An earlier article here covered 3-D printers, which use modified inkjet technology to create solid objects with extremely complex shapes. The printers use a variety of techniques to solidify arbitrary areas on the surface of a powdered substrate, which supports the object as it is built up layer by layer. Designers commonly use 3-D printers for prototyping things like consumer electronic products, ensuring that they will be manufacturable before expensive metal molds are created to enable mass production. I ran into an old acquaintance the day that article ran who had never heard of Interesting Thing of the Day, so I told him about the site. He asked me what that day’s topic was, and I happily described the 3-D printers. He said, “Oh yeah, I know about those. Did you know they’re also using them to ‘print’ human tissue?” Um…no, I had no idea. It turns out that the humble inkjet printer has quite a few tricks up its sleeve—including, incredibly, the capability of manufacturing living skin and other organs.

Cell Mates
Growing individual human cells is not especially difficult. Take a sample of healthy cells, provide them with the right nutrients and environment, and they will grow and multiply. When multiple tissue cells are placed in close proximity to each other, they have a tendency to fuse together. Because of this phenomenon, hospitals can “grow” new skin to be used as grafts for burn patients using the patient’s own skin cells. However, this technique does have significant limitations. In particular, the skin cannot be made very thick because there’s no way to get blood to deeper cells—the process grows a homogeneous sheet of skin without the essential network of blood vessels, not to mention pores and other minute structures.

But creating intricate solid structures layer by layer is easy for a 3-D printer. So researchers have adapted old inkjet printers to hold a suspension of human cells in one reservoir and a gel-like substrate in another. Each pass of the print head lays down a pattern of cells held in place by the gel; when the next layer is applied, the adjacent cells begin to fuse to the layer beneath. If, for example, each layer contains a circle of cells in the same location, the result will be a tube—in other words, a structure very much like a blood vessel. A printer could in fact hold different kinds of cells in an array of ink reservoirs (like those used by color printers), theoretically enabling the creation of entire organs.

It’s All Beginning to Gel
The gel that functions as the substrate for this type of tissue printing is itself quite interesting. As with the powdered material used in rapid prototyping, the gel must be removed after the rest of the structure has solidified. Called thermo-reversible gel, it has the unusual property of being solid above 32°C and turning into a liquid when cooled below 20°C. So after the cells have fused, the tissue is cooled and the liquefied gel simply drains away.

Although the most obvious application for such a technology is producing skin grafts that are more robust than what’s currently possible, one day much thicker organs could be printed—making the inkjet printer a veritable tool for manufacturing replacement human parts. But although early laboratory experiments have yielded impressive results, researchers caution that the technology is in its infancy—likely a decade or more away from even initial trials with real patients. One of the hurdles to be overcome is that cells take time to fuse together into tissue, but can only survive for a short period of time without nutrients and oxygen. So the thicker a printed organ is, the more difficult it will be to keep it alive and healthy until the gel can be removed and it can begin getting nourishment from blood (or a reasonable facsimile thereof). Furthermore, remember that the printers don’t actually create the cells; they only arrange them. All the cells must have been grown in advance, a process that can take weeks (and that cannot be done equally well with all types of cells). So don’t expect to show up at the emergency room and get a new pancreas printed while you wait. —Joe Kissell

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When I was studying linguistics in graduate school, the question people asked me most often was, “So how many languages can you speak?” I’d roll my eyes and say, “One, almost.” I’d then try to explain that I usually get by pretty well in English, that I can order food in a French restaurant without embarrassing myself, and that I’ve picked up a smattering of phrases in half a dozen other languages—but that’s pretty much it (unless you want to count computer languages or ancient Greek and Hebrew, of which I know just enough to mistranslate an inscription here and there). Linguists, I would say, are not necessarily polyglots; the study of linguistics is not about learning a bunch of languages but rather about understanding the nature of language generally: how the brain creates and interprets it, how children learn it, how it functions in society, how to model it computationally, that sort of thing. (At this point listeners would generally nod, try valiantly to suppress a yawn, and change the subject.)

