Mounting Microfossils ~ Forams and Glue, Art and Polymaths

In which the blogger exudes enthusiasm for mounting microfossils on slides, and finds, amid the shells and glue, art and polymaths (though he stretches the definition of the latter).

Science and Art

It’s a marriage of science and art.  Mounting the tests or shells of microorganisms on microscope slides is an integral part of safeguarding, organizing, cataloguing, and researching these tiny specimens (generally on the order of half a millimeter or smaller).  But there’s an aesthetic appeal for me in this as well.  Pictured below is a slide on which I’m beginning to categorize some of the foraminifera fossil shells that I’ve found in a sample of Jurassic material (Oxford Clay from Yaxley, England).

Given the gaping holes in my knowledge of these single-celled protozoa and the shells they create, I’m really not sure whether the groups I’m creating are species specific to any degree, or whether I’m simply discriminating among specimens of the same species on the basis of irrelevant physical characteristics or vague traces of the preservation process.  Despite how inchoate this is, I find even this slide to be visually intriguing.

As slides accommodate more and more specimens, their visual appeal can grow markedly.  Case in point – the two slides shown below, prepared by Karl-Otto Bock, contain many shells of recent (not fossils) foraminifera from two locations – a beach at Malia, Crete, Greece (first, very crowded picture) and the ocean floor in the Hebridian Slope in the North Atlantic (second, sparser picture).

(The images of both slides were downloaded from Michael Hesemann’s website of the Foraminifera.eu-Project, and are reproduced under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 Germany License.  The Foraminifera.eu-Project represents the work of scientific amateurs and professionals dedicated to promoting knowledge of, and research about, foraminifera – a rich and very useful site.)

Bock has grouped the foram shells by species on these slides.  How the specimens are arranged within each cell, how many to place in a cell, which species are placed near to each other, where the species with the most bizarre structures are settled, are among the many choices to be made in this process.  Even if Bock gave no thought to the aesthetic effect of the arrangements he’s creating, surely there is one.  And the opportunity for a touch of humor is there – notice the #10 cell in the Crete slide (the first slide) with a foram placed in the 0.  (On the website, clicking on individual cells in a slide brings up information about that species.  Very cool.)

This is painstaking work.  Manipulating the small shells with the fine hairs of a wet brush and positioning and affixing them just so demands a steady hand and an inordinate amount of patience.  There’s luck involved as well given the propensity of the specimens to “jump” if touched with a brush that’s not wet enough.  If one of these escapees manages to end up off the slide and out of the tray in which the slide might be resting, good luck finding it again.

Occupying a special place among mounters of microfossils are Arthur Earland (1866 – 1958) and Edward Heron-Allen (1861 – 1943).  Though amateurs in a strict sense of that term, both men were leading figures for three decades in the study of foraminifera, collaborating on many significant studies.  Among their notable efforts is the study of the foraminifera brought back from Robert Falcon Scott’s star-crossed expedition to Antarctica (1910 – 1912) (Protozoa, Part II.  Foraminifera, British Museum, Volume VI, No. 2, 1922).

Earland, who spent his working life in the Post Office Savings Bank Department, was a “Civil Servant who worked at Forams as a relief from the monotony of his job.”  This is Earland’s own description of himself, if I correctly read his obituary in the Journal of the Royal Microscopical Society, September – November, 1957.  In 1954, he informally estimated that the new foram taxa identified by the Earland/Heron-Allen collaboration included at least 2 families, 1 sub-family, 19 genera, 133 species, and 64 varieties.  The Royal Microscopical Society obituary concludes, "He leaves . . . the reputation of a forthright man of sterling character, the last of the nineteenth century masters of the Foraminifera in Britain."  Perhaps it’s only appropriate that there’s precious little biographical information on the web about this most self-effacing man.

Human Polymath

In contrast, Heron-Allen continues to captivate nearly 70 years after his death.  (The brief portrait of Heron-Allen which follows is based largely on information in R.B. Russell's Short Biography of Edward Heron-Allen appearing on the Heron-Allen Society website, and Edward Heron-Allen:  the Man and his Scientific Library, by Clive Jones which was published in the Winter 2004 issue of Set in Stone, the newsletter of the Palaeontology Department of the Natural History Museum, London.)

