lucas birdhouse

The birdhouse at George Lucas’ Skywalker Ranch is a replica of the 50,000-foot main house. Working from the original blueprints, architect Thomas Burke produced the structure in four months and installed it in April 2011. Roughly the size of a Volkswagen Beetle, it has four levels and 50 individual compartments, each with a separate entry made of PVC piping.

(Via Anne Schmauss, Birdhouses of the World, 2014.)

Tank Hunt

A puzzle from Daniel J. Velleman and Stan Wagon’s excellent 2020 problem collection Bicycle or Unicycle?:

Before you is a field of 225 squares arranged in a 15×15 grid. One of the squares contains a perfectly camouflaged tank that you’re trying to destroy. You have a weapon that will destroy one square of the grid with each shot, but it takes two shots to destroy the tank, and you know that when the tank has been hit the first time (and only then) it will flee invisibly to an adjacent square (horizontally or vertically). What’s the minimum number of shots you’ll need to be sure of destroying it?

Click for Answer

Simple Enough

These compounds are named housane, churchane, basketane, and penguinone.

Below: To celebrate the 2012 London Olympics, chemists Graham Richards and Antony Williams offered a molecule of five rings. They called it olympicene.


Hateful Spider, (You are quite right. It doesn’t matter a bit how one begins a letter, nor, for the matter of that, how one goes on with it, or even how one ends it — and it comes awfully easy, after a bit, to write coldly — easier, if possible, than to write warmly. For instance, I have been writing to the Dean, on College business, and began the letter ‘Obscure Animalcule,’ and he is foolish enough to pretend to be angry about it, and to say it wasn’t a proper style, and that he will propose to the Vice-Chancellor to expel me from the University: and it is all your fault!)

— Lewis Carroll, letter to Agnes Hull, April 30, 1881

Packing Numbers

Leonard Gordon noted this interesting pattern in the May 1995 issue of Word Ways. The English names of the first eight positive integers (ONE, TWO, THREE, FOUR, FIVE, SIX, SEVEN, EIGHT) contain altogether 32 letters. The smallest rectangular grid into which they can all be packed, word-search fashion, is 5×5. Because some of the cells serve double duty, the 32 letters “fit” into 25 cells; the ratio of these values is 1.28. This ratio remains remarkably consistent as the list of numbers is extended — here are grids for the first 8, 9, 10, 11, and 12 numbers:

E I G H T   O N E E R H T   E I G H T F   E L E V E N S   S E V E N O W T
F O U R W   S E V E N I N   F   X   W O   I   F S O I E   F I V E E R H T
X I S   O   E I G H T W O   N I N E O U   G   O I T N V   O G X N E N I N
S E V E N   F O U R X I S   S E V E N R   H W U X V E E   U H E V L E W T
T H R E E                   T H R E E     T H R E E E N   R T N E V E L E
 8 words     9 words        10 words      11 words        12 words
32 letters  36 letters      39 letters    45 letters      51 letters
25 cells    28 cells        30 cells      35 cells        40 cells
(1.28)      (1.29)          (1.30)        (1.29)          (1.28)

Alas, the last one isn’t optimal, Gordon notes. The names ONE through TWELVE will fit into a more compact grid:


… and that raises the ratio to 1.42 letters per cell.

(Leonard Gordon, “Packing the Cardinals,” Word Ways 28:2 [May 1995], 116.)

The Wine-Bin

A puzzle by Claude Gaspar Bachet de Méziriac, from 1612, via Henry Dudeney:

A gentleman had a wine-bin of eight compartments, as in the illustration, containing 60 bottles, arranged as shown. His dishonest servant stole 4 bottles and rearranged the remainder. The gentleman noticed that the bottles had been redistributed, but as there were still 21 bottles on every side he innocently concluded that all the 60 were there. The servant, emboldened by his success, again stole 4 bottles and rearranged the remainder without discovery. In fact, on two more occasions he repeated his theft of 4 bottles, always leaving the remainder so arranged symmetrically that there were 21 on every side. How did he arrange them on the four occasions so as to steal the 16 bottles?

Click for Answer

Travel Broadens the Mind

In 1971, physicist Joseph C. Hafele and astronomer Richard E. Keating bought airline tickets for a party of four to circle the world twice on commercial airliners. Each party consisted of Hafele, Keating, and two passengers named “Mr. Clock.”

The guests were cesium-beam atomic clocks. The researchers chaperoned the timepieces once eastward around the world and once westward. Then they compared the traveling clocks with one that had remained at the United States Naval Observatory.

The results were published in Science the following year. The clocks had been found to disagree, demonstrating the effects of kinematic and gravitational time dilation.

The total cost of the effort was $8,000. It’s been called one of the most inexpensive tests ever conducted of Einstein’s relativity.

“Fine Words Butter No Parsnips”

English proverbs:

Experience keeps a dear school. (1743)
Everybody stretches his legs according to the length of his coverlet. (1550)
He that would the daughter win, must with the mother first begin. (1578)
A still tongue makes a wise head. (1562)
Speak not of my debts unless you mean to pay them. (1640)
One of these days is none of these days. (1658)
One hand for yourself and one for the ship. (1799)
It’s never too late to mend. (1590)
The highest branch is not the safest roost. (1563)
He who is absent is always in the wrong. (1640)
The golden age was never the present age. (1732)
Example is better than precept. (1400)
Sweep your own doorstep clean. (1624)
Idle people have the least leisure. (1678)
He that would have eggs must endure the cackling of hens. (1659)

It Begins

Cockatoos in Sydney have mastered a five-step process for opening the lids of trash bins to reach the food inside.

“It was so exciting to observe such an ingenious and innovative way to access a food resource, we knew immediately that we had to systematically study this unique foraging behavior,” wrote behavioral ecologist Barbara Klump.

The birds learn the technique from one another, and cockatoos in different regions have worked out different techniques. Before 2018, the behavior had been reported in only three suburbs, but by the end of 2019 the number had reached 44.

“These results show the animals really learned the behavior from other cockatoos in their vicinity,” Klump wrote.

(Barbara C. Klump et al. “Innovation and Geographic Spread of a Complex Foraging Culture in an Urban Parrot,” Science 373:6553 [2021], 456-460.) (Thanks, Sharon.)