Lee Sallows sent this clever puzzle, a followup to one we presented in 2010:
In the square shown above, any 3 counters in a straight line sum to 15.
Puzzle: Reposition the counters (again, one to each cell) to produce a new square again showing eight collinear triplets summing to 15, but with 1 now placed in a corner square.
We never did stop ad libbing. No two performances were ever quite the same. One matinee, during the second month in New York, I cooked up a little surprise for Groucho. During one of his quieter scenes, while I was offstage, I selected a blond cutie from the chorus, and asked her if she’d like a bigger part in the show. She was willing and eager. I told her all she had to do was run screaming across the stage. She did, and I tore after her in full pursuit, leaping and bounding and honking my horn. It broke up Groucho’s scene, but when the laughs subsided, Groucho was ready to top it. ‘First time I ever saw a taxi hail a passenger,’ he said.
— Harpo Marx, Harpo Speaks!, 1961
This is bewildering: This diamond isn’t moving, and its luminance and texture are unchanging. Yet when it’s surrounded with very thin edge strips whose luminance changes with respect to the background, the whole diamond seems to move. Using the controls at the bottom, you can even direct the illusion to send the diamond drifting “up,” “down,” “left,” or “right.” But it ain’t moving.
See the paper below for details.
(Oliver J. Flynn and Arthur G. Shapiro, “The Perpetual Diamond: Contrast Reversals Along Thin Edges Create the Appearance of Motion in Objects,” i-Perception 9:6 [2018], 2041669518815708.)
A densely imaginative little problem by Joseph C.J. Wainwright. White to mate in two moves.
Building Blocks, by Kumi Yamashita. “I sculpt using both light and shadow. I construct single or multiple objects and place them in relation to a single light source. The complete artwork is therefore comprised of both the material (the solid objects) and the immaterial (the light or shadow).”
Henry T. Brown’s 1868 mechanical encyclopedia Five Hundred and Seven Mechanical Movements is being animated on this fascinating site — see working demonstrations of hundreds of mechanical linkages from the age of steam.
Note that it’s a work in progress — the movements that have been animated are indicated with colored thumbnails. Owner Matt Keveney plans eventually to animate all 507 movements in Brown’s original text.
(Thanks, Sharon.)
“Consistency is the last refuge of the unimaginative.” — Oscar Wilde
“Consistency requires you to be as ignorant today as you were a year ago.” — Bernard Berenson
“Convictions are variable; to be always consistent is to be sometimes dishonest.” — Ambrose Bierce
In 1830 Joseph Palmer created an odd controversy in Fitchburg, Massachusetts: He wore a beard when beards were out of fashion. For this social sin he was shunned, attacked, and ultimately jailed. In this week’s episode of the Futility Closet podcast we’ll tell the story of a bizarre battle against irrational prejudice.
We’ll also see whether a computer can understand knitting and puzzle over an unrewarded long jump.
(Thanks, Sanford.)
Margaret Isabel Dicksee’s 1893 painting The Child Handel is based on a story about the composer’s childhood:
Handel’s father strongly opposed the child’s passionate love for music, and the more his great gifts developed the more severely was he forbidden to occupy himself with music. The little boy was obliged to have recourse to subterfuge, and when his elders believed him snug in bed he used to steal on tip-toe to the lumber-room, where he had discovered an old spinet, on which he played softly to his heart’s content, alone and fancy-free. In one of these moments of enjoyment, when the divine genius spoke to the child, he forgot himself and played louder and louder — all the sound of the old spinet streamed through the silent night, waking the sleepers in the house, who believed that the angels were keeping vigil over the old town of Halle. But little George’s father bethought himself of the musical propensities of the boy, and, as the latter was not to be found in his bed, the lantern was lit and a search-party followed where the music led them. Alas! Poor George was found, severely reprimanded, and dismissed to bed.
This telling is from the Strand, April 1904. The story is disputed, but Handel did display enough skill as a child to induce Duke Johann Adolf I to recommend him for musical instruction.
