When Do Fish Sleep? Part 18

Since his main concern was to go to sleep in dad's car, he didn't retrieve his shoe-he just closed the door and got comfortable. Dad and his other son had been in the car waiting; the three took off as soon as my one-shoed friend closed the door. The shoe was still on the roof of the car, and apparently survived the 25- and 35-mph speed limits of the neighborhood in which they lived. Once on the highway, the shoe was doomed. Indeed, once the three arrived at work, they called Mom, who sought out the missing shoe, locating it on the side of the highway.

I doubt that this is the definitive answer that you're looking for, but it does explain how at least one shoe got on the road by itself.

The Margaret Mead Field Research Award. Goes to Laurie McDonald of Houston, Texas. Laurie once lived in Providence, Rhode Island, and found scores of single shoes alongside the highway between Warwick and Pawtucket while driving to and from work. Laurie collected seventy shoes in a period of six months.

Among her discoveries were mostly tennis shoes, most left-footed; "very early on Sunday mornings, I would inevitably find a few brand-new patent leather platform shoes sitting upright on the side of the road, waiting to be plucked."

In 1979, Laurie was inspired to write a series of short stories, consisting of hypothetical explanations of how single shoes landed off the highway. In one, the protagonist was a hippie, sticking out his hand to hail a car. Instead, the outstretched hand became a shooting target for unneeded boots of army servicemen.

Although Laurie offers no theoretical breakthroughs, we nevertheless owe her a great deal for proving conclusively that single shoes are deposited on the highway at an alarming rate, at least in Rhode Island.

Confessions The "10-4, Good Buddy" Award. Goes to Robin Barlett of Erie, Pennsylvania. Robin writes: My husband is a truck driver and I went with him on a run. He got tired and pulled off to the side of the road to sleep, and I went back into the bunk and took my shoes off.

We got up late at night and my husband had to go to the bathroom. n.o.body was on the highway so he just hopped out to go and he must have kicked my shoe out, for it was not there when I tried to find it.

The Foot Out the Window Routine Award. Goes to Brian Razen Cain of Chipley, Florida, the last honest man in the world. Many readers theorized that single shoes are remnants of pa.s.sengers who nap with one (or both) shoes dangling out car windows. But Brian was the only one to admit it. Brian fell asleep on the Florida Turnpike and woke up to find himself semishoeless. His response? The normal one: "I simply threw the other one out the window too."

The Dog Ate My Homework Award. Goes to Jay Lewis of Montgomery, Alabama.

The shoes were dropped there by animals. Various beasties are attracted by the taste and smell of salt-impregnated leather. Since animals have trouble getting more than one shoe in their mouths, they only carry one of the pair away. Where they finally discard it is where you see it-invariably without its mate.

C. Lynn Graham of Pelham, Alabama, adds that dogs tend to think that they will carry a shoe in their mouths forever. But as soon as they are distracted by a car coming down the road, the shoe pales compared to the chance to chase a pa.s.sing car.

Surprisingly only one soul, Jennifer Ballmann of Jemez Springs, New Mexico, was willing to admit that she was the personal victim of doggy single-shoe syndrome. Two questions arise: Can a Saint Bernard carry two shoes at a time? Can a Pekingese carry one shoe at a time?

I Did it for the Sake of Science Award. Goes to an anonymous caller on a Detroit, Michigan, radio show hosted by David Newman. This caller, a paramedic, confessed that he was personally responsible for dropping several single shoes in the past week.

When administering CPR paramedics are trained to take off the victim's shoes, in order to promote better circulation. Many times in transporting a heart attack victim from a residence the shoes are taken off hastily and get lost before the patient enters the ambulance.

Will insurance companies pay for the missing shoes of patients not responsible for their loss?

The Motorcycles are Dangerous Even WITH a Helmet Award. Goes to Tom Vencuss of Newburgh, New York. Several readers speculated that single shoes were discarded wedding shoes. "Well," claims Tom, "not quite..."