Russell asserts that, despite the man's many diverse areas of endeavor, “[r]ather than a dilettante, Heron-Allen is better described as a polymath.”  Heron-Allen trained and worked, at times, as a lawyer, but that was the least of it.  His scientific work, including his collaborations with Earland, was so highly regarded that he was elected in 1919 to the Royal Society.  He also apprenticed himself to one of the period’s foremost violin makers, made violins, and wrote extensively on them.  Among his books was the popular Violin-Making:  As It Was and Is (1914).  He also studied languages, publishing several translations of Persian literary works, including one of The Rubaiyat of Omar Kahyyam.  In the 1880s, Heron-Allen dedicated himself to palmistry or cheirosophy (also spelled chiromancy).  On this, too, he published successfully and then undertook a triumphal tour of the United States.

He turned to fiction; among his novels was a light romantic novel which he titled The Romance of a Quiet Watering-Place (Being the Unpremeditated Confessions of a not altogether frivolous Girl) and published in 1888 under the pseudonym Nora Helen Warddel (an anagram of his name).  Later, as Christopher Blayre, he wrote tales of the supernatural, such as The Purple Sapphire.

I would note that, perhaps for good reason, The Purple Sapphire, which is tale of a cursed gem stone purloined from a Hindu statue during the Indian mutiny in the 1850s, has the ring of truth to it.  The website of the Natural History Museum describes (7th slide at this link) a purple sapphire in its collection, and on display in its “vault,” as having been looted during the Indian mutiny and associated with misfortune for all of its owners since.  According to NHM, the sapphire’s final owner, Edward Heron-Allen, deemed it cursed and locked it away in an bank.  After his death, his daughter gave it to the NHM.  An appropriate dénouement, given that in the short story, the stone’s final resting place is the museum at the fictitious University of Cosmopoli.

One special aspect of the Earland and Heron-Allen collaboration was their Christmas slides.  Giles Miller, the NHM Curator of Micropalaeontology, describes in a post (Microfossil Christmas Cards) on his always fascinating blog that, at Christmastime, Earland and Heron-Allen exchanged microscope slides on which they had mounted foraminifera fossils.  The practice continued until the early 1930s when their friendship ended.  Pictured below is a slide from Christmas, 1912.

Simply amazing.  Clearly written in forams is “AE XMAS 1912.”  When I first saw the photograph of this slide, I was stunned first by the startling realization that these men had beautiful fossil foram tests in such abundance that they could indulge in this activity, and then by the time and patience required to render this piece of art.

Not shown in the photograph are the handwritten notes on the slide:  “Xmas 1912” and “Prosit!  AE.”  (They can been seen at this link at the NHM.)  I believe this particular slide was a gift from Earland to Heron-Allen.  The picture is copyrighted by The Natural History Museum, London, and is used with permission.

Botanical Polymath

But Heron-Allen isn’t the only polymath I have stumbled upon as I pursue my interest in mounting microfossils on slides.   I have found what I can only term a botanical polymath - gum tragacanth.  The adhesive I use to affix microfossils to slides is a solution of water and gum tragacanth.  When I began to work with microfossils on my own, I followed the lead of paleobiologists Howard Armstrong and Martin Brasier who, in their Microfossils (2nd edition, 2005) advise,

Adhesion of microfossils is improved by brushing the slide’s surface beforehand with a weak solution of Gum Tragacanth to which a drop of Clove Oil has been added (to reduce fungal growth).  (p. 279)

When the gum tragacanth solution dries on the slide, it is ready to receive individual microfossils.  Transferring a fossil to the slide with a slightly wet brush activates the water-soluble glue which will hold the fossil in place when it dries.  Of course, being water-soluble, the glue easily releases the microfossil when moistened.  Whether the clove oil will actually retard fungal growth remains to be seen, but there’s a delightful scent released as my wet brush touches the dried solution.