In the course of my studies, I came across a fringe linguistic theory that is, even by the most generous standards, far from being generally accepted, or even respected. The theory is known as tagmemics; its inventor and primary proponent, the late Dr. Kenneth L. Pike, was on my thesis committee. So I got to spend some quality time getting to know the man and his theory—which, though I argued forcefully against its shortcomings, is nevertheless quite interesting. It’s the one linguistic theory that ordinary, nonacademic human beings have a reasonable chance of comprehending without months of study.

Understanding How Language Works
What’s a linguistic theory, anyway, and why do we need one? Linguists studying the way language works can observe what people say or write, but they can’t tell what’s going on in someone’s mind. To oversimplify greatly, that’s what a linguistic theory tries to figure out—the mental processing behind language. The reason for doing this varies from one linguist to the next: some are searching for the origins of a particular language or evidence that language is basically hard-wired in the brain; others want to find easier ways to learn or teach languages, or improve computer speech recognition. But whatever the motivation, a linguistic theory—a model that describes how language is put together and predicts how new words and sentences will be formed—is an essential starting point.

In the 1930s, Pike began studying phonology—the rules that govern how sounds are combined into words. Some sounds are regarded as the same by native speakers of a given language, even though they are objectively, or phonetically, different. Linguists use the term phoneme to describe a sound that speakers intuitively regard as being unique and meaningful in a language: thus two sounds may be phonetically different but phonemically the same. For example, in English there’s a sound we call “schwa”—a sort of neutral vowel sound that substitutes for other vowel sounds when it’s in an unstressed syllable. We don’t need to use the schwa symbol when spelling words that include it; we know intuitively and automatically when another sound—like “a,” “e,” or “u”—should be shortened into a schwa. So because it is simply a variant that occurs in very well-defined situations, schwa would not be a phoneme in English. On the other hand, there’s no rule that could predict when “k” would be used versus “d,” so both the “k” sound and the “d” sound must be phonemes in English. Finding the phonemes—the meaningful units of sounds in a language—is a basic part of the analysis of any language.

Etic and Emic
What Pike wondered was whether there might be something analogous to the phoneme in grammar—that is, at the level of words. To take a fairly trivial example, consider a pair of synonyms, such as “aid” and “assist.” Pike would say that even though these two terms are objectively different, the fact that they can be used and understood in the same way in a given context makes them equivalent at the level of grammar. He used the terms “etic” (as in phonetic) and “emic” (as in phonemic) to describe objective and subjective units of meaning, respectively. Thus, in this example, “aid” and “assist” are etically different but emically the same. Pike originally called the minimal grammatical unit of (emic) meaning a grameme but later changed the term to tagmeme, which he felt was more generic.

A tagmeme is basically a composite of form and meaning, a “unit-in-context.” Where many other linguists only wanted to study the objective form of language (that is, its “etic” aspect), Pike felt that the interesting thing was how language actually functions for users in real life—its “emic” aspect. So the tagmeme, as Pike’s fundamental unit of language, is described in terms of four features (or “cells”)—slot (where the unit can appear), class (what type of unit it is), role (how the unit functions), and cohesion (how the unit relates to other units). Pike found that the very same structures that appeared on lower levels also appeared on higher levels—as sounds formed words, words formed sentences, and sentences formed discourse, Pike used tagmemes to describe these larger and larger units. And he begin to think: if the etic/emic distinction applies to all levels of language, perhaps it was an even more basic, more general principle that could explain a great many other things too.

Beyond Grammar
In his monumental (and very, very heavy) book Language in Relation to a Unified Theory of the Structure of Human Behavior, Pike claimed that the same kinds of structures, rules, and procedures found in phonology apply not only to grammar and discourse, but in fact to all of human behavior. He analyzed events such as football games and church services using his tagmemic system, with the rather lofty goal of proving that all human behavior is basically linguistic.