I was scheduled to be the best man at my cousin's wedding in Schenectady, New York, a two-hour ride from my home in Poughkeepsie. Prior to the wedding, I needed to make a quick run up to get fitted for my tuxedo. It was a beautiful afternoon so I decided to ride my motorcycle. I dressed in my normal riding gear but took a pair of dress shoes to wear at the fitting. I decided not to take a bag along since I would not be spending the night. So I strapped the shoes to the back of the bike.

Several hours later, as I pulled into the parking lot for the tuxedo rental, I reached back to find only one shoe. The other, no doubt, was sitting lonely on a stretch of the New York State Thruway. Though it was an expensive afternoon, it did solve one of life's little mysteries.

Do we have the definitive, smoking-gun solution to this Frustable? We're afraid not. But after all, philosophers have been arguing over less important topics for thousands of years. Together we have raised the level of discourse on this topic to stratospheric heights. Maybe our grandchildren will find the ultimate answer.

Submitted by Julie Mercer of Baltimore, Maryland. Thanks also to Bess M. Bloom of Issaquah, Washington; and Sue S. Child of Red Bluff, Louisiana.

A free book goes to Laurie McDonald of Houston, Texas, to inspire her to conduct further hard research on this important topic. Thanks also to Elaine Viets of the St. Louis Post-Dispatch, for her generosity.

FRUSTABLE 2: Why Are b.u.t.tons on Men's Shirts and Jackets Arranged Differently From Those on Women's Shirts?

Of all the Frustables, none yielded less new ground than this one. Although more readers tried to answer this Frustable than any other but number three, few added much beyond the speculations we offered in Why Do Clocks Run Clockwise?

This much we know for sure: b.u.t.tons were popularized in the thirteenth century, probably in France. Before that, robes tended to be loose and unfitted and were fastened by strings, hooks, or pins.

Many readers said that men in the thirteenth century wore swords on the left hip under their coats. When they cross-drew their sword, they risked catching their sword if their garments were arranged right over left. By changing the configuration so that left closed over right, they could unfasten jacket b.u.t.tons with their left hand and draw their sword with their right hand more quickly and safely.

An equal number of readers insisted that the different b.u.t.ton configurations come from the custom of rich women having handmaidens who dressed them. Because clothes, as everything else, were designed for right-handers, the women's arrangement made it easier for maids to b.u.t.ton their mistresses' blouses and dresses. Male aristocrats presumably dressed themselves.

The third popular answer is that women's b.u.t.ton arrangement is most convenient for breast-feeding, so that the mother can unb.u.t.ton her blouse with her right hand and rest the baby on her left arm.

None of the three popular explanations is convincing to us. All of the clothing historians we spoke to did not accept these pat answers either. Only the second theory explains why men's and women's b.u.t.tons need to be different, and there is one inherent problem with this theory-many rich men were indeed dressed by servants. We don't put much stock in the breast-feeding theory either. One book we found mentioned that the women's arrangement made it easier for women who were breast-feeding while holding their babies in their right arms.

Much of the written material we have read on this subject mentions all three of these nonrelated theories, an indication to us that these explanations are based more on supposition after the fact than solid evidence. Robert Kaufman, reference librarian in the Costume Division at the Metropolitan Museum of Art in New York, told Imponderables that this Frustable has been among his most often asked questions. He and others have done considerable research on the subject and found no credible evidence to sustain any particular argument.

A few readers offered some imaginative answers to this Frustable. A surprising number mentioned an intriguing variation of the handmaiden theory: By switching the b.u.t.ton arrangement for the two s.e.xes, it's easier for the two s.e.xes to unb.u.t.ton each other's clothing during a s.e.xual encounter. Hmmmmmm.

Along the same garden path comes our favorite contribution to this discussion, from Erik Johnson of Houston, Texas: "The b.u.t.ton arrangement is so that when a couple is driving in a car, with the man driving, they can peek inside each other's shirts."