Over the years, many different adhesives have been suggested for microfossils, but the gum tragacanth solution appears to have remained among the favorites, cited often in books and articles describing working with microscopes to view microorganisms.  For instance, in 1922, Arthur Earland wrote

The best fixative for mounting is gum tragacanth, which is almost invisible when dry, being quite devoid of the objectionable glaze which characterizes gum arabic.  It is also much less subject to variations of moisture than gum arabic which alternately contracts and expands with changes of weather and often fractures delicate forms.  Powdered gum tragacanth should be used in the preparation of mucilage.  (Collecting and Preparing Foraminifera, in Modern Microscopy:  A Handbook for Beginners and Students, edited by M.I. Cross et. al., p. 263.)

Still earlier, in 1859, William Lowndes Notcutt recommended that opaque objects, which required the focusing of an external light source, be mounted on blackened slides with “mucilage of tragacanth, also previously mixed with black.”  (A Handbook of the Microscope and Microscopic Objects, p. 28)

Gum tragacanth is the dried sap from Astragalus gummifer, a plant known by various common names such as goat’s-thorn and tragacanth milk-vetch.  The plant is a small, thorny, evergreen shrub, native to the semiarid grasslands and dry mountainous areas of Western Asia, including Iran, Lebanon, Syria, and Turkey.

This illustration is taken from Medicinal Plants, Being Descriptions With Original Figures of the Principal Plants Employed in Medicine and An Account of the Characters, Properties, and Uses of Their Parts and Products of Medicinal Value, by Robert Bentley and Henry Trimen, Volume II, 1880, entry 73.

Gum tragacanth has a extensive history, having been described, according to biochemist Amos Nussinovitch, at least as early as 300 years before the beginning of the Common Era.  (Plant Gum Exudates of the World, 2009, p. 55.)  It has long been part of Materia Medica, the study of pharmaceutical chemistry, particularly those substances derived from plants.

Bentley and Trimen describe how the gum naturally emanates from breaks in the plant’s stem, in a flow likened by one authority they cite to a “worm.”  The harvesting of quality gum tragacanth involves digging around the base of the stem, making an incision, and collecting and drying the gum that streams from that cut.  If properly prepared, the material collected from these incisions dries in white flakes.

Chemically, the gum is an edible, complex, acidic polysaccharide.  Agricultural biochemist Mark Dreher explains that

Tragacanth is composed of a mixture of polysaccharides:  traganthic acid, a water-insoluble component, which confers water-swelling properties to the gum; and arabinogalactan, a water-soluble polymer that gives the gum solubility.  (Food Sources and Uses of Dietary Fiber in Complex Carbohydrates, edited by Susan Sungsoo Cho, et al., 1999, p. 347.)

In solution, it is very viscous or gel-like.

Gum tragacanth has been exploited for centuries for its thickening, binding, water absorbing, and stabilizing attributes.  It is incredibly versatile; I learn of new uses in nearly every additional source I consult.  At the same time, the volatility of the part of the world from which it originates, has led to the search for alternatives.  (I must also admit that I don't know if other plant gums, such as gum arabic, are equally versatile.)

Here, then, are just some of the applications of gum tragacanth.  It has been added to many, many foods, including salad dressings, sauces and gravies, ice cream, sherbet, chocolate milk, processed cheese and cheese spread, syrups, catsup, and candy, particularly chewy candies.

[Later edit:  With the passing of superstorm Sandy along the east coast of the U.S., I was finally able to wander the aisles of my local grocery store and gauge the extent to which alternatives have displaced gum tragacanth in foods.  Apparently, it's been a thorough overthrow.  I discovered no mention of gum tragacanth for foods in which it might have been used in the past.  Xanthan gum appears fairly frequently, a gum that offers a fascinating story on its own, being the byproduct of a fermentation process involving certain strains of bacteria.]

Beyond food, gum tragacanth has been used as a laboratory culture medium; a digestive tract stimulant, treating both diarrhea and constipation; a treatment for tumors; burn dressings; a thickener for textile dyes, ink, water colors; a binder in paper manufacture; and, of course, glue (including the sealer for the final, outermost leaf in cigars).  It is also added to toothpaste, lotions, denture paste, and spermicidal jellies.  Given the last application, it’s probably appropriate that, for millennia, it has also been considered an aphrodisiac.