Of course, the fact that a football game and a sentence can be described using the same methodology and structures, while very interesting, doesn’t really prove that a football game is linguistic. And most linguists seemed to feel that as a descriptive model, tagmemics was not as rigorous or objective as other models, so it didn’t lend itself well to serious scientific inquiry. But from Pike’s point of view, looking at language as an objective formal system was missing the point; behavior that is fundamentally subjective can only be understood and described meaningfully if the observer allows context to play a role at every level.

The Wide World of Tagmemics
Another of Pike’s main claims was that language is deeply hierarchical, in several simultaneous ways. Sounds and intonation form a phonological hierarchy; words and sentences form a grammatical hierarchy; and meanings—whatever a speaker is talking about—form a referential hierarchy. All three hierarchies interlock and operate at the same time, and of course, what could be said of the hierarchy of language could also be said of the hierarchy of all behavior. As the theory developed over the course of several decades, Pike expanded it even further to include insights from other fields. From quantum physics, for example, Pike borrowed the notion that any event can be seen from the perspective of particle (a static view of a unit), wave (a dynamic view), or field (a unit in relation to other units).

Pike applied tagmemics to rhetoric, poetry, science fiction, and philosophy, among other fields. Others have taken it further—I’ve even seen a document using tagmemics as a model for learning the programming language Perl. While it never did (and never will) meet the day-to-day needs of most linguists, tagmemics has managed to maintain a small but loyal following among researchers in a wide variety of disciplines. The key insights of tagmemics—that context is essential, behavior involves overlapping hierarchies, and viewpoint affects one’s analysis of data—turn out to be surprisingly effective for understanding many kinds of phenomena. This obscure linguistic theory is in fact a pretty good way of thinking about what it means to be human. —Joe Kissell

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More Information about Tagmemics…

For a good basic introduction to tagmemics, have a look at either Linguistic Concepts: An Introduction to Tagmemics (1982) or Text and Tagmeme (1983; coauthored by Pike’s wife Evelyn). Both books are out of print but can frequently be found used.

A Web site that attempts to describe tagmemics as applied to discourse is here, but it reads sort of like lecture notes—i.e., something you’d probably understand better if someone were explaining it in person. Programmer Allison Randal created this PDF File to go along with her lecture on the application of tagmemics to Perl at a software conference. If you’re really interested, you can watch a video of the lecture.

Ken Pike died in 2000; the Summer Institute of Linguistics has a Web site dedicated to his life and work.

My master’s thesis in linguistics (University of Texas at Arlington, 1991) dealt with the contextual aspects of meaning but suggested that tagmemics would be much more useful if it substituted a phenomenological analysis for simple subjectivity. With a nod to Pike, I titled it Meaning in Relation to the Phenomenological Observer. It is not available in digital format, I’m afraid, but if you’re a glutton for punishment you can order a hard copy from UMI Dissertation Express for US$34 plus tax. (Enter “1344945” as the order number to locate it quickly.)

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People who want to make fun of the Canadian dialect of English invariably start with one of its two most idiosyncratic features. The pronunciation of the diphthong “ou,” of course, is one of them—in words like out and about, Americans exaggerate both the gliding and rounding of the vowels so that it sounds like the “ow” in power, whereas the stereotypical Canadian pronunciation is closer to oat and a boat. I know lots of Canadians who protest this characterization, pointing out that Americans butcher the language much more egregiously. They may say, “Every dialect of English has its faults, eh?” This is the second oft-ridiculed peculiarity of Canadian English: turning a statement into a question by adding the word “eh” at the end, which means, approximately, “Isn’t that so?”

Needless to say, not all Canadians fit the stereotype—my wife, for example, rarely uses “eh,” just as I avoid most of the influences of Pittsburghese. Some of her family members from Saskatchewan, on the other hand, say “hey” instead of “eh,” and there are many other regional variations of English within Canada, just as there are within other English-speaking countries. But whether or not one uses “eh” (or “hey”), every English speaker knows dozens of ways to add a word or a phrase to the end of a statement so that it becomes a yes/no question. Questions formed in this way are called tag questions.

