The study of chewing sounds is a very specialized field. (For an extreme example, see ‘Crisp Sounds’ on page 138.) The field apparently acquired a name in 1966, when British dentist D. M. Watt published a paper called ‘Gnathosonics: A Study of Sounds Produced by the Masticatory Mechanism’.
Amft, Stäger, Tröster, and Lukowicz are proud of their chew-sound-analysis achievement. But mindful of technology’s limits, they aim to keep their aims simple. In their words: ‘The system does not need be fully automated to be useful ... it is perfectly sufficient if at the end of the day the system can remind the user that for example “at lunch you had something wet and crisp (could have been salad) and some soft texture stuff (spaghetti or potatoes)” and asks him to fill in the details.’
Amft, Oliver, Mathias Stäger, Paul Lukowicz, and Gerhard Tröster (2005). ‘Analysis of Chewing Sounds for Dietary Monitoring.’ UbiComp 2005: Proceedings of the 7th International Conference on Ubiquitous Computing, Tokyo, Japan, 11–14 September: 56–72.
Drake, B. K. (1963). ‘Food Crushing Sounds: An Introductory Study.’ Journal of Food Science 28 (2): 233–41.
Watt, D. M. (1966). ‘Gnathosonics: A Study of Sounds Produced by the Masticatory Mechanism.’ Journal of Prosthetic Dentistry 16 (1): 73–82.
Pour Laws
When physics professors take to the bottle, they can be tenacious about it. Take Christophe Clanet and Geoffrey Searby, who wrote a highly condensed, fourteen-page report called ‘On the Glug-Glug of Ideal Bottles’, which was published in the Journal of Fluid Mechanics. Like so much of the literature emerging from Europe during the past two centuries, this study celebrates what happens when liquid is poured from a container.
The pair of de-bottling experts is based at the Institut de Recherche sur les Phénomènes Hors Equilibre in Marseille, France. Both men are fascinated by bubbles and motion. Searby heads a French–German committee doing research on rocket engine combustion, while Clanet has become tops in the physics subspecialty of skipping stones across ponds.
‘Glug-glug’ is now a technical term, thanks mostly to Clanet and Searby. They tried it out at a physics conference in 1997, presenting a talk called, plainly, ‘On the Glug-Glug of the Bottle’. Their opening words were circumspect: ‘We study experimentally the emptying of a vertical cylinder of diameter D and length L.’ The audience response was such that Clanet and Searby continued their exploration of glug-glugs. They delved into the theoretical aspects, as well as the empirical.
Their follow-up paper begins with a dramatic sentence: ‘An image of life is a return to the thermodynamic equilibrium of death via the oscillations of our heartbeats.’ Then, with a quick literary pirouette, they describe the ‘onomatopoeic glug-glug’ of an emptying bottle. ‘This oscillatory behaviour’, they remind us, ‘starts at the opening and continues until the bottle is empty.’
The apparent weight of the bottle lurches way up and slightly less down, up, down, up, down, until the liquid is gone. Clanet and Searby produced a graph of this behaviour, a visual form of glug-glug that some scientists find as delightful as the sound.
The experiment involved Newtonian liquid, a tank, two valves, a pump, a pressure sensor, a camera, and a laser beam. It built upon the pioneering bubble-behaviour work done in the late 1940s by Geoffrey Taylor at the University of Cambridge. Taylor’s bubbles inspired a ragged, international line of experimentation on bottle-emptying that culminated with the Clanet/Searby glug-glug work.
The fruits of the experiment are sweet. Through painstaking work, Clanet and Searby elucidated the basic law of glug-glug: the time needed to empty a bottle depends on the diameter of the bottle, and also on the diameter of the hole.
Of course, this is the law for an idealized bottle shape – a can rather than the beloved Coca-Cola bottle or other quirky form. Even for a Coke can, though, there remains the open question of the tab-shaped opening. Clanet and Searby used a cylinder with a circular hole. Whether and how much a different hole shape affects the glug-glug is, almost needless to say, a matter for further research.
Clanet, Christophe, and Geoffrey Searby (2004). ‘On the Glug-Glug of Ideal Bottles.’ Journal of Fluid Mechanics 510: 145–68.
Clanet, C., G. Searby, and E. Villermaux (1997). ‘On the Glug-Glug of the Bottle.’