I must mention one final use of gum tragacanth.  Edward Heron-Allen noted, in Violin-Making:  As It Was And Is, that the gum has been an ingredient in the varnish applied to violins.

Interesting where forams and glue may take you.


Sources Used But Not Specifically Cited in This Post

David Julian McClements, Food Emulsions:  Principles, Practices, and Techniques, 2004.

Rebecca Johnson and Steven Foster, National Geographic Desk Reference to Nature’s Medicine, 2008.

Entry for Astragalus gummifer on the website of Plants For A Future.

Entry for A. gummifer on the Ecocrop website of the UN’s Food and Agriculture Organization.

Entry for A. gummifer on the U.S. Department of Agriculture’s Germplasm Resources Information Network website.

Entry for tragacanth on the WebMD website.

Lingering Around and Shaking Things Up

An October week’s retreat to my summer cottage on the North Fork of Long Island, New York, shifted a small portion of my paleontological world.

It began when I went biking in the middle of the week and became convinced that, with the falling temperatures of the previous night, had come an invasion of body snatchers.  An invasion from Mr. Roger’s Planet.  Everyone I passed – jogger, biker, walker – old, young, middling – greeted me with a robust “Hello, neighbor!”  Well, more like “Hey,” “Hi,” “Hello,” “Morning.”  What had happened to the summer’s many pointed rejections of my overtures?  Had something transformed these aggressively isolated Homo sapiens into a community of greeters (and possibly huggers)?  I wondered if the coming of fall, and particularly the first cold snap, had signaled subliminally to the locals that anyone out and about now was one of them.  The summer invaders had, at long last, all gone home.  But little did they know that I was a lingerer, someone left over from those summer days.

I was still contemplating whether I had been enjoying a wave of overt friendliness under false pretenses when I parked my bike in the sand and went in search of shells.  I walked along one of the beaches that line the bays that separate the North and South Forks of this eastern end of the island.  The twin forks are shown in the map below, separated by various bays, Great Peconic, Little Peconic, Gardiners Bay, etc.


View Larger Map

The expected shells appeared, jingle shells, slipper shells, clams and a sprinkling of oyster drills.  Then I spotted a chalky white cusp of a shell, worn, with a scar.  (Pictured below.  The 3/4" line applies to the image of the interior of the shell and measures the distance from the posterior end to the anterior.)

I had seen this kind of shell before, just never here, and not of this time.  It’s a somewhat common shape among the fossil shells I've collected at the Calvert Cliffs from the Miocene Epoch (23.0 to 5.3 million years ago) – an ark shell – from the Arcidae family of shells.  A recent post features two fossil specimens of Anadara staminea, a much larger, more steeply arched, extinct member of this family.  [Later edit:  I should clarify.  I do know that there are many extant species in this family and many beaches where these shells are common.  On this particular beach, this shell appeared out of place.]

But this is Long Island.  Long Island, in my world, is among the “not-fossil” places, the product of glacier action toward the end of the Pleistocene Epoch (which ran from 2.6 million years ago to 11,700 years ago) that shaped the island and essentially plowed over rock formations that might yield fossils.  But I also would acknowledge that, despite my having dropped it into this category, the island is not totally bereft of fossils, though most of those very, very few that might be found are likely to be invaders from Connecticut, carried over by the glaciers.

I pocketed the shell and, back in the relative warmth of my cottage, consulted two volumes I had at hand:  Harald A. Rehder’s National Audubon Society Field Guide to North American Seashells (1981), and R. Tucker Abbott’s How to Know the American Marine Shells (1961, an aging paperback shedding its pages).

Shell guides are blunt instruments, generally ruling out candidates and only on occasion leaving me with just one species standing.  With these two guides, I rejected a number of ark shell candidates, relying mostly on such obvious physical attributes as the overall shape of the shell, placement and structure of hinge, and features of the umbo.  (The umbo is the beak-like projection that arches over the hinge.  Donald J. Borror, in his Dictionary of Word Roots and Combining Forms (1960), defines the Latin umbo as “a projecting knob; a shield.”  Curiously, the plural is umbones.)