You’re It (Aren’t You?)
In one of my first graduate linguistics courses in grammar, we studied English tag questions at great length, because they nicely illustrate a simple, rule-based grammatical transformation. The simplest way to make a tag question in English is to repeat the verb, negate it, and then repeat the subject. For example, “He is smart” becomes “He is smart, isn’t he?” If the verb is already negative, you just make it positive. “It won’t rain” becomes “It won’t rain, will it?” In most cases, if a sentence doesn’t use a “be” verb, tag questions are created using a form of the verb “do”: “This scarf matches my hat, doesn’t it?” Depending on the verb and the context, there are numerous other variations, along with special exceptions to the rules. Every student in elementary school is taught that when speaking of yourself, you must use the awkward-sounding “Aren’t I?” to form a tag question unless you’re willing to phrase it as “Am I not?”

Beyond these basic kinds of tag questions, though, there are many other ways of achieving the same (or very similar) result. “Don’t you think?” is very common, as are “Right?” and “OK?” and sometimes even “Huh?” In certain parts of the U.S., Canada, and England, “Isn’t it?” is shortened to “innit?” and used as an all-purpose tag question, even where the verb doesn’t seem to match, as in “This shirt costs a lot of money, innit?” But if you think of “innit?” as short for “isn’t it so?” you have a nice parallel to the all-purpose French tag question, which also shows up in English. “This foie gras is splendid, n’est-ce pas?” And oddly enough, “yes” and “no” can often be used interchangeably to form tag questions. “We’re having fun, yes?” means about the same as “We’re having fun, no?”

Tag Questions Have Many Uses (Don’t They?)
What I have always found most interesting about tag questions is their many and varied uses. Ostensibly they are questions that seek agreement or disagreement with whatever the original statement was, but more often than not, they are used for reasons other than gathering information. In some regional dialects of English, tag questions occur quite frequently—every few sentences or so—with the net effect of softening the overall impact of the speaker’s statements. In other words, tag questions can make speech sound more polite or deferential by implicitly suggesting, “I could be wrong about this; what do you think?” This is also one of the functions of the Canadian “eh”—just as a Canadian will often say “Sorry!” if you step on his toes, frequent use of “eh” can serve the social purpose of limiting one’s impression of self-importance.

Very often, tag questions are used mainly as a tool to move conversations along, to involve other participants. A tag question can invite feedback—anything from a nod to a “Yeah, sure,” to a lengthy response. But with very few exceptions, tag questions that expect a response are looking for a positive response: an agreement with the speaker’s original statement before it became a question. They say: “I believe such-and-such. Do you agree?” So tag questions can exert a subtle (or sometimes not-so-subtle) pressure on the listener to respond positively, like a preacher who makes a string of bold statements followed by “Amen?” It would be unexpected, to say the least, for a member of the congregation to shout out “Not really!” So just as tag questions can be used as a means of expressing courtesy, they can also be misused as a way of controlling a conversation, inducing guilt, or expressing passive aggression. Hence the infamous “You’d never leave me, would you?” It’s not easy for someone to respond, “Oh, sure I would!”

Tag questions can be used to make accusations, especially when followed by an explicit demand for agreement: “And then you bludgeoned the victim with Volume XI of the Oxford English Dictionary, didn’t you? Admit it!” They’re also a perennial favorite among parents: “You didn’t finish your vegetables, did you?” or “You need a nap, don’t you?” In fact, tag questions are a veritable Swiss army knife of English constructions, with almost as many possible uses as expletives. Although tag question formation is usually taught to people learning English as a second language, the full range of uses and variations is rarely addressed, making them confusing for people who don’t grasp their underlying motivations.

