Dye reveals presence of a rip current

Beach umbrella and people (dots) for scale.  More at The Washington Post.

The boulder that trapped Aron Ralston's wrist

I remember being very impressed by Tom Brokaw's two-hour television documentary about Aron Ralston back in 2005, and somewhat disappointed by the subsequent 127 Hours movie.  It is certainly a remarkable cautionary tale, worth sharing with any of your friends/family who don't share with others their plans for hiking or travel.

A dead robin as a good-luck symbol

As reported by Collector's Weekly:

“The Victorians... liked to send out cards with dead birds on them, robins in particular, which related to ancient customs and legends. There’s a famous quotation from the Venerable Bede about a sparrow flying through the hall of a castle while the nobility is celebrating Christmas: The moment from when it enters until it flies out is very brief, a metaphor for how quickly our lives pass.” Apparently, killing a wren or robin was once a good-luck ritual performed in late December, and during the late 19th century, cards featuring the bodies of these birds were sent to offer good luck in the New Year."

Via Madame Jujujive's always-something-interesting Everlasting Blort.

See also: Piebald robin

Unutterably sad

"A Bolivian lake that was once an oasis of natural beauty full of thriving wildlife has become a waterless basin full of plastic waste. Lake Uru Uru in western Bolivia is covered in mountains of rubbish including plastic bottles and other man-made garbage for as far as the eye can see. The piles of rubbish are believed to have come from the nearby city of Oruro via the Roso Canal, where residents dump their waste. The lake's water is tinged black and brown because heavy metals such as cadmium, zinc, and arsenic have leached from nearby mines into the reservoir. Limber Sanchez, an ecologist with the regional Ecological Centre and Andean People (CEPA), said materials leached from the San Jose Mine had destroyed the purity of the water. He said: 'Alongside the plastic is also the impact the acidic water from mining that has come from the San Jose Mine that almost 365 days of the year empties directly into our Lake Uru Uru.' Sanchez said Uru Uru was hit with a deadly combination of urban contamination, mining contamination, and climate change, which as caused the lake to shrink."

The St. Vincent volcanic eruption

The white band in the middle is water vapor, explained in the discussion thread at the via.

The physics of a cantilever bridge, illustrated

A historical demonstration in 1887 showing the weight of the central span of a bridge being transmitted to the banks through diamond shaped supports. The central "weight" is Kaichi Watanabe, one of the first Japanese engineers who came to study in the UK. Sir John Fowler and Benjamin Baker of Imperial College, who designed the Firth of Forth bridge, provide the supports.

The weight is carried through compression in the wood poles and tension in the arms. The heavy supports on each end prevent the people from tipping inward, and the symmetry of the design cancels out all horizontal components of the loads. The wikipedia page for this bridge and general cantilever bridges have some explanations as well.

Quote from the discussion thread at the via.

How long would it be before someone found your dead body?

In Norway it took nine years - for a man who died in his apartment.

The man, who was in his 60s, had been married more than once and also had children, according to the state broadcaster NRK.

But according to neighbours he kept himself to himself and when they didn’t see him they thought he had moved or been taken to an institution. He was found only when the caretaker requested police open the apartment so he could carry out maintenance work.

Police believe the man died in April 2011, based on a carton of milk and a letter that were found in his apartment. An autopsy showed he died of natural causes. His pension was stopped in 2018 when the Norwegian Labour and Welfare Administration (NAV) could not get in touch with him but his bills continued to be paid automatically from his bank account.

God destroys a tree

Screencap from an impressive gif posted by the US National Weather Service in Green Bay, Wisconsin.  

This is so accurate...

Via Neatorama.

World's longest fingernails get trimmed

Martian skating rink

Photo from the European Space Agency's Mars Express mission, showing water ice inside Korolev, an impact crater on Mars.

Korolev crater is 82 kilometres across and found in the northern lowlands of Mars, just south of a large patch of dune-filled terrain that encircles part of the planet’s northern polar cap (known as Olympia Undae). It is an especially well-preserved example of a martian crater and is filled not by snow but ice, with its centre hosting a mound of water ice some 1.8 kilometres thick all year round.

The very deepest parts of Korolev crater, those containing ice, act as a natural cold trap: the air moving over the deposit of ice cools down and sinks, creating a layer of cold air that sits directly above the ice itself.

Mars' polar caps have a mixture of carbon dioxide ice and water ice, "which vary greatly in proportion to one another depending on the season."

Stuff like this continues to boggle my old man's mind, because when I was growing up, water was considered to be rare in the universe and one of the factors that made life on Earth possible and "unique."

This is a crinkle crankle wall - updated

"A crinkle crankle wall, also known as a crinkum crankum, serpentine, ribbon or wavy wall, is an unusual type of garden wall built in a serpentine pattern with alternating curves.

The crinkle crankle wall economizes on bricks, despite its sinuous configuration, because it can be made just one brick thin. If a wall this thin were to be made in a straight line, without buttresses, it would easily topple over. The alternate convex and concave curves in the wall provide stability and help it to resist lateral forces.
 
