# Missing

The location of Alexander the Great’s tomb is a mystery. After Alexander’s death in Babylon in 323 B.C., his body was taken first to Memphis and then to Alexandria, where Pompey, Julius Caesar, Cleopatra, Augustus, and Caligula all visited his tomb. But by the 4th century A.D. the tomb’s location was no longer known. Egypt’s Supreme Council for Antiquities has now recognized more than 140 search attempts, but none has succeeded conclusively.

# The Empty Library

On May 10, 1933, in the Bebelplatz in central Berlin, members of the National Socialist Student Union burned 20,000 books, objecting to the “un-German spirit” of many Jewish, communist, and liberal authors. Joseph Goebbels declared that “the era of exaggerated Jewish intellectualism is now at an end … and the future German man will not just be a man of books … this late hour [I] entrust to the flames the intellectual garbage of the past.”

In 1995, Israeli sculptor Micha Ullman created a memorial room under the plaza, with empty shelves enough to accommodate 20,000 books. A plaque set into the cobblestones bears a quote by Heinrich Heine:

That was but a prelude;
where they burn books,
they will ultimately burn people as well.

# Enlightenment

You’re in a dark room. The only light comes from an old LED digital alarm clock with four seven-segment displays. The time is displayed in 24-hour format, HH:MM (no seconds), and the leading digit is blank if not used. How much time passes between the room’s darkest state and its lightest?

Friend John, whose (:) was removed,
When asked why he had lately proved
So free of caution and of fear,
Said, “I’ve no (*), my dear.”

— Willard R. Espy

# Mr. Lucky

In 1962, Croatian music teacher Frane Selak was riding from Sarajevo to Dubrovnik when his train jumped the rails and plunged into a river. Seventeen people died, but he escaped with hypothermia.

A year later a plane door malfunctioned and he was blown into midair. The plane crashed and he landed in a haystack.

Three years after that he was riding a bus that skidded into a river; he swam to safety. (“By this time my friends had stopped visiting me,” he said.)

In 1970 his car caught fire as he was driving it. He escaped before the fuel tank exploded.

Three years after that, another car caught fire; his hair was singed but he was otherwise unharmed.

In 1995 he was knocked down by a Zagreb bus but sustained only minor injuries.

The following year he nearly collided with a United Nations truck; he crashed through a mountain guardrail but managed to leap clear of the car.

In 2003, two days after his 73rd birthday, he won a lottery jackpot worth a million dollars. He married and bought two houses and a boat, and in 2010 gave away most of the rest to friends and family.

# Math Notes

$\displaystyle \sqrt{2\frac{2}{3}} = 2\sqrt{\frac{2}{3}}$

# “Dare to Be Yourself”

Quotations from André Gide:

Nothing prevents happiness like the memory of happiness.

Understanding is the beginning of approving.

The color of truth is gray.

At times it seems that I am living my life backward, and that at the approach of old age my real youth will begin.

Only fools don’t contradict themselves.

Do not do what someone else could do as well as you. Do not say, do not write what someone else could say, could write as well as you.

It is easier to lead men to combat, stirring up their passion, than to restrain them and direct them toward the patient labor of peace.

Believe those who are seeking the truth. Doubt those who find it.

To read a writer is for me not merely to get an idea of what he says, but to go off with him and travel in his company.

Most quarrels amplify a misunderstanding.

Fish die belly-upward and rise to the surface; it is their way of falling.

Our judgments about things vary according to the time left us to live — that we think is left us to live.

Art is a collaboration between God and the artist, and the less the artist does the better.

The most decisive actions of our life — I mean those that are most likely to decide the whole course of our future — are, more often than not, unconsidered.

# Brahmagupta’s Theorem

If a quadrilateral’s vertices lie on a common circle and if its diagonals are perpendicular, then a perpendicular to one side that passes through the intersection of the diagonals will bisect the opposite side.

# Podcast Episode 350: Symmes’ Hole

In 1818, Army veteran John Cleves Symmes Jr. declared that the earth was hollow and proposed to lead an expedition to its interior. He promoted the theory in lectures and even won support on Capitol Hill. In this week’s episode of the Futility Closet podcast we’ll describe Symmes’ strange project and its surprising consequences.

We’ll also revisit age fraud in sports and puzzle over a curious customer.

See full show notes …