You Don’t Get It, Eh?
Even English speakers don’t always understand the unwritten rules for tag questions. Several times I’ve heard Americans try unsuccessfully to imitate a Canadian by saying something like, “Isn’t it cold up here, eh?” And that’s simply wrong; a tag question only works if it modifies a statement (or, in some cases, a command: “Stay for dinner, eh?”).

Tag questions are fascinating, aren’t they? You enjoyed reading about them, didn’t you? You will keep reading Interesting Thing of the Day every day, won’t you? —Joe Kissell

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More Information about Tag Questions…

People learning English as a second language can try this tutorial (with quiz) or this online quiz to test tag question formation.

For a sample of how linguists look at tag questions, see Perceptions of Assertiveness as a Function of Tag Questions by Rebecca R. Culberson.

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The first couple of times I visited Saskatchewan, where my wife’s family lives, it was winter. Temperatures hovered around –40°, making holiday shopping along the streets of downtown Saskatoon a challenge. Even bundled to the gills, we could barely stand to be outside for more than a few minutes. Morgen assured me that during the summer (or “mosquito season,” as it is affectionately known), the prairies of southern Saskatchewan took on an entirely different look and were quite hospitable to humans. But I was thinking, this is why they invented malls. Malls are good. Let’s go to the mall! We went to the mall.

Moosey in the Sky with Diamonds
I like to kid my wife about Saskatchewan: the monotonous flatness of the landscape, the dearth of trees, the nasty winter weather, the fact that the province’s slogan, “Land of Living Skies,” suggests there’s not much interesting about the land itself. Morgen, in turn, can kid me about western Pennsylvania (where I grew up), which has its own peculiarities. But even though Pennsylvania has no shortage of oddly named towns, Saskatchewan’s legendary town of Moose Jaw takes the cake. Although everyone in Canada has heard of Moose Jaw, it’s known more for its silly name than for any other characteristic. Which is a shame, because if you dig a little bit, you can find all sorts of interesting things in Moose Jaw.

Moose Jaw, located just west of the provincial capital of Regina in south-central Saskatchewan, most likely got its name from a Cree word meaning “warm breezes” via folk etymology—though there are several other theories too, including one that the river running through town was thought to be shaped like a moose’s jawbone. Warm breezes or not, Moose Jaw (like the rest of Saskatchewan) gets plenty cold in the winter. In the early 1900s, when the town was beginning to undergo significant growth, most of the larger buildings were heated by steam, with coal-powered boilers located in the basements. The engineers who kept the heating equipment running didn’t like having to go upstairs and outside in the cold repeatedly to move from building to building, so they arranged for the creation of a series of tunnels linking the basements to provide easier access. Over a number of years, the tunnels expanded and interconnected, becoming a large network.

Down and Out in Moose Jaw
Not long after the tunnels were built, a wave of Chinese immigrants arrived in Moose Jaw. Anti-Chinese sentiment at the time made it difficult for these immigrants to live and work in public view, yet business owners valued them as a source of cheap labor. So the tunnels were expanded and used as both living quarters and workplaces. Conditions were harsh in the tunnels and pay was poor, but the workers stayed because their options for earning money in the outside world were limited.

During Prohibition (1917–1924 in Saskatchewan and 1920–1933 in the U.S.), Moose Jaw became a hub for liquor distribution both domestically and across the border. Along with speakeasies, gambling and prostitution became big businesses in the town. The tunnels provided a conveniently obscure place for all these activities. According to several reports—though no conclusive evidence exists—Al Capone himself called Moose Jaw home for a short while, overseeing a profitable bootlegging operation in person. Because of the town’s connection to organized crime in the U.S.—and its physical link to Chicago via the Canadian Pacific Railway’s Soo Line, used heavily for transporting illicit alcohol—Moose Jaw became known as “Little Chicago.”