American Physical Society, Division of Fluid Dynamics Meeting, 23–25 November, abstract #Df.10.
Davies, R. M., and Geoffrey Taylor (1950). ‘The Mechanics of Large Bubbles Rising Through Liquids and Through Liquids in Tubes.’ Proceedings of the Royal Society of London, Series A 200 (22 Feb): 375–90.
The Repetitive Physics of Om
Two Indian scientists are wielding sophisticated mathematics to dissect and analyse the traditional meditation chanting sound ‘Om’. The Om team has published six monographs in academic journals. These plumb certain acoustic subtleties of Om, which the researchers say is ‘the divine sound’.
Om has many variations. In a study published in the International Journal of Computer Science and Network Security, the researchers explain: ‘It may be very fast, several cycles per second. Or it may be slower, several seconds for each cycling of [the] Om Mantra. Or it might become extremely slow; with the mmmmmm ... sound continuing in the mind for much longer periods, but still pulsing at that slow rate. It is somewhat like one of these vibrations:
OMmmOMmmOMmm ...
OMmmmmOMmmmmOMmmmm ...
OMmmmmmmmOMmmmmmmmOMmm
The important technical fact is that no matter what form of Om one chants at whatever speed, there is always a basic Omness to it.
Ajay Anil Gurjar and Siddharth A. Ladhake published their first Om paper, titled ‘Time-Frequency Analysis of Chanting Sanskrit Divine Sound “OM”’, in 2008. Ladhake is the principal at Sipna’s College of Engineering and Technology in Amravati, India. Gurjar is an assistant professor in that institution’s department of electronics and telecommunication. Both specialize in electronic signal processing. They now subspecialize in analysing the one very special signal.
In their introductory paper, Gurjar and Ladhake explain (in case there is someone unaware of the basics) that: ‘Om is a spiritual mantra, outstanding to fetch peace and calm. The entire psychological pressure and worldly thoughts are taken away by the chanting of Om mantra.’
No one has explained the biophysical processes that underlie this fetching of calm and taking away of thoughts. Gurjar and Ladhake’s time-frequency analysis is a tiny step along that hitherto little-taken branch of the path of enlightenment.
They apply a mathematical tool called wavelet transforms to a digital recording of a person chanting ‘Om’. Even people with no mathematical background can appreciate, on some level, one of the blue-on-white graphs included in the monograph. This graph, the authors say, ‘depicts the chanting of “Om” by normal person after some days of chanting’. The image looks like a pile of nearly identical, slightly lopsided pancakes held together with a skewer, the whole stack lying sideways on a table. To behold it is to see, if nothing else, repetition.
At the end, Gurjar and Ladhake write: ‘Our attentiveness and our concentration are pilfered from us by the proceedings take place around us in the world in recent times ... By this analysis we could conclude steadiness in the mind is achieved by chanting OM, hence proves the mind is calm and peace to the human subject.’
Much as people chant the sound ‘Om’ over and over again, Gurjar and Ladhake repeat much of the same analysis in their other five studies, managing each time to chip away at some slightly different mathematico-acoustical fine point.
Gurjar, Ajay Anil, and Siddharth A. Ladhake (2008). ‘Time-Frequency Analysis of Chanting Sanskrit Divine Sound “OM”.’ International Journal of Computer Science and Network Security 8 (8): 170–75.
–– (2009). ‘Spectral Analysis of Sanskrit Divine Sound OM.’ Information Technology Journal 8: 781–85.
–– (2009). ‘Optimal Wavelet Selection For Analyzing Sanskrit Divine Sound “OM”.’ International J
ournal of Mathematical Sciences and Engineering Applications 3 (2): 225–33.
–– (2009). ‘Analysis of Speech Under Stress Before and After OM Chant Using MATLAB 7.’ International Journal of Emerging Technologies and Applications in Engineering, Technology and Sciences 2 (2): 713–18.
–– (2009). ‘Time-Domain Analysis of “OM” Mantra to Study It’s [sic] Effect on Nervous System.’ International Journal of Engineering Research and Industrial Applications 2 (3): 233–42.
Gurjar, Ajay Anil (2009). ‘Multi-Resolution Analysis of Divine Sound “OM” Using Discrete Wavelet Transform.’ International Journal of Emerging Technologies and Applications in Engineering, Technology and Sciences 2 (2): 468–72.
