This photo was taken at the reopening of the South Fork Bridge in Gold Bridge, British Columbia, in 1941. It’s sometimes claimed that the man at the center appears too modern to belong in such a crowd. It’s true that he’s dressed more casually than those around him, but the sunglasses he’s wearing first appeared in the 1920s, and his “T-shirt” appears to be a sweater with an emblem sewn on, possibly that of the Montreal Maroons, a contemporary hockey team. His camera is small for the time, but Kodak had begun offering portable cameras of that size three years earlier.

And no one around him seems to feel he’s out of place.

Each of these buses is proceeding smoothly along the striped street. Yet each seems to be varying its speed dramatically.

When the blue bus encounters a white stripe, it becomes easy to see due to the high contrast, so it appears to move faster. When it encounters a black stripe it becomes harder to see, so its movement seems slower. The reverse is true of the yellow bus. When the stripes are removed, the buses stop staggering.

UCSD psychologist Stuart Anstis first demonstrated the illusion in 2003.

What does this say? It’s an excerpt from a small bound volume given in 1841 by Harvard law professor Theophilus Parsons Jr. to John Davis of the Massachusetts Historical Society. Davis noted, “It was found in his father’s Library after his decease, its origin and contents unknown. I hoped to find some person of sufficient skill in stenography, to decipher the pages. But it is still, to me & those whom I have consulted, a Sealed Book.”

It seems to be a dated record of some kind. The anonymous writer used Arabic numerals, so we can see that the entries are organized by year, month, and day, with long entries on one side of each page and shorter ones on the other.

But no one has ever determined its meaning. It was conjectured that the volume might be the diary of a clergyman, perhaps Theophilus’ father, the Rev. Moses Parsons of Byfield, but the entries extend to 1799, 16 years after Moses’ death.

For now the diary (if that’s what it is) is kept at the Massachusetts Historical Society. MHS reference librarian Jeremy Dibbell writes about it here.

(Via Klaus Schmeh’s Encrypted Book List.)

Born with an orthopedic condition that caused her knees to bend backward, Ella Harper made a virtue of necessity and joined W.H. Harris’s Nickel Plate Circus, where she took up a starring role and earned $200 a week ($7,200 today). Her pitch card reads:

I am called the camel girl because my knees turn backward. I can walk best on my hands and feet as you see me in the picture. I have traveled considerably in the show business for the past four years and now, this is 1886 and I intend to quit the show business and go to school and fit myself for another occupation.

She married a schoolteacher in 1905 and died in 1921 at 51.

The peculiar architecture of Echo Bridge, in Newton, Massachusetts, will re-echo a human voice 18 times and a pistol shot (reportedly) 25 times.

In 1889 author Moses King wrote, “The favorite word to hurl at the arch is JULY, and the serious charge of lie — lie — lie is thrown back as vigorously and almost as frequently as if the bridge were a political newspaper in campaign time.”

In Riddles in Mathematics (1961), Eugene Northrop proposes that two men can simultaneously be each other’s uncle and nephew:

Mr. and Mrs. Allen … had a son Tom, and Mr. and Mrs. Black … had a son Dick. Mr. Allen and Mr. Black both died. And Tom and Dick, after they were grown men, each married the other’s mother. Dick and Mrs. Allen then had a son Harry, and Tom and Mrs. Black a son George. Now consider the relationship between Harry and George. Since Harry is the brother of Tom, George’s father, Harry must be George’s uncle. On the other hand George is the brother of Harry’s father, Dick, so Harry must be George’s nephew. In exactly the same way George is Harry’s uncle and nephew.

In Fun for the Family (1939), Jerome S. Meyer observes that if you father a son with the mother of your father’s second wife, and if your stepmother also has a son, then you can dine alone and still enjoy the company of your stepbrother’s nephew’s father, your father’s mother-in-law’s husband, and your stepmother’s father-in-law. Lewis Carroll considered a similar dinner.

Visiting a London bookshop in 1995 or 1996, British musician DJ Cylob noticed a pile of booklets near the entrance, with a note indicating that they were free. He asked an assistant about them, and she said that she knew nothing, only that a mysterious person was leaving them.

Each booklet consists of 20 pages of rectangular symbols. There are no letters or numbers, not even page numbers. Analysis shows that 24 different symbols make an appearance in the collection, which is consistent with encrypted English text, though some appear only at the beginning of the booklet and other very similar symbols only at the end.

The meaning of all this has never been discovered. One possibility is that the booklet is not a message at all but a game accessory. But then why does it contain no text? And why was someone silently offering it in a London bookshop?