Piddock - and an appendix

click to enlarge

A week ago, in the RD&E hospital, Exeter, I was looking at a very nice photo-presentation in the corridor to the Lowman Ward - Tracing the River Lym, by Roger Polley and John Woodman - about the River Lym (or Lim) that flows to the sea at Lyme Regis. It features photo prints spliced together to make panoramic views of the Lym from its mouth in Lyme Regis right up to its source near Cannington Viaduct, Uplyme.

One very interesting detail in the accompanying text (left) by Dr Collin Dawes was the reference to the Romans and a rock-boring mollusc, the piddock (Pholas dactylus). The piddock is of mixed value: it apparently makes good eating (I'll take that on trust, as I can't stand shellfish) but contributes to coastal erosion due to its mechanically boring into soft rock to make the hole where it lives to filter-feed. However, Pliny the Elder, in his Natural History, mentioned a remarkable property of the piddock:

LXXXVII. Concharum e genere sunt dactyli, ab humanorum unguium similitudine appellati. his natura in tenebris remoto lumine alio fulgere claro, et quanto magis umorem habeant lucere in ore mandentium, lucere in manibus atque etiam in solo ac veste decidentibus guttis, ut procul dubio pateat suci illam naturam esse quam miraremur etiam in corpore.

LXXXVII. The class shellfish includes the piddock. The piddock, named finger-mussel from its resemblance to a human finger-nail. It is the nature of these fish to shine in darkness with a bright light when other light is removed, and in proportion to their amount of moisture to glitter both in the mouth of persons masticating them and in their hands, and even on the floor and on their clothes when drops fall from them, making it clear beyond all doubt that their juice possesses a property that we should marvel at even in a solid object.

- Pliny: Natural History, Volume III, trans. H Rackham, Heinemann / Harvard University Press, Loeb edition (Internet Archive plinynaturalhist017760mbp)

According to this and other accounts, this bioluminescent effect is extremely strong: a number of researchers have studied the effect historically; see, for instance, page 162 of The Edible Mollusks of Great Britain (MS Lovell, 1867.  J Beccaria found that a single piddock "rendered seven ounces of milk so luminous that faces might be distinguished by it", and another researcher, Costa, wrote that "if the flesh is chewed and held in the mouth, the breath becomes luminous and looks like a real flame".

The presentation went on to describe the work of Jan and Robert Knight of Knight Scientific, Plymouth, in elucidating the role of the photoprotein involved, pholasin (aka Pholas luciferin), and its use as a diagnostic assay for white blood cells, antioxidants and free radicals. Essentially it enables the detection of inflammation before it becomes symptomatic. (The Knights featured on the BBC's now-defunct QED science documentary series in 1993). Interesting stuff.

Appendix:  12th January 2012. Five years after posting this, I just had an interesting e-mail discussion with Dr Andrew May, a volunteer at Lyme Regis Museum. and the maintainer of the Lyme Regis Museum blog. Andrew asked about a detail in the original version of this post, which said the piddock shells had been found at the site of a Roman villa by the River Lym. Unfortunately my weblog was the only source findable for this detail.

My first suspicion was that I'd misread Dr Dawes' account, so I took a quick detour on the way home today and rechecked (the presentation is still on the wall in the RD&E). Sure enough, it doesn't say what I cited: it says "thousands of shells" were found at the villa site (the Holcombe site where the Holcombe Mirror was found in 1970) and then goes on to discuss piddock without explicitly making the connection. I'd misread, and conflated the details. I took down the blog post and apologised for the wild goose chase I'd started.

However, very good news. Andrew also investigated the story, and checked with the Devon Historic Environment Service (the site, although near Lyme Regis, is just inside the Devon border). They sent him the mollusca report for the Holcombe dig (i.e. what was found in the shell midden near the bath house area of the villa), as published in Devon Archaeological Society, Proceedings, No 32, 1974. Among land snails and other marine species (like Crassus in the movie Spartacus, the Roman occupants liked both snails and oysters), the dig did indeed find shells of the common piddock, Pholas dactylus.

Andrew and I both have our story! I've updated and reinstated the post.

The Devon Historic Environment Record is quite enlightening to read; the Victorian era took rather a different view of archaeological conservation. In the mid-1800s, Roman mosaics were discovered at the Holcombe site. The record says:

Reference to two mosaics, one bought at auction in 1854 and given to Exeter Museum; and one bought on 05/04/1860 and relaid in his house "The Chancel", Sidmouth. ... Hutchinson, P. O. 1848-1894)

This is the Sidmouth historian Peter Orlando Hutchinson. The idea of a local historian buying up archaeological remains and using them for home decoration is quite astonishing to the modern mindset.