Submitted by Julia Zumba, of Ocala, Florida. Thanks also to Kathi Sawyer-Young of Encino, California; Mathew Gradet of Ocean City, Maryland; Jodi Harrison of Helena, Montana; Sheryl K. Prien of Sacramento, California; Harry Geller of Rockaway Beach, New York; Terry L. Stibal of Belleville, Illinois; Mary Jo Hildyard of West Bend, Wisconsin; Tom and Marcia Bova of Rochester, New York; Robert Hittel of Fort Lauderdale, Florida; and many others.

FRUSTABLE 3: Why Do the English Drive on the Left and Just About Everybody Else on the Right?

Quite a few readers, justifiably, took us to task for the phrasing of this Frustable. By saying "just about everybody else" drives on the right, we didn't mean to slight the rest of the United Kingdom, Ireland, India, Indonesia, Australia, South Africa, Kenya, Thailand, j.a.pan, and many other nations, all of which still drive on the left side of the road. But because most of these other countries adopted their traditions while a part of the British Empire, we wanted to give the "credit" where it was due.

So how did this left-right division start? All historical evidence indicates that in ancient times, when roads were usually narrow and unpaved, a traveler would move to the left when encountering another person on foot or horse coming toward them. This allowed both parties to draw their sword with their right hand, if necessary. If the approaching person were friendly, one could give the other a high five instead. Military policy, as far back as the ancient Greeks, dictated staying to the left if traveling without a shield, so that a combatant could use his left hand to hold the reins and need not brandish the sword or lance crosswise, risking the neck of the horse.

Richard H. Hopper, a retired geologist for Caltex, has written a wonderful article, "Why Driving Rules Differ," the contents of which he was kind enough to share with Imponderables readers. Hopper believes that the custom of mounting horses on the left-hand side also contributed to traffic bearing left. In many countries, pedestals were placed alongside the curbs of the road to help riders mount and dismount from their horses. These approximately three-feet-high pedestals were found only on the left side of the road. Long before the pedestals were erected, hors.e.m.e.n mounted and dismounted on the left, probably because their scabbards, slung on the left, interfered with mounting the horse; the unenc.u.mbered right leg could be more easily lifted over the horse.

Until 1300 A.D., no nation had mandated traffic flow. But Pope Boniface VIII, who declared "all roads lead to Rome," insisted that all pilgrims to Rome must stick on the left side of the road. According to Hopper, "This edict had something of the force of law in much of western Europe for over 500 years."

The movers and shakers of the French Revolution weren't excited about having a pope dictate their traffic regulations. Robespierre and other Jacobins encouraged France to switch to right-hand driving. Napoleon inst.i.tutionalized the switch, not only in France but in all countries conquered by France.

Why did the United States, with an English heritage, adopt the French style? The answer, according to Hopper and many others, is that the design of late-eighteenth-century freight wagons encouraged right-hand driving. Most American freight wagons were drawn by six or eight horses. .h.i.tched in pairs; the most famous of these were the Conestoga wagons that hauled wheat from the Conestoga Valley of Pennsylvania to nearby cities. These wagons had no driver's seat. The driver sat on the left-rear horse, holding a whip in his right hand. When pa.s.sing another vehicle on a narrow ride, the driver naturally went to the right, to make sure that he could see that the left axle hub and wheel of his wagon were not going to touch those of the approaching vehicle.

In 1792, Pennsylvania pa.s.sed the first law in the United States requiring driving on the right-hand side, although this ordinance referred only to the turnpike between Lancaster and Philadelphia. Within twenty years, many more states pa.s.sed similar measures. Logically, early American carmakers put steering wheels on the left, so that drivers on two-lane roads could evade wavering oncoming traffic. Although Canada originally began driving on the left-hand side, the manufacture of automobiles by their neighbors to the south inevitably led to their switch to the right. Although Ontario adopted right-hand driving in 1812, many other provinces didn't relent until the 1920s.

Great Britain, of course, stayed with the ancient tradition of left-side driving and not just out of spite. Their freight wagons were smaller than Conestoga wagons and contained a driver's seat. Hopper explains why the driver sat on the right-hand side of the wagon: The driver sat on the right side of the seat so that he could wield his long whip in his right hand without interference from the load behind him. In pa.s.sing oncoming wagons, the drivers tended to keep to the left of the road, again to be able to pa.s.s approaching vehicles as closely as necessary without hitting.