Rehder steered me to the Ponderous Ark (Noetia ponderosa), but I hesitated to come to rest there because of two sources of serious doubt in the description – the size and the range.  My shell was less than an inch long; Rehder said N. ponderosa came in between 1 ½ to 2 ¾ inches.  The distributional range was described as from “Virginia to Florida and Texas.”  To be sure, neither size and range is necessarily dispositive for an identification.  Shell size is tricky given that it is age specific, and ranges defined in 1981 may have shifted in the warm decades since.

But when I read the concluding sentence of Rehder’s description, it was suddenly immaterial whether my shell was a Ponderous Ark or not.  There, in black and white, were words that nudged the continents of my paleontological world in a slightly new direction:

Fossil shells of this species are sometimes found on beaches as far north as southern Massachusetts; washed out from fossil beds, they are testimony that the waters in that area were once warmer.  (p. 672)

Fossils in the wash at the beaches in Massachusetts?  Perhaps even Long Island as well?  Was that possible?  I grabbed Abbott’s book and thumbed to his description of N. ponderosa (a page or two came loose as I did):

Fossil specimens are occasionally found on Nantucket, Massachusetts beaches.  (p. 133)

Not as encouraging, though still acknowledging a fossil connection.

So, what is the possibility of finding fossil shells on Long Island beaches?  I googled “Noetia ponderosa” and “fossil,” and found naturalist Susan J. Hewitt.  She took the lead in reshaping my paleontological reality, writing that the chances of collecting fossil shells on some Long Island beaches are actually quite good.

On some of the exposed sand beaches of the outer Atlantic coasts of New York and New Jersey, the beach drift can contain numerous fossil shells of bivalve and gastropod mollusks. . . . On the beaches that I am familiar with, on days when there is a lot of beach drift, there are usually lots of fossils present.  Sometimes fossil shells are nearly as common as fresh shells, and always they are mixed in with the fresh shells higgledy-piggledy in the drift lines.  (Fossils on the Beach, American Paleontologist, Summer, 2008, p. 12)

Simply amazing.  She plows through the narrow confines of species and locations that Abbott and Rehder had erected for the phenomenon.  In one spellbinding article, Hewitt released me from my paleontological exile on Long Island.  No longer do my summer journeys here have to cut me off from hunting fossils in the surf.

What’s the story behind these fossils?  They date as far back as the late stages of the Pleistocene Epoch, not very old compared to what I’m used to, but still old enough.  Importantly, these are fossil specimens of species that are mostly still with us today, though, such as in the case of the N. ponderosa, not necessarily living in the same geographic range in which they used to live.  More than 12,000 years ago, the Ponderous Ark’s range extended into these waters.

Hewitt cites an article by Thomas C. Gustavson (Paleotemperature Analysis of the Marine Pleistocene of Long Island, New York, and Nantucket Island, Massachusetts, Geological Society of America Bulletin, January, 1976) which shows that these various kinds of fossil shells are Pleistocene in origin, coming from species that lived in this area during a warmer interglacial period.

I haven’t read this piece by Gustavson (unfortunately, my local college connection wasn’t up to penetrating the paywall that the Geological Society of America puts up around its articles).  But, elsewhere, Gustavson has written about fossil finds on the eastern end of Long Island that reveal a fauna characteristic of warmer waters, waters of a temperature closer to those prevailing today from Virginia southward.  (A Warm-Water Pleistocene Fauna From the Gardiners Clay of Eastern Long Island, The Journal of Paleontology, May 1972.  This also hides behind a paywall, but it’s JSTOR and accessible to me.)

Though the specific material he worked with – Gardiners Clay – was found on the South Fork of Long Island, Gustavson mentions other research identifying fossiliferous Pleistocene sediments, including Gardiners Clay and Jacobs Sand, on Robins Island and Gardiners Island.  Both of these small islands are positioned very nicely in the middle of the waters that separate the twin forks of Long Island.  Not too much of a stretch to think that fossil shells on my beaches might have eroded out from those islands.