Gurjar, Ajay Anil, Siddharth A. Ladhake, Ajay P. Thakare (2009). ‘Analysis of Acoustic [sic] of “OM” Chant to Study It’s [sic] Effect on Nervous System.’ International Journal of Computer Science and Network Security 9 (1): 363–67.
Humming in the Key of Bee
Norman E. Gary is the rare academic who plays clarinet while he is covered with live bees, and often does so in public.
An emeritus professor of apiculture at the University of California (Davis), Gary also plays Dixieland music in a human ensemble called the Beez Kneez Jazz Band. He generally goes solo – he alone with his instrument – for the bee-encrusted gigs.
Hollywood has used Gary’s bee-wrangling talents and sometimes his acting ability, though seldom his clarinet, in more than a dozen films. Among them: The X Files, Fried Green Tomatoes, Invasion of the Bee Girls, and Candyman: Farewell to the Flesh.
Several of Gary’s scientific activities involve vibration, a general physics phenomenon of which music is just a part. He has microwaved bees. He has also analysed one of the lesser-known (to most humans) sounds that bees produce. Details appear in a 1984 monograph published with colleague S. S. Schneider in the Journal of Apicultural Research. They gave their article the title ‘“Quacking”: A Sound Produced by Worker Honeybees after Exposure to Carbon Dioxide’.
Gary has vacuumed bees. He has also made it easier and more efficient for others who want or need to vacuum the insects, by inventing a purpose-built bee vacuum with his colleague Kenneth Lorenzen. The wording in their patent could, with a bit of work, be set to hummable music: ‘By the operation of the mechanism in the fashion disclosed, the bees on the opposite sides of a comb, and eventually of a plurality of combs and frames, are removed therefrom by a concomitant vacuuming and brushing operation.’
The professor has published more than one hundred academic papers, many of them about bees. In one of the earliest, called ‘The Case of Utter vs. Utter’, he took a fond look back at a court case decided in 1901 in Goshen, New York, starring two brothers from a family named Utter.
The brothers disagreed – Utterly, of course – about many things. The question here was: did the bees associated with one brother, a beekeeper, eat the peaches growing on trees owned by the other brother, a fruit grower? Perhaps the most enjoyable account appeared soon after the trial, in the Rocky Mountain Bee Journal. The anonymous writer says: ‘It was amusing to see the plaintiff try to mimic the bee, on the witness stand as he swayed his head from one side to the other, raised up on his legs and flopped his arms. His motions were so utterly ridiculous and so contrary to the real acts and achievements of the bees, that everyone in the courtroom, including the jury, laughed, and laughed heartily.’
The court ruled against that Utter, and for the other. This established a legal precedent favourable to wandering bees. It also inspired, almost sixty years later, the young Norman Gary as he began his more-than-sixty-year-long career of collaborating with and studying tiny, honey-making musicians.
Schneider. S. S., and Norman E. Gary (1984). ‘“Quacking”: A Sound Produced by Worker Honeybees After Exposure to Carbon Dioxide.’ Journal of Apicultural Research 23 (1): 25–30.
Gary, Norman E., and Kenneth Lorenzen (1981). ‘Bee Vacuum Device and Method of Handling Bees.’ US Patent no. 4,288,880.
Gary, Norman E. (1959). ‘The Case of Utter vs. Utter.’ Gleanings in Bee Culture 87 (6): 336–37.
N. A. (1901).‘Bees in Court: History of the Celebrated Case of Peach Utter versus Bee-Keeper Utter.’ Rocky Mountain Bee Journal 1 (1): 6.
Vacuum Travel
The journey between London and Edinburgh would be much quicker had the London and Edinburgh Vacuum Tunnel Company been allowed and able to build a breathtaking new piece of technology, back when land was cheap and all things seemed possible. The 29 January 1825 issue of the Mechanics Register presents the scheme in detail: ‘The London and Edinburgh Vacuum Tunnel Company is proposed to be established, with a capital of Twenty Millions Sterling, divided into 200,000 shares, of £100 each, for the purpose of forming a Tunnel or Tube of metal between Edinburgh and London, to convey Goods and Passengers between these cities and the other towns through which it passes.’
The plan is simple. There are two long tunnels or tubes, side by side, one reserved for trips northbound to Edinburgh, the other for London-bound traffic. Boilers, located every two miles along the approximately 390-mile length of the tunnel or tube, supply steam that, through a clever bit of engineering, creates a vacuum.
