The mystery of the magnetic train

This past week, thanks to Laughing Squid and other sources, a lot of people watched and were amazed by this simple demonstration of electromagnetism in action.

It is billed as the “world’s simplest electric train,” and it is almost certainly the case.  Using only a battery, some strong magnets and some (bare) coiled copper wire, one can make the “train” travel numerous circuits through the copper “track,” until the battery is completely drained.

This caught my attention because it is a very clever twist on one of Michael Faraday’s original discoveries!  Not electromagnetic induction, as I reflexively thought, but a homopolar motor.  Below is an animation of such a motor that I whipped up in my office.

A simple homopolar motor.

A simple homopolar motor.  Just in case you don’t believe it actually works, a longer video is here.

This particular homopolar motor design is ridiculously simple: a pair of neodymium magnets are stuck (by magnetic force only) to the bottom of an AA battery. A wire loop is balanced on the top of the battery, bent so that it touches the magnets on the bottom.  When the connection is made, the wire will start to spin immediately, and will in general start spinning so fast that it will flip itself off of its perch.  More sophisticated and stable designs exist, but this one is quick and showy.

So how does the homopolar motor work, and the “magneto-electric” train shown in the video?  Both of them depend on the relationship between moving electric charges and magnetism, albeit in somewhat different ways.

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Ann Gregory, RIP (1974-2014)

One of the joys of twitter is getting to meet so many kind, interesting, and varied people from places all over the world and getting to share, at least a little, in their lives.  One of my favorite of these people was Ann Gregory, who passed away on November 26 from cancer-related complications.  Ann was one of my earliest twitter followers, and therefore one of my oldest twitter friends.

I can’t say that I knew Ann particularly well, as our interactions were unfortunately limited to twitter.  She was already a cancer survivor when I met her, but she was always unfailingly kind and fun to talk to, and chatting with her always cheered me up no matter what the situation.  We shared a love of cats, and would share photos of our cute kitties now and again.

Her cancer came back suddenly and unexpectedly, and it was a shock to me how quickly it took her life.  My thoughts and sympathies go out to her husband Chris and her family and friends.  Ann kept a long-running blog describing her life and illness, and her husband wrote a very touching post after her passing, both in memory of her and as a message to those still coping with their own difficult cancer diagnoses.  To just borrow one paragraph from it,

When Ann was diagnosed all those many years ago at 32, she would say to me, “I just want to live to my 40th birthday”.  Well, we did and could we have done anything better?  Sure.  But we didn’t live life like it was going to end on a schedule.  We lived it like everyone else does – one day at a time focused on what you need to to stay ‘normal’ when you have been touched by cancer.

The internet, and the world in general, feels somewhat empty to me with her gone.  She was a nice friend and I will miss her and remember her.

Rest in peace, Ann.


Ann’s obituary can be read at The Advocate.  As noted there, donations in her memory can be made to the M.D. Anderson Cancer Center.

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Slurstorm, and the flaws in “Shirtstorm” arguments

I hate writing posts like this.  I prefer to write about fun physics, history of science and cool horror fiction.  But some things are so appalling and disgusting that one must speak up, especially if one’s friends are attacked.

You probably already know the story.  I’m not going to directly use the names of the central victims in this post, as they’ve already been plastered all over the place, and I don’t feel like adding one more link to the pile.

In short: on the 12th of November, the Philae lander detached from the Rosetta spacecraft, landing on the surface of Comet 67P in the first ever controlled landing on a comet surface.  It was a remarkable achievement, and everyone involved was elated — everyone watching, including me, was similarly thrilled.  But the event was marred when the Project Scientist appeared on camera wearing a gaudy bowling shirt plastered with scantily clad women in a variety of poses.  He also made a comment about the mission that many felt was inappropriate: “She is sexy, but I never said she is easy.”

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The Elementals, by Michael McDowell

Michael McDowell’s reprinted 1981 novel The Elementals conclusively answers a question that I’ve been wondering for years: why are there so few classic haunted house stories?  I’ve always been a fan of such stories, or more generally “old dark house” stories, as Orrin Grey refers to them in the introduction to Benighted.  However, until recently I could only think of a handful of truly classic ones at most, such as Shirley Jackson’s The Haunting of Hill House (1959), Richard Matheson’s Hell House (1971), and of course Stephen King’s The Shining (1977).

The answer to my question?  It turns out that many great “old dark house” stories, like the houses featured in them, have been lingering in obscurity, unattended to, dark and silent, waiting for someone to come along and uncover their secrets.  Valancourt Books has done an admirable job bringing many of these stories to light recently; I have spoken fondly in the past about Jack Cady’s The Well (1980), and I have now been blown away by The Elementals.


The novel begins at the funeral of Marian Savage, the matriarch of the venerable southern Savage family.  After the ceremony — which includes an unscheduled, bizarre and horrifying interlude — the Savage and McCray branches of the family decide to head down to the Alabama coast for the summer, to the remote and aging refuge of Beldame.  There, three Victorian houses stand: one each for the Savage and McCray families, and a third that is abandoned and slowly being consumed by a massive sand dune.  Nobody knows, or seemingly ever knew, who owns that third house.

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No Songs for the Stars, by Mary SanGiovanni

I’m rather intrigued these days by the concept of chapbooks, short typically inexpensive books that first became popularized in the 17th and 18th centuries.  I guess they never really went away, but recently I’ve been seeing — or noticing — more of them being printed.  The first one I picked up was Corley and Grey’s charming Gardinel’s Real Estate, and very soon afterwards I saw a tweet about No Songs for the Stars, by Mary SanGiovanni.

Published by White Noise Press, it comes in an elegant envelope.