Hewitt goes on to make my life more complicated by explaining that some extant species that currently live off the Atlantic beaches are likely to be represented in the wash by both fossil and non-fossil shells.  This makes it all the more important to figure out how to tell fossil from non-fossil versions of specimens from the same species.  For instance, it’s a given that fossils will not have the periostracum (an organic layer that covers the shells of many mollusks, it’s the often dark material that seems stuck to the exterior of some shells found on the beach), nor will there be any trace of the actual ligament that once joined two valves together.  Further, bright colors will be gone.  Hewitt observes that “the fossil shells tend to be oddly discolored:  many are various dull and unnatural-looking shades of gray, but they can also be off-white, tan, or faintly rust-colored.”  She emphasizes that a fossil shell will be “opaque and extremely dull-looking, even in the interior of the shell (p. 12).”

These are all attributes I’ve come to expect of the shells I find in places where nearly every shell is a fossil.  When the mixture of shells may contain a healthy offering of non-fossil shells, these indicators will not always do the job of separating out the fossils.  Further, shells that are just somewhat old, on the order of decades or even a century or two, are likely to share many of these fossil-like attributes.  This wont be easy.

Hewitt points to the barrier islands off Atlantic coast beaches of New York and New Jersey, those “ancient, sand bars,” as the source of the fossils.  “Under the topsoil, these [barrier] islands consist of sand deposits of various ages: some old, some very old, and some ancient (p. 13).”  As these barrier islands erode and re-form, they expose “shells from the older, much older, and ancient deposits” and the waves do the rest, unleashing invaders who have lingered from another time and are now shaking things up for me.

Though my collecting is along the beaches between the North and South Forks of Long Island, not on the Atlantic beaches of the South Fork, I think I can still count on ocean currents and wave action to spread fossils my way from those barriers islands.  And, as I noted earlier, the islands between the forks could also offer up their fossils to my beaches.

One final question.  Who is Susan Hewitt?

Well, I really like her vita.  She is a dedicated, published, amateur naturalist who has studied mollusks for many years, recently as a field associate in the American Museum of Natural History’s Division of Invertebrate Zoology, and as a volunteer in the Museum’s Division of Paleontology.  (See the volunteer page for the Division of Paleontology of the American Museum of Natural History.)

This citizen-scientist calls herself “a naturalist in the British tradition.”  All very 19th century.  Appropriately, she seems to be a lingerer from another time.

Postscript

At this stage, I’m not sure of the identity of the shell that helped precipitate this post.  I still think it might be a fossil Ponderous Ark, albeit very much on the small side.  But it may also be a Transverse Ark (Anadara transversa) which has a present-day range covering Long Island and which is typically smaller than the Ponderous Ark.  If a Transverse, this worn veteran of the seas could still be a fossil, or just old.

Of course, there's never a final question.  After consulting several other shell guides for North America's Atlantic coast, all of which suggest fossil N. ponderosa shells may appear on beaches in some places to the north of its current range, I wonder why none of them suggest that fossil shells from other species might be in the drift lines on the beach.

[Later edit:  There's another question that merited consideration in this post.  How does Hewitt distinguish between merely old shells and fossil shells?  It's a matter of how old.  She writes, ". . . these shells are considered fossils only because they are so extremely old . . . . (p. 12)"  It's an accepted distinction.  As paleontologist Donald Prothero notes in Bringing Fossil to Life (1998), the label fossil is applied to "many shells (particularly those of Pleistocene age) [that] still have their original shell material unaltered . . . . (p. 6)"]

Cairns ~ Message Boards to Graffiti

I fear this post mimics a cairn; it came into being through accretion and readers may not be completely sure what they’ve come upon, though clearly communication of some sort is intended.  And somewhere in this is a review of David B. Williams’ new book on cairns.

Clearing out the “things” that accumulate in summer cottages works best if you put sentiment aside, spend as little time as possible considering the item at hand, and ban all second thoughts about the decision to throw something away.  In essence, be ruthless.  The hardest part of this for me involves books, even those that have begun to disintegrate.  This summer, as I worked my way through many boxes of books in my mother-in-law’s cottage, I came across a copy of Armstrong Sperry’s Captain Cook Explores the South Seas, published in 1955 as volume W-19 in the World Landmark book series.  A Landmark book!  Okay, not one of those regular Landmark books, recounting some aspect of America history and sporting those orange colored covers that often stained wet hands.  But a Landmark book nonetheless, possibly among the many that I feasted on as a child.