Over time, most of the tunnels fell into disuse; many were filled in or blocked off as new buildings were constructed. But a portion of the tunnel network that remains has been developed into an elaborate, theatrical tourist attraction. Guests can take either or both of two tours featuring both live actors and animatronic figures. One tour highlights the tunnels’ use by Chinese immigrants; the other tour focuses on the organized-crime angle. The tours attract more than 100,000 visitors per year—about three times the town’s population. The tunnels are now a source of civic pride, though they may never match the incredible drawing power of the town’s unusual name. —Joe Kissell

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More Information about The Tunnels of Moose Jaw…

Visit the official Tunnels of Moose Jaw site for more information about the tours.

Other Moose Jaw tunnel resources include:

cover art

Mary Harelkin Bishop has written a series of children’s books that take place in Moose Jaw: Tunnels of Time, Tunnels of Terror, and Tunnels of Treachery.

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Several years ago, the company I worked for had a big Halloween celebration. One of my coworkers decided that a group of us needed to dress up as the Three Little Pigs and the Big Bad Wolf. So she worked for days sewing costumes for all of us, and even brought in plastic pig noses for us to wear. For an authentic touch, she asked that we also decorate our desks with the building materials featured in the story. I got the short straw (so to speak) and ended up making a pathetic mess by scattering straw all around my desk, and the “pig” who used sticks didn’t fare much better. But our colleague with the brick “house” simply printed out a huge brick pattern on a large-format color printer and wrapped it around his desk. In life as in the story, his design was clearly the best.

It is difficult to set aside the bias that straw is an inappropriate building material, even knowing that wolves lack the lung capacity to blow down a straw house. And yet people have been building sturdy, comfortable houses out of straw bales for more than a century. This building technique has been, shall we say, a bit slow to catch on—and is not without its limitations. But using straw as a building material turns out to have some interesting merits.

If You Can’t Eat ‘Em…
Straw is what’s left over when grains like wheat, barley, or rice are harvested—basically the hollow stalks. Unlike hay, which can be used to feed animals, straw is a nearly useless agricultural byproduct. Millions of tons of straw must be burned or otherwise disposed of each year. Inconveniently, it doesn’t even decompose rapidly. Automated baling machines, invented in the 1890s, compact straw into tightly compressed blocks, so that they will at least occupy as little space as possible. Faced with a surplus of straw bales, a lack of trees, and a cold winter approaching, some settler long ago decided to stack up the bales and use them as the walls of a house. This worked surprisingly well, and after years of refinement, straw bale construction is beginning to gain respect as a mainstream technique.

Walls made of straw bales are held together and reinforced with rebar (or sometimes, wooden or bamboo stakes). In some designs, walls made entirely of straw bales support a roof; in others, a conventional wooden frame is used as the load-bearing structure while the straw bales form the exterior shell. Straw will rot if exposed to moisture, so to keep it dry, both interior and exterior surfaces are sealed with plaster, stucco, or adobe. The net effect is that walls of a finished straw bale building look just like any other wall, only a bit thicker.

The Last Straw
One of the strongest arguments for using straw as a building material is that it saves lumber. Even if wood is readily available, straw is invariably much cheaper. It’s a rapidly renewable resource, and one that usually goes to waste. A wall made of straw bales also has dramatically higher insulating properties than a standard wooden wall, making buildings that use them very energy-efficient. Straw bale houses are also easier to build than wooden frames, even by people with little experience.

Studies performed by various universities and government organizations have shown that a properly constructed straw bale house, sealed well with plaster, is actually less susceptible to damage by fire than a wooden building. Although you wouldn’t build a high-rise condo out of straw bales, a carefully designed one-story building is also quite safe in an earthquake. Owners must be careful to keep all cracks sealed, though, because once infiltrated by moisture, bugs, or rodents, a straw bale wall will rapidly lose its integrity. Last but not least, straw bale buildings are extremely resistant to damage by wind. So much for the Big Bad Wolf. —Joe Kissell

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More Information about Straw Bale Houses…

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For a good book on straw bale buildings, see The Straw Bale House by Athena Swentzell Steen, Bill Steen, David Bainbridge, and David Eisenberg.

Other straw bale resources:

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