Published by White Noise Press, it comes in an elegant envelope.

In this blend of noir and cosmic horror, the Sulphur City Police have finally captured a serial murderer of children.  Under interrogation, the killer cryptically tells the police to “Check the wall,” and explains how he has received messages from beyond on it, telling him to… do things.  Though most of the department dismisses these statements as the ravings of a lunatic, Lieutenant Gina Maldonado is curious enough to investigate — and she will uncover the horrible secret within the walls.

No Songs for the Stars is an elegant story, well-written and compelling.  It is only 20 pages long, as one would expect for a chapbook, but also like most chapbooks it is a beautiful printing that includes an excellent cover and eerie interior illustration.

As I noted about Gardinel’s Real Estate, the mixture of art and literature in chapbooks is really quite effective and is reminiscent of the older magazine tradition of illustrating all their stories, such as those I recently dug up for my Halloween Treats.  I’m going to have to snoop around for more chapbooks in the future!

I’m also going to have to snoop around for more of Mary SanGiovanni’s writing, as this is the first piece I’ve had the chance to read! No Songs for the Stars is an excellent, atmospheric tale.

Update: I should also note that, like most chapbooks, it is a limited edition signed printing.  Only 150 were printed, though at the time of posting it seems that some are still available for purchase.

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The Great Sausage Duel of 1865

(Tip o’ the hat to Blake Stacey for first pointing this story out to me!)

The history of science is filled with macabre tales of self-experimentation, amoral experimentation on others, horrific accidents, and even mysterious and sinister disappearances. Perhaps the most unusual tale I’ve come across, however, involves an alleged duel — not with swords or guns, but with sausages.

"Choose your weapon, sir."  German Bratwurste, via Wikipedia.

“Choose your weapon, sir.” German Bratwurste, via Wikipedia.

The opponents in this duel are as incongruous as the choice of weapons.  On one side, we have the formidable Otto von Bismarck (1815-1898), the Minister President of Prussia, appointed by and second only to the King himself.  On the other side, we have the energetic, clever and contradictory scientist and politician Rudolf Virchow (1821-1902), leader of the Progressive Party in the Prussian legislature (Landtag).

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Posted in ... the Hell?, History of science | 9 Comments

Halloween Treats 2014

(Update: It cost me a good deal of my sanity, but I think I fixed “The Monkey’s Paw” pdf to load quickly in browser.)

It’s that time again to post a collection of “Halloween Treats”: classic ghost and horror stories to be read in the dark of night!  I’ve been doing this since 2007, and you can read the old editions here:   2007200820092011, 2012 and my 2010 post on the true story of the “Lady of the Lake“. It is likely that not all of the links in those old posts work, but the lists are there.

As a special treat: I tracked down, whenever possible, pdfs of the original publications!  Many of them include excellent illustrations, a tradition that I would like to see return in horror.

This year’s selections:

The Monkey’s Paw, W.W. Jacobs (1902).  Somehow I’ve never included this classic tale of wishes gone awry in my posts! Though it is so well-known as to seem clichéd, it is a story of surprisingly subtlety.  Note, in particular, the sergeant-major’s terse and unsettling description of the paw’s history.

Lot No. 249, A. Conan Doyle (1892).  Best known for his stories of Sherlock Holmes, Doyle also wrote a number of potent horror stories.  In Lot No. 249, a tale of an Egyptian mummy takes on a particularly diabolical twist.  If you want to see the pictures in a good quality, check out this link!

Canon Alberic’s Scrapbook, M.R. James (1895).  A story by an undisputed master of ghost stories, M.R. James! In this tale, the Englishman Dennistoun happens across — and purchases — and old scrapbook from a local Frenchman.  Oddly, however, the man knowingly sells the book well below its value, despite Dennistoun’s good-natured offer to give more.  Dennistoun soon learns that his new acquisition comes with a rather unpleasant passenger…

The Haunted and the Haunters: Or the House and the Brain, by Edward Bulwer-Lytton (1859).  Bulwer-Lytton is most remembered today for his ridiculously dramatic prose, such as “It was a dark and stormy night…”  As I have noted on this blog before, however, he was a very effective author at times.  The Haunted and the Haunters is considered one of the best haunted house stories of all time, and it contains a rather bizarre epilogue.

Shiva, Open Your Eye, by Laird Barron (2001).  I’m a huge fan of Laird Barron’s work, and I consider him one of the best authors of horror working today.  A few of his stories are freely available to read online, including Shiva, Open Your Eye.  In this story, a government man comes poking around on a farm in Eastern Washington state.  What he finds at the farm, and within the barn in particular, is more than he bargained for, or could even comprehend.

The Undying Thing, by Barry Pain (1901).  Sir Edric’s crimes bring a curse down on his family, and his second wife gives birth to a monstrous child.  Decades later, the monstrous offspring returns from the wild to end the lineage.

Huguenin’s Wife, by M.P. Shiel (1895).  M.P. Shiel wrote a number of classic stories of the weird and horrific, including the apocalyptic novel The Purple Cloud.  In Huguenin’s Wife, the narrator is desperately summoned by his friend Huguenin to his home on a secluded Greek isle.  Huguenin’s wife has died, but she may not have been human to begin with.

Luella Miller, by Mary E. Wilkins-Freeman (1902).  Wilkins-Freeman is one of the greatest writers of ghost and horror stories of all time.  In Luella Miller, she tells the story of a vampire of a subtle but still deadly nature.

Enjoy the stories, and Happy Halloween!

Don't get caught by a mummy! From "Lot No. 249."  (source)

Don’t get caught by a mummy! From “Lot No. 249.” (source)

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