In an article on secret hiding places in the Strand, December 1894, James Scott describes an ingenious refuge in the space between two matched flights of stairs. The functional set of risers on top can be raised to reveal a false set below, and the fugitive can take his place in the space between the two. When the door is closed again, searchers see only an ordinary staircase, and if they examine the empty cupboard beneath they’ll see only the apparent undersides of the risers above, which match them in number and size. There’s no perspective from which they can view the purported single stair from both above and below, and thus no reason to imagine that it might be double.

“Tapping upon what they believed to be the underside of the proper stairs would produce a hollow sound; but as a similar response must be expected when legitimate stairs are tapped, that point would not be considered a valuable clue,” Scott writes. “The quarters would be truly uncomfortable, as the necessities of the position would demand that the prisoner should lie at full length in the cavity. Perhaps, however, some provision was made whereby slight relief was afforded.”

David B. Lewis’ 1983 book Eureka!: Math Fun From Many Angles begins with this notice:

Errata

1. There are no mistakes in this book. The above should read ‘Erratum.’

Is the correction a mistake or not?

The Feuer Buech, a 1584 treatise on munitions by Franz Helm, contains a startling illustration: a cat and a bird approaching a town, each bearing a lighted explosive.

The image accompanies a section titled “To set fire to a castle or city which you can’t get at otherwise”; Penn curator Mitch Fraas translates the relevant section:

Create a small sack like a fire-arrow … if you would like to get at a town or castle, seek to obtain a cat from that place. And bind the sack to the back of the cat, ignite it, let it glow well and thereafter let the cat go, so it runs to the nearest castle or town, and out of fear it thinks to hide itself where it ends up in barn hay or straw it will be ignited.

Fortunately it appears this was never carried into practice … though possibly birds have been used for this purpose in Russia.

The concave side of a mask can produce the strong impression of a normal convex face. Our bias toward seeing faces as convex is so strong that we’ll favor this impression despite available cues that the object is hollow.

The same principle underlies this mistrustful dragon.

The cemetery at Aurora, Texas, bears a notable marker from the state’s historical commission: “This site is also well known because of the legend that a spaceship crashed nearby in 1897 and the pilot, killed in the crash, was buried here.”

An April 1897 article by S.E. Haydon in the Dallas Morning News explains that “the airship which has been sailing through the country” had had a fatal accident in Aurora:

It was traveling due north, and much nearer the earth than ever before. Evidently some of the machinery was out of order, for it was making a speed of only ten or twelve miles an hour and gradually settling toward the earth. It sailed directly over the public square, and when it reached the north part of town collided with the tower of Judge Proctor’s windmill and went to pieces with a terrific explosion, scattering debris over several acres of ground, wrecking the windmill and water tank and destroying the judge’s flower garden.

The pilot, purportedly a Martian, was carrying papers bearing indecipherable hieroglyphics. The ship, “built of an unknown metal,” was “too badly wrecked to form any conclusion as to its construction or motive power.”

The story has been inspiring investigations for more than a century, but one item stands out. In a 1980 interview in Time magazine, 86-year-old Aurora resident Etta Pegues said that Haydon had invented the story “as a joke and to bring interest to Aurora. The railroad bypassed us, and the town was dying.”

(Thanks, Meaghan.)