When the book turned up in a dusty box, I set it aside.  I wanted to celebrate the pleasure I experienced those many years ago with these books, and I also wanted to see how Sperry would describe Cook’s first voyage on the HMS Endeavour to the South Pacific in 1769 to record the transit of Venus.  I touched on this voyage in a previous post about the fascinating Swedish naturalist Daniel Solander.

This book did not draw me in with the same intensity as Landmark books did several decades ago (and the condescending attitude toward the natives of the South Pacific that appeared at times was offputting), but overall it was an enjoyable read, as it should have been given that Sperry was, in his day, a well respected children’s author and illustrator who won the Newbery Medal in 1941 for his novel Call It Courage.  His biography of Cook had those “Landmarkisms” that I remember well, those bubbles of over-enthusiastic writing, those passages of barely plausible dialogue that served to advance the story, and then those moments when the author addressed me directly, to wit

Mark that boy well, Reader!  For young James Cook – tall for his thirteen summers, and with all his belongings swinging in a bundle at the end of a stick – had set forth on a great adventure.  (p. 4)

David B. Williams, in his new book, Cairns:  Messengers in Stone which has just come out, describes Cook as a cairn-builder, erecting them at places he visited during his three voyages of exploration.  As Williams puts it, "The British are well known for exploring the world, but what they really did was travel around and stack stones."  (p. 96)  Sperry mentions only one cairn and it was one that Cook didn’t initiate, but did expand.  This was on his third voyage when he was trying to find the Northwest Passage from the Pacific side.  On Christmas Eve, 1777, according to Sperry, Cook’s two ships came upon a coral atoll with a massive lagoon.  Men went ashore.

A cairn of stones was discovered, to which a bottle had been fastened by a piece of wire.  A strip of parchment within the bottle stated that a French ship had anchored in the harbor four years previously.  On the back of the parchment Cook inscribed a record of his own visit:  “Ships Resolution and Discovery, of his Britannic Majesty.  December 1777.”  He replaced the parchment and sealed the bottle with lead.  Then, building the cairn higher so that it might be seen from the bay, he ordered the Union Jack hoisted.  Thus Christmas Island stepped into history.  (p. 158)

Despite the French vessel having preceded him, Cook seems to be credited with “discovering” Christmas Island in the Line Islands.  (History, of course, is a European invention.)  The island is now called Kiritimati and is part of the Republic of Kiribati.

So, with this cairn, the French intended to communicate to anyone who followed that they had been there.  Cook did what many do to a cairn, he made his mark on it, and in so doing, trumped the French in the name of the King of England.

In his slender, entertaining, and informative book, David Williams has composed a paean to cairns.  I enjoyed it thoroughly.  Still, for me, cairns remain an elusive subject.  As Williams notes, the term itself comes from the Gaelic word for a “heap of stones.”  (I’ll follow his lead and use “stones” and “rocks” interchangeably.)  He writes, “At the most basic level, you can define a cairn as a pile of rocks.”  (p. 115)  That pile may be a few stones or thousands with an aggregate weight of tons.  These are stones as you find them, not altered to fit the stack better.  The pile may not even require a human agent; according to Williams, earthworms or birds may do.

So, is any pile of stones a cairn?  Actually, I’m not sure whether or where Williams would draw the line.  For me, perhaps the distinction between cairn and not-cairn lies in having a purpose (thereby leaving out hoodoos, those towering cairn-like rock structures made by water and wind), or in having certain purposes.  As Williams describes it, though, the purposes for which humans place stones atop one another are myriad.  Previously, in my ignorance, I’d have limited cairns to two categories – navigational aides and memorials for the dead.  Those are certainly among the uses to which they are put, but the broad array of purposes Williams delineates is fascinating.  In his exploration, he takes us on a wide ranging trip around the world, drawing from many native cultures, and he reaches way back in time.  The impulse to build cairns is universal and, on the human scale, seemingly timeless.