In pa.s.senger carriages, the driver also sat on the right, and the footman, if there was one, sat to the driver's left so that he could quickly jump down and help the pa.s.sengers disembark at the curb.

Needless to say, a coachman wouldn't have felt quite as secure sitting to the right of the driver. Every time a right-handed driver got ready to crack the whip, the coachman would have had to duck and cover.

The British built their cars with the steering wheel on the right because their wagons and carriages at the time still stuck to the left side of the road. Their foot controls, however, have always been the same as American cars.

Well more than a hundred readers sent responses to this Frustable, most of them containing fragments of this explanation. Hopper's article is the best summary of the conventional wisdom on this subject that we have encountered. But there are dissenters. Patricia A. Guy, a reference librarian at the Bay Area Library and Information System in Oakland, California, was kind enough to send us several articles on this subject, including a fascinating one called "The Rule of the Road" from a 1908 periodical called Popular Science Monthly. Its author, George M. Gould, M.D., argues that Americans had adopted right-hand side travel before the development of Conestoga wagons, as had the French, whose wagons were driven by postilion riders (mounted on the left-rear horse). Dr. Gould couldn't come up with a convincing theory for the switch and argued that this Imponderable was likely to be a Frustable for all time.

We include this dissent to indicate that we tend to lunge at any answer that neatly solves a difficult question. We can give you a logical reason why Americans and the French switched the traditional custom of driving on the left; but we wouldn't risk our already precarious reputations on it.

Submitted by Claudia Wiehl of North Charleroi, Pennsylvania. Thanks also to John Haynes of Independence, Kentucky; Kathi Sawyer-Young of Encino, California; Larry S. Londre of Studio City, California; David Andrews of Dallas, Texas; Hugo Kahn of New York, New York; Barbara Dilworth of Bloomsburg, Pennsylvania; Pat Mooney of Inglewood, California; Stephen Murphy of Smithfield, North Carolina; Frederick A. Fink of Coronado, California; and many others.

A free book goes to Richard H. Hopper of Fairfield, Connecticut.

FRUSTABLE 4: Why Is Yawning Contagious?

After the publication of Imponderables, this question quickly became our most frequently asked Imponderable. And after years of research, it became one of our most nagging Frustables. We couldn't find anyone who studied yawning, so we asked our readers for help.

As usual, our readers were bursting with answers, unfortunately, conflicting answers. They fell into three cla.s.ses.

The Physiological Theory. Proponents of this theory stated that science has proven that we yawn to get more oxygen into our system or to rid ourselves of excess carbon dioxide. Yawning is contagious because everybody in any given room is likely to be short of fresh air at the same time.

The Boredom Theory. If everyone hears a boring speech, why shouldn't everyone yawn at approximately the same time, wonders this group.

The Evolutionary Theory. Many readers a.n.a.logized contagious yawning in humans to animals displaying their teeth as a sign of intimidation and territoriality. Larry Rose of Kalamazoo, Michigan, argued that yawning might have originally been a challenge to others, but has lost its fangs as an aggressive maneuver as we have gotten more "civilized."

Several readers pointed us in the direction of Dr. Robert Provine, of the University of Maryland at Baltimore County, who somehow had eluded us. You can imagine our excitement when we learned that Dr. Provine, a psychologist specializing in psychobiology, is not only the world's foremost authority on yawning, but has a special interest in why yawning is contagious! In one fell swoop, we had found someone who not only might be able to answer a Frustable but a fellow researcher whose work was almost as weird as ours.

Dr. Provine turned out to be an exceedingly interesting and generous source, and all the material below is a distillation of his work. As usual, experts are much less likely to profess certainty about answers to Imponderables than are laymen. In fact, Provine confesses that we still don't know much about yawning; what we do know is in large part due to his research.