At departure time, the vacuum seal is broken at the departure end, right behind the train. Thanks to the difference in pressure, the train is thus immediately impelled into the tunnel or tube.
To maintain pressure all through the journey, to keep a tight seal behind the train, there’s a ‘very strong air-tight sliding door, running on several small cylindrical rollers, to lessen the friction’. The inrushing air pushes the slick-sliding door. That whizzing, roller-riding door pushes the amassed railway cars onwards, onwards, faster and faster into the airless tunnel or tube.
These cars carry only freight. People never enter the tube, which, being four feet tall, is too short for most of them.
Passengers instead ride in traditional railway carriages on tracks affixed on top of the tunnel or tube. These passenger cars are coupled by strong magnets to the freight-carrying cars. As the freight train zooms through the tunnel or tube, its magnetic field drags the passenger train along on what is sure to be a rapid and exciting ride. The acceleration is such that the train travels ‘altogether, in the first five minutes’ of its journey, ‘480 miles 4448 feet’.
This would have been a considerable advance over the standard railway capabilities of the time. A dispatch in the same issue of the Mechanics Register allows that ‘the practicality of [conventional] steam carriages for the conveyance of passengers is fully established, and we have as little doubt that the conveyance of goods at the rate of seven or eight miles an hour, will soon be as easily accomplished’.
The London and Edinburgh Vacuum Tunnel Company report is accompanied by a small notice: ‘The foregoing Jeu d’Esprit appeared in a recent number of the Edinburgh Star, and being well calculated to throw ridicule upon some of the preposterous plans now before the public for the investment of money, we insert it in the Register.’
Nonetheless, in subsequent decades, engineers in Ireland, America, and Britain did build short stretches of pneumatic passenger railway. None spanned great distances or lasted more than a few years. Isambard Kingdom Brunel, designer of England’s first great railways (and of London’s Paddington station), built about twenty miles of pneumatic railway between Exeter and Newton before abandoning it as impractical.
N. A. (1825). ‘London and Edinburgh Vacuum Tunnel Company, Capital 90,000 Sterling.’ Mechanics Register 1 (13): 205–7.
May We Recommend
‘Effects of Horizontal Whole-Body Vibration on Reading’
by Michael J. Griffin and R. A. Hayward (published in Applied Ergonomics, 1994)
Very Special Topics
The global nature of football (a/k/a soccer in the US) varies measurably from city to city because of down-to-Earth differences in the air pressures, temperatures, and other physical conditions. But those differences are slight in compariso
n to the ones described in a University of Leicester study called ‘Association Football on Mars’.
Calum James Meredith, David Boulderstone, and Simon Clapton published the analysis in the university’s Journal of Physics Special Topics, which takes up topics that seldom find their way into the better-known physics journals. The journal is produced by and for university students, which makes it a bit unusual. Its unusualness quotient increases with the knowledge that the current head of the department of physics and astronomy at the University of Leicester is Professor Lester.
‘Association Football on Mars’ methodically calculates the altered basics of play on the red planet. ‘It would be possible to retain the game in a familiar but slightly changed form’, the authors say.
On the Martian surface, the gravitational pull and the air pressure are less than we’re used to. The ball would encounter substantially less drag in its journeying from foot to foot to head to foot to goal. On many a kick, the ball would travel about four times as far as it would on Earth. These impressive distances come with a straightforward cost: ‘the inability to “bend” the ball due to a lack of air resistance would seem to decrease the skill involved in football’.
Height vs. distance for footballs kicked on Earth (solid line) and Mars (dashed line)
In the same issue of the journal, one finds other monographs by the team of Meredith, Boulderstone, and Clapton. Two of those consider a solution to our era’s most pressing environmental problem.
In ‘None Like It Hot’, the trio propose and describe a method ‘to help combat global warming by moving the Earth further [sic] away from the Sun to reduce its surface temperature’. A companion paper, ‘None Like It Hot II’, investigates whether this feat ‘would be plausible given conventional rocket technology’. They conclude that the mass of fuel needed to perform the manoeuvre ‘is only a few orders of magnitude smaller than the mass of the Earth. The number of rockets will make only a small difference due to the nature of the relationship between the two values.’
This is Improbable Page 5