Appendix 2: a spot of geeky medical explanation. This piddock topic was, unfortunately, hard-gained. I had more spare time than I wanted, to read the RD&E wall posters over Christmas 2007, due to keeling over with appendicitis late on Christmas Eve and having an appendectomy in the small hours on Christmas Day.

The story, should it interest/edify anyone: I'd been a bit unwell with intermittent stomach pains and bloating for about three months; I was feeling pretty low with it, as the source was unidentifiable, and nothing seemed to help. There seemed to be a vague correlation with heavy meals and fatty foods, and my GP had been working through possibilities such as peptic ulcer, gallstones, whatever. On Christmas Eve, however, the pain become continuous and over the day shifted to lower right. On the evening of Christmas Eve it was bad enough that we took a taxi to the RD&E drop-in centre, where they prodded McBurney's point, and from my reaction instantly diagnosed appendicitis, near-rupture it turned out, and I was in theatre within a couple of hours. So no Christmas festivities, unless you count some of the team that wheeled me in wearing antler hats.

Once I was over the surgery, the pain and bloating stopped, and have never come back. Clearly the appendix was the problem all along. The history's morbidly interesting in hindsight. I don't blame anyone for not spotting it earlier, as early appendicitis is hard to diagnose, especially with the rather vaguer clinical course of the "suppurative" form I had. I'm in the wrong age group anyway (the peak for appendicitis is late teens), and only around 50% of cases manifest in the classic symptoms. Plus the bowel is bad at localising pain; the appendix is served in a general sort of way by a nerve that joins the spinal cord at the T10 vertebra, which gives a generalised mid-belly pain. You only get lower-right pain when the infection worsens and surrounding structures become irritated (hence the classic move of the focus of pain with appendicitis).

Puzzles and peculiarities for Christmas 2007

It'll appear on the Guardian website shortly, but if you want a sneak preview, here is this year's General Knowledge Paper (PDF, aka the King William's Quiz) set for students of King William's College, Isle of Man. It's considerably easier with Google to hand, but some make it a point of honour not to use it, and some questions are sufficiently unspecific to be unGoogleable unless you twig the common factor for the section.
Check out also PuzzleMaster, the site for Chris Maslanka, who writes the long-running Pyrgic Puzzles page for Guardian Weekend. It includes archives from Radio 4's Puzzle Panel and Chris's Sydney Mind Olympics, a set of Australian-themed problems that ran in parallel with the 2000 Olympic Games.
Or for a slightly alternative format, also from the Guardian, try the Charlie Brooker festive quiz.

In a different vein, if you want some interesting reading, have a look at Anne T-V's link page for BMJ Christmas issues. Every year, the British Medical Journal publishes a selection of quirky articles. As explained in the editorial for 2000, A pile of strangeness, "The essence of the Christmas BMJ is strangeness. It's our left brain issue. We want everything to be not as it seems." This involves some spoof articles, but also fascinating studies of real but unusual topics: Civilisation and the colon: constipation as the "disease of diseases" (the fairly bizarre history of a malady and its mistreatment), Death and miasma in Victorian London: an obstinate belief (a history of the long-standing belief in disease being caused by, essentially, smelly air), Sword swallowing and its side effects (self-explanatory), White coats and fingerprints: diagnostic reasoning in medicine and investigative methods of fictional detectives, the excruciating You're not going to give me the umbrella, are you? (the persistence of a vivid myth among patients), and a historical murder mystery, The mysterious death of Francesco I de' Medici and Bianca Cappello: an arsenic murder?. So, if you like seasonal but mildly morbid stories, check out Ann T-V's page, which links handily to the contents pages back to 1995. - Ray

Mountweazels and other fictions

A old article I just ran into in the New Yorker: Not a word, the interesting story of Lillian Virginia Mountweazel, an American fountain designer turned photographer who died prematurely in an explosion while on assignment for Combustibles magazine.
      The interesting part is that she didn't exist, but appears in the 1975 New Columbia Encyclopedia as a copyright trap: if her biography turns up in any other reference work, the publishers will know that it has been stolen rather than independently researched. Another example cited is the appearance of a non-word, "esquivalience", in the New Oxford American Dictionary. It's nice to see this phenomenon confirmed, as it has rather an urban myth flavour to it.
      As you can gather from the Wikipedia Mountweazel entry, fictitious entries have varied motives: copyright traps, plain mistakes, hoaxes for fun, and hoaxes for fraud. For instance, the 1880s American Appleton's Cyclopedia of American Biography has around 200 known hoax entries. In this case, the probable motivation was financial; the contributors being paid by space and with checking only for general style, the temptation must have been too great.
      Similar considerations apply to maps. In 1999 this Telegraph article, AA in £20m battle over 'copied' Ordnance maps, reported how the Automobile Association was caught out as having copied from Ordnance Survey maps a number of deliberate stylistic fingerprints - "kinks in rivers, the addition of minor buildings or exaggerated curves in roads". You can find other examples at the OpenStreetMap article Copyright Easter Eggs - Maps that Lye, and confirm using Google Maps that there are definite discrepancies between the street data and aerial photos, such as The Avenue, Finchley, that's displaced to cut straight through a block of flats. As with textual references, it's a matter of opinion whether many of these are deliberately fake "trap streets", simple errata, or time-related errors (such as road layouts revised by subsequent building, or reliably anticipated ones that never came to be). - Ray