Provine defines yawning as the gaping of the mouth accompanied by a long inspiration followed by a shorter expiration. This definition seems to support the thinking of some who believe the purpose of a yawn is to draw more oxygen into the system, but Provine disagrees. He conducted an experiment in which he taped the mouths of his subjects shut. Although they could yawn without opening their mouths, they felt unsatisfied, as if they weren't really yawning, even though their noses were clear and were capable of drawing in as much oxygen as if their mouths were open. From this experiment, Provine concludes that the function of yawning is not related to respiration.

In other experiments, Provine has proven that yawning has nothing to do with oxygen or carbon dioxide intake. When he pumped pure oxygen into subjects, for example, their frequency of yawning did not change.

Provine's research also supports the relationship between boredom and yawning. Considerably more subjects yawned while watching a thirty-minute test pattern than while watching thirty minutes of rock videos (although he didn't poll the subjects to find out which viewing experience was more bearable-we wouldn't yawn while watching and listening to thirty minutes of fingernails dragged across a blackboard, either). Did the subjects yawn for psychological reasons (they were bored) or for physiological reasons (boredom made them sleepy)?

When Provine asked his students to fill out diaries recording their every yawn, certain patterns were clear. Yawning was most frequent the hour before sleep and especially the hour after waking. And there was an unmistakable link between yawning and stretching. People usually yawn when stretching, although most people don't stretch every time they yawn.

Yawning is found throughout the animal kingdom. Birds yawn. Primates yawn. And, when they're not sleeping, fish yawn. Even human fetuses have been observed yawning as early as eleven weeks after conception. The child psychologist Piaget noted that children seemed susceptible to yawning contagion by the age of two. It was clear to Provine that yawning was an example of "stereotyped action pattern," in which an activity once started runs out in a predictable pattern. But what's the purpose of this activity?

Although Provine is far from committing himself to an answer of why we yawn, he speculates that yawning and stretching may have been part of the same reflex at one point (one could think of yawning as a stretch of the face). Bolstering this theory is the fact that the same drugs that induce yawning also induce stretching.

The ubiquity of yawning epidemics was obvious to all the people who sent in this Imponderable. Provine told Imponderables, "Virtually anything having to do with a yawn can trigger a yawn," and he has compiled data to back up the contention: 55% of subjects viewing a five-minute series of thirty yawns yawned within five minutes of the first videotaped yawn, compared to the 21% yawn rate of those who watched a five-minute tape of a man smiling thirty times.

Blind people yawn more frequently when listening to an audiotape of yawns.

People who read about yawning start yawning. People who even think about yawning start yawning. Heck, the writer of this sentence is yawning as this sentence is being written.

If we are so sensitive to these cues, Provine concludes that there must be some reason for our built-in neurological yawn detectors. He concludes that yawning is not only a stereotyped action pattern in itself, but also a "releasing stimulus" that triggers another consistently patterned activity (i.e., another yawn) in other individuals. Yawns have the power to synchronize some of the physiological functions of a group, to alter the blood pressure and heart rate (which can rise 30% during a yawn).

Earlier in our evolution, the yawn might have been the paralinguistic signal for members of a clan to prepare for sleep. Provine cites a pa.s.sage in I. Eibl-Eibesfeldt's Ethology, in which a European visitor to the Bakairi of Central Brazil quickly noted how yawns were accepted behavior: If they seemed to have had enough of all the talk, they began to yawn unabashedly and without placing their hands before their mouths. That the pleasant reflex was contagious could not be denied. One after the other got up and left until I remained...

Yet, Provine is not willing to rule out our evolutionary theory either. Perhaps at one time, the baring of teeth sometimes apparent in yawning could have been an aggressive act. Or more likely, combined with stretching, it could have prepared a group for the rigors of work or battle. When bored or sleepy, a good yawn might have revivified ancient cavemen or warriors.

So even if Dr. Provine can't yet give us a definitive answer to why yawning is contagious, it's nice to know that someone out there is in the trenches working full-time to stamp out Frustability. If Dr. Provine finds out any more about why yawning is contagious, we promise to let you know in the next volume of Imponderables.

