around a line,
And the glow they leave behind them
Is quite corking for a time.

(repeat chorus)

And with quite a small expansion,
1.8 or 1.9,
You can get a cloud delightful,
Which explains both snow and rain.

(repeat chorus)

In the weird magnetic circuit
See how lovingly they twine,
As each ion describes a spiral
Round its own magnetic line.

(repeat chorus)

Ultra-violet radiation
From the arc of glowing lime,
Soon discharges a conductor
If it’s charged with minus sign.

(repeat chorus)

Alpha rays from radium bromide
Cause a zinc-blende screen to shine,
Set it glowing, clearly showing
Scintillations all the time.

(repeat chorus)

Radium bromide emanation,
Rutherford did first divine,
Turns to helium, then Sir William
Got the spectrum, every line.

(repeat chorus)

The fourth verse was contributed by J.J. Thomson himself.

Fish Story

I release a fish at the edge of a circular pool. It swims 80 feet in a straight line and bumps into the wall. It turns 90 degrees, swims another 60 feet, and hits the wall again. How wide is the pool?

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Man and Machine

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William Dean Howells to Mark Twain, Nov. 5, 1875:

The type-writer came Wednesday night, and is already beginning to have its effect on me. Of course it doesn’t work: if I can persuade some of the letters to get up against the ribbon they won’t get down again without digital assistance. The treadle refuses to have any part or parcel in the performance; and I don’t know how to get the roller to turn with the paper. Nevertheless I have begun several letters to My d ar lemans, as it prefers to spell your respected name, and I don’t despair yet of sending you something in its beautiful handwriting–after I’ve had a man out from the agent’s to put it in order. It’s fascinating in the meantime, and it wastes my time like an old friend.

E.B. White on the Model T, 1936:

During my association with Model Ts, self-starters were not a prevalent accessory. They were expensive and under suspicion. Your car came equipped with a serviceable crank, and the first thing you learned was how to Get Results. It was a special trick, and until you learned it (usually from another Ford owner, but sometimes by a period of appalling experimentation) you might as well have been winding up an awning. The trick was to leave the ignition switch off, proceed to the animal’s head, pull the choke (which was a little wire protruding through the radiator) and give the crank two or three nonchalant upward lifts. Then, whistling as though thinking about something else, you would saunter back to the driver’s cabin, turn the ignition on, return to the crank, and this time, catching it on the down stroke, give it a quick spin with plenty of that. If this procedure was followed, the engine almost always responded — first with a few scattered explosions, then with a tumultuous gunfire, which you checked by racing around to the driver’s seat and retarding the throttle. Often, if the emergency brake hadn’t been pulled all the way back, the car advanced on you the instant the first explosion occurred and you would hold it back by leaning your weight against it. I can still feel my old Ford nuzzling me at the curb, as though looking for an apple in my pocket.

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