Monkey's armpit and other insults

Language Log and Languagehat, both language weblogs of the highest reputation and credentials, report a book just released: Uglier Than a Monkey’s Armpit: Untranslatable insults, put-downs and curses from around the world. It's co-written by Stephen Dodson (who has just come out as the compiler of Languagehat) and Dr Robert Vanderplank (director of the Oxford University Language Centre). Looks fun! - Ray

Dante's world

Another semi-promotional post: Exeter WEA includes in its Spring 2008 listing an interesting-looking course, Dante and his world. Dante puts various contemporary political figures of his time into Hell, and this course, led by Dr Stephen Bemrose, author of A New Life of Dante, explores the various cultural and historical influences that went into the work. "By exploring passages in translation from Dante's Inferno ... this course offers a way into the mediaeval mindset and the turbulent world of Italian politics on the threshold of the Renaissance".

Its journey format and, to most modern readers, the need for a concordance, makes Dante's Inferno ideal text for hypertext representation, and there are a number of excellent Web projects for accessing the text: Digital Dante, the Flash-based Dante's Inferno, a Virtual Tour of Hell and Danteworlds are just some of them.

The potent imagery of Dante's Inferno has been remarkably productive in the works that it has inspired: see Wikipedia's Dante and his Divine Comedy in popular culture, which covers everything from the classic prints by Gustave Doré to the recent animated film version ("apocalyptic graphic novel meets Victorian-era toy theater"). My current film favourite is the 1935 one starring Spencer Tracy, which is completely unmemorable except for the stunning 10-minute Hell sequence by the designer and painter Harry Lachman. See 1935 Dante's Inferno for an update with YouTube links.

Of the literary works it has inspired, one of the best, in my view, is Inferno by Larry Niven and Jerry Pournelle, which throws into Dante's Hell a modern science fiction author who attempts to rationalise it in terms of technology. Mary Pat Campbell's Building a Modern Hell is a good critique of it.

Addendum: Dante's Inferno by Sandow Birk looks interesting. This illustrated edition sticks faithfully to the structure of the original, but translates the text into into modern vernacular English, as well as replacing in-references from Dante's time with present-day equivalents

a literary adaptation incorporating contemporary urban slang and references to contemporary events and people, and unsettlingly vivid illustrations based on Gustave Dore's well-known engravings ... Here, the vision of Hell is full of the familiar scenes of contemporary Los Angeles (with some San Francisco mixed in). The ever watchful police helicopters search the Stygian skies, familiar images of the mythic are assaulted by corporate logos and mass-consumption detritus. The Minotaur guards the shawerma stand of the damned, while Greyon, the Beast of Fraud, is transformed into a pollution-belching SUV.

- Ray

The Gömböc

An interesting mathematical curiosity: the Gömböc (pronounced "gəmbəts"). This is an intriguing object, devised by Hungarian mathematicians Gábor Domokos and Péter Várkonyi, that has the property of self-righting to a single stable position despite being homogeneous, completely convex and not being obviously "flat" or "thin". (That is, this self-righting property is easy to obtain if you allow internal hollows or heavy inserts that skew the weight distribution, as in the Weebles or Balancing Ovoid toys - but not if the object doesn't curve inward, and is solid and the same material all the way through).

As with many other shapes with useful mechanical properties, this self-righting behaviour has already been achieved in nature in animals such as the Indian Star Tortoise. More on this at the Mathematical Intelligencer article Mono-monostatic bodies: the answer to Arnold's question (PDF).

A gömböc is, incidentally, Hungarian for a round thing, which may apply to dumplings or the sinister pork haggis in the Hungarian folktale A kis gömböc that hangs in a cottage attic and eats a family.



Compare the rattleback or celt, an object of no discernable application, but one also with unusual dynamic properties: in its case, a preferred direction of spin.

- Ray