Submitted by Mrs. Elaine Murray of Los Gatos, California. Thanks also to Esther Perry of Clarks Summit, Pennsylvania; Julie Zumba of Ocala, Florida; Jo Ellen Flynn of Canyon Country, California; Hugo Kahn of New York, New York; Steve Fjeldsted of Huntington Beach, California; Frank B. De Sande of Anaheim, California; Mark Hallen of Irvington, New York; Raymond and Patricia Gardner of Morton Grove, Illinois; Jim White of Cincinnati, Ohio; Renee Nank of Beachwood, Ohio; and many others.

A free book goes to Christine Dukes of Scottsdale, Arizona, for being the first to direct us to Dr. Provine.

FRUSTABLE 5: Why Do We Give Apples to Teachers?

This Frustable has remained remarkably resistant to reasoned replies. Although few readers could supply hard evidence to back their claims, a lot of people sure seemed to think they knew the answer to this one.

Two theories predominated. The most popular answer was the Biblical explanation. In Genesis, the forbidden fruit comes from the tree of knowledge. Although the forbidden fruit is never specified, the apple has over time been given that distinction. As Lou Ann M. Gotch of Canton, Ohio, puts it: the apple has come to signify knowledge. Perhaps by giving an apple to the teacher our children are admitting that they're little devils. Or perhaps they are intimating that the teachers could use a little more knowledge.

The second camp traces the custom to early rural America, when teachers were given free room and board but little pay. Students and their families traditionally brought something to contribute to the school and/or the teacher, be it wood for a fire or fruit for consumption.

But why an apple? As Georgette Mattel of Lindenhurst, New York, points out, apples were cheap and plentiful. Donald E. Saewert adds that the apple is the only fruit that can be stored for long periods of time without canning. In the winter, it might have been the only fresh fruit that was available in many areas. And Ann Calhoun of Los Osos, California, closes this argument with an impressive volley: "Sure would beat dragging a twelve-foot stalk of corn to school."

Both of these arguments are plausible but certainly not proven. Two readers sent us evidence of other possible solutions to this Frustable.

Ann Calhoun mentions that perhaps the apple-teacher connection was made up by an ill.u.s.trator in one of the nineteenth-century ill.u.s.trated magazines ("Every ill.u.s.tration I've seen...includes a very pretty young teacher, a blushing hayseed boy of nine, and a cla.s.sroom of giggling sn.i.g.g.e.rers.") Calhoun speculates that the boy gives the teacher an apple not as a symbol of knowledge but as a symbol of beauty. For according to ancient Greek legend, the highly prized golden apples that grew in the Garden of the Hesperus were awarded for beauty at the Judgment of Paris. Calhoun continues: In every Rockwellian ill.u.s.tration of this theme...the teacher is young and beautiful. Since older generations were heavily schooled in the cla.s.sics (as ours is not) the teacher and kids would get the reference immediately. And yes, there are satiric variations with the teacher depicted as old, fat, gray, ugly, and scowling. The reason for her sour expression is that she also knows the original reference, knows the satiric content of the gesture and is about to send that little hypocritical, mendacious, miscreant presenter out behind the barn for a thrashing he so richly deserves.... I truly can't imagine a spindly young cleric presenting his medieval monkish tutor with an apple for beauty. Such impertinence would only earn him a thrashing outside the castle walls. So when and where did all this apple presenting and polishing start?

Good question. We've heard from only one person who dares to speculate on this. We received a fascinating letter from Henry C. Hafliger, member of the Board of Trustees of the San Jacinto Unified School District. He traces the custom back to Switzerland and cites the book Bauerspiegel, written by Jeremiah Gotthelf in the early nineteenth century. Gotthelf was a disciple of Johann Pestalozzi, the Swiss educator and reformer who had a tremendous influence on American education in the nineteenth century.

In effect, Bauerspiegel chronicles a Swiss equivalent to our rural explanation for the custom. Hafliger summarizes: when education was first offered to all cla.s.ses of children in Switzerland, salaries of teachers were subsistence at best. Parents would supplement teachers' salaries with food, and one of the easiest foods to bring to school was the apple. Farmers would keep apples in their cellars all year long because in those days apples were not considered a dessert but a staple. Gotthelf writes that children soon learned that the child who brought the apple received the least amount of swats with the pointer or switch that the teacher always carried. The children from the poor families, some of whom did not have enough food themselves, were at a distinct disadvantage.