Cairns may be message boards; if not containing actual messages like the one Cook found on Christmas Island, then their very existence may be the message – someone came before you, someone is reaching out to you.  Yes, they may mark a trail, placed at the beginning of a particularly difficult spot, or may signal that the path goes in this direction.  But they may also constitute a boundary, a warning to keep out or away, or they may be intended to propitiate local spirits to help you on your journey past this place or the cairn might be a holy place in and of itself.  Your addition of a rock to a cairn may be to signal that you are of the community of those who built the cairn.  The memorializing goes well beyond marking a burial site.  When he describes the massive cairn that built up near where Henry David Thoreau had his cabin at Walden Pond, Williams makes it clear that cairn-building may be no minor act.

Piling up stones to honor a person or event extends back deep into human history.  We find such memorial cairns from Bronze Age Europe, across the Americas, and high on Himalayan peaks.  Most are like Henry’s, built up stone by stone by admirers, family, or friends.

He adds

It’s not just that we recognize the permanence of stone, but also that we realize the oneness of our planet, how we are all part of the same big rock, and that when we place a stone on a ceremonial cairn we are establishing an intrinsic connection with that person and that place.  Or as Thoreau put it, “The whole earth is but a hero’s cairn.”  (p. 126)

Then there are the artists, about whom Williams writes, who stack stones.  Yes, these rock sculptures reflect that apparently basic human impulse to put one rock onto another.  But my sense of what constitutes a cairn became very tenuous at that point in his book – are these stacks really cairns?  I’m not quite sure how to explain why I balk at deeming artists’ stone stacking to be cairn building, but accept without question that the mound of blocks of ice (not rocks) erected by Robert F. Scott and his men in 1912 to mark their presence at the South Pole is a cairn.  I don’t believe it’s just that Scott called it a cairn in his journal, I think it’s more about the purpose of the enterprise.  For Scott and his men this was how they could mark and tell of the attainment of their goal (a profoundly sad event because they’d lost the race, and would ultimately lose their lives).  Further, had there been stone to use, I’m sure they would have.  Ice was what they had.

True to the geological expertise reflected in his previous book, Stories in Stone:  Travels Through Urban Geology (2009, which I reviewed here), Williams well describes the geological aspects of the cairn.  Sedimentary rocks are most likely to be used in erecting a cairn simply because that’s what’s typically around on the surface of this planet of ours.  And that’s a good thing for cairn building because this kind of rock often breaks apart in ways that offer two relatively flat sides.  Building cairns on paths traversing U.S. mountains is likely to involve the use of igneous rocks because that’s what the mountains are made of.  Williams asserts, and I think he’s right, that

We intuitively sense that a cairn represents a cross between the realm of geology and the realm of humans.  Both realms are rich, and when they intersect – whether in the form of an earthquake, a volcano, or a cairn – it merits our attention, draws us in, and gives us a richer connection to the world around us.  (p. 37)

Cairns may harmonize with nature or they may intrude.  But, as Williams makes clear, cairns alter the landscape.  In fact, I found the book to have a subtext that posits that this altering is often for the worst.  For some who go out into nature, the discovery of a cairn in the course of a long hike is analogous to finding graffiti, a “Kilroy was here” reminder.  But, more than that, William warns that the very act of creating the cairn may disturb fragile ecosystems, even as it creates an ecology all of its own.

Walt Whitman penned some wonderfully dramatic lines about cairns in Leaves of Grass.  They appear in the portion titled Salut Au Monde! which exuberantly explores the sounds and sights of the world.

          I see the places of the sagas,
          I see pine-trees and fir-trees torn by northern blasts,
          I see granite bowlders and cliffs, I see green meadows and
          lakes,
          I see the burial-cairns of Scandinavian warriors,
          I see them raised high with stones by the marge of restless
          oceans, that the dead men’s spirits when they wearied
          of their quiet graves might rise up through the
          mounds and gaze on the tossing billows, and be
          refresh’d by storms, immensity, liberty, action.

Ah, cairns and other living things.