"Crinkle crankle" is an ablaut reduplication, defined as something with bends and turns, first attested in 1598 (though "crinkle" and "crankle" have somewhat longer histories). However, it was not until the 18th century that the term began to be applied to wavy walls. At that time these garden walls were usually aligned east-west, so that one side faced south to catch the warming sun and were historically used for growing fruit...
 
Thomas Jefferson (1743–1826) incorporated so-called serpentine walls into the architecture of the University of Virginia, which he founded. Flanking both sides of its landmark rotunda and extending down the length of the lawn are ten pavilions, each with its own walled garden separated by crinkle crankle walls. Although some authorities claim Jefferson invented this design, he was merely adapting a well-established English style of construction. A university document in his own hand shows how he calculated the savings and combined aesthetics with utility." [below, via] 

Related:  Worm fence (snake fence)

Reposted from last year to add this photo of an ancient Egyptian wall:

And this is a Dutch Slingermuur:

Remembering the streetcars of Minneapolis

The fascinating photo above shows a streetcar in the town where I grew up (Excelsior, Minnesota).  Close examination of this photo [click for superhuge size] from the early 1900s reveals horse-drawn vehicles and a gloriously muddy street, crossed by boardwalks (note the sidewalks are also built of boards*).

A hun­dred years ago, you could get from Minneapolis to Excelsior as quick­ly as that 18-mile trip takes today at rush hour — about 45 min­utes — but in­stead of fum­ing in grid­lock, you'd breeze along, gaz­ing at fields and trees from a street­car.

From the late 1800s to the 1930s, streetcars were the pri­mary mode of trav­el with­in Minneapolis and St. Paul, but also east to Stillwater, Bayport and White Bear Lake and west to Lake Minnetonka.

In the late 19th cen­tu­ry, Thomas Low­ry, own­er of Twin City Rapid Transit, be­gan lay­ing tracks for e­lec­tric streetcars to re­place steam-pow­ered com­mut­er trains. At its peak, the com­pany had 524 miles of track and car­ried 200 mil­lion rid­ers each year — more than twice Metro Transit's total rid­er­ship in 2019.

Streetcars brought to­gether peo­ple of all socio­eco­no­mic class­es, said John Diers, co-au­thor with Aaron Isaacs of Twin Cities by Trol­ley: The Street­car Era in Minneapolis and St. Paul. "Ev­er­y­one rode the street­car — from mil­lion­aires to ho­bos," said Diers, a re­tired trans­it employee...

Street­car speeds could top 60 mph, about 20 mph fast­er than a Ford Mod­el T.

As auto­mo­bile mass pro­duc­tion grew in the 1920s and '30s, street­car rid­er­ship dwin­dled. The Lake Minnetonka line closed in 1932. Car sales boomed af­ter World War II, sub­urbs de­vel­oped, and the last street­car in the met­ro area ran in 1954.

Here is a lengthy video of these streetcars (I'm not sure why it autostarts in the middle - you'll need to back up using the video progress bar):

Readers living in or visiting Minnesota who are interested in this subject should consider visiting the Minnesota Streetcar Museum.

*Unrelated to the streetcar, but I'll mention that I used to subscribe to coinshooting and metal-detecting magazines and read that when boardwalk sidewalks were replaced with concrete ones in the 1950s-60s, those doing so found lots of old coins on the ground below the boards.  

The average length of an erect human penis

"Most men believe that the average length of an erect penis is greater than 6 inches (15.24 cm). This belief is due, in part, to several often-cited studies that relied on self-reported measurements, with means of about 6.2 inches (15.75 cm) for heterosexual men and even greater for gay men. These studies suffered from both volunteer bias and social desirability bias. In this review, the combined mean for 10 studies in which researchers took measurements of erect penises was 5.36 inches (13.61 cm; n = 1,629). For 21 studies in which researchers measured stretched penises, the mean was approximately 5.11 inches (12.98 cm; n = 13,719). Based on these studies, the average length of an erect penis is between 5.1 and 5.5 inches (12.95-13.97 cm), but after taking volunteer bias into account, it is probably toward the lower end of this range. Studies show that a majority of men wish they were larger, with some choosing penile lengthening surgery. These surgeries are considered by the American Urological Association to be risky. Most men seeking surgery have normal sized penises. Counseling with factual information about penis size might be effective in alleviating concerns for the majority of men who worry about having a small penis."

Abstract posted at the NIH's National Library of Medicine.

Strange landform on Mars

It's pretty obvious what it is.  The feature rises prominently above the Martian terrain.  Because it is located south of Ascraeus Mons - a large volcano within the Tharsis volcanic plateau on Mars - NASA scientists believe it was formed by volcanic processes.

But you know, and I know, that this is a geoglyph, proving that ancient Martians worshipped rubber duckies.

More information at NASA's Mars Exploration Program.