Hafliger's theory, then, was that the fruit was originally given on the premise that "an apple a day keeps the switch away."

Submitted by Malinda Fillingion of Savannah, Georgia. Free books go to Ann Calhoun of Los Osos, California; and Henry C. Hafliger of San Jacinto, California.

FRUSTABLE 6: Why Does Looking up at the Sun Cause Many People to Sneeze?

Of all the Frustables, we came closest to getting a definitive solution to number six. Most of the people who responded were sun-sneezers themselves, and some said that just looking up at a bright light or even at the reflection from a car b.u.mper was enough to set off the achoo mechanism.

The more than one hundred letters we received on this topic almost all carried some variation of the same theme. After a little digging, we found out that the most popular explanation was far from the only possible one.

We do know this much: Somewhere between 25 to 33% of the population is afflicted with "photic sneeze reflex." It is almost certainly a hereditary condition. Reader Margy D. Miller of DeKalb, Illinois, reports that she and all four of her children all sneeze when they first step out of doors into the bright sun.

The most accepted explanation for the photic sneeze reflex is that light signals that should irritate the optic nerves somehow trigger receptors that play a part in the sneezing process. The neural tracts for the olfactory and optic sensory organs lie adjacent to each other and have close (but not identical) insertion points in the brain.

When some people with this particular genetic predisposition encounter a bright light for the first time, the pupils do not contract as rapidly as they should, and the eyes are irritated. Somehow-neurologists we spoke to could not specify how-the olfactory and neural tracts cross-circuit.

The result: The nerves fool the brain into thinking that there is a foreign irritant in the nasal mucosa. The brain does what comes naturally; it tries to rid the sinuses of the phantom dust or pollen. The brain sends out a sneeze reflex.

Case closed?

Not quite. Reader John W. Lawrence, M.D., who specializes in internal medicine and rheumatology, gave us a variation of the above. He concurs that the original cause of the sneeze is eye irritation, but believes that the tears caused by the irritation actually trigger the sneeze: Many people develop eye sensitivity to light. This sensitivity results in a lacrimal outburst (making of excess tears) in response to the irritation. The excess tears then run off down the lacrimal duct, which is present for this purpose. The lacrimal duct empties into the back of the nasopharynx. A drippage of liquid into the back of the nose triggers the sneeze.

Only when tearing exceeds the lacrimal duct's capacity to carry runoff do tears overflow and "run down the cheeks."

William J. Dromgoole, a reader from Somerdale, New Jersey, sent us a newspaper clip indicating that scientists at Scripps Clinic and Research Foundation in La Jolla, California, have found evidence that certain allergy treatments for runny noses can cause photic sneeze reflex. Simply switching medications has rid some people of this mildly vexing problem.

Several readers have written to ask why they always seem to sneeze a particular number of times (sometimes twice, but usually three times). ENT specialists we talked to pooh-poohed it. Anyone have a theory to explain this phenomenon?

Submitted by Rick Stamm of Redmond, Washington. Thanks also to William Debuvitz of Bernardsville, New Jersey; and Lisa Madsden of Minneapolis, Minnesota.

A free book goes to James Miron, R.N., of Republic, Michigan.

FRUSTABLE 7: Why Does the First Puff of a Cigarette Smell Better than Subsequent Ones?

As we indicated in Why Do Clocks Run Clockwise?, the research departments of the major cigarette companies couldn't (or wouldn't) answer this Imponderable. Similarly, the Tobacco Inst.i.tute and the Council For Tobacco Research-U.S.A., Inc., claimed that although much research has been conducted on the sensory awareness of cigarette smoke, this phenomenon was neither universal nor verifiable.

Luckily, Imponderables readers aren't as reticent as the professionals in the field. We don't have a definitive answer to this Frustable, but readers supplied us with three plausible explanations.