Bananas by the Drop

One pound of bananas is that amount of bananas, that is equal in weight to 453.597 cubic centimeters of water, at 0 degrees Celsius when the atmosphere is at 1013.25 millibars of pressure. Of course we all know that 1000 millibars is 1 bar, which is the same as a force of 100,000 Newtons acting on a square meter (and 1 millibar is 100 Pascals). That makes the pound of bananas weigh about 9080 drops of water, give or take a hundred drops. Steve Thoburn should have known that.

Steve Thoburn is guilty of messy measuring and has become a sort of a folk hero in England, where he is called the Metric Martyr. Steve is the owner of a small grocery store, selling fruits and vegetables. When a customer wants a pound of bananas, Steve is happy to comply. But one particular customer was an inspector from the metric brigade and after Steve sold a pound of yellow fruit, he was nabbed for fraud. Steve’s crime was non-adherence to a UK law, passed in 1994 that measurements used in trade must use the metric system. The law came into effect in January 2000.

Steve says he does what his customers wants. And many of the British, especially those belonging to the older generation are much more conversant with pounds and gallons than kilograms and liters. When the Ballards had a new baby, they were told that little Jamie weighed in at 2.548 Kgs. Everyone seems to know that a 9-pound baby is big, a 7-pound baby is lovely and a 5-pound baby is sort of tiny, but what is a 2.548 Kg baby? No idea.

If Steve was a good, honest, law-abiding citizen of Great Britain, he should have done things differently. If an unenlightened customer wanted a pound of bananas, Steve should have placed bananas on his scale till the scale read as close to 454 grams as possible, and then taken the final measure and multiplied it with the price per Kg and divided by 1000 to an accuracy of two decimal places, and then charged the result in Pounds (currency, of course). Instead, Steve stuck some bananas on a scale graduated in pounds, and said the price was 25p. That is an outrageous abomination.

According to the Encyclopedia Britannica, “The British Imperial System evolved from the hodgepodge of Roman, customary, and improvised units employed in the Middle Ages”. Weights are measured in units with strange names such as pounds and ounces while units of length are the mile, furlong, yard, foot and inch. Compounding this mess is that area is measured in hectares and acres and volume in gallons, pints and ounces. In 1824 this system was enacted into law, with definitions such as “a gallon is equal in volume to 10 pounds avoirdupois of distilled water weighed at 62 F with the barometer at 30 inches of mercury”. A much more unified, simple to comprehend, easier to convert method of measurement is the “right way” and such a way is the metric system.

Steve Thoburn went on trial for illegal trade practices. The UK is part of the European Union, which mandates all members must follow the metric system. The weight of the law is not quite uniform. While kilograms and liters have to be used for groceries, distance is still measured in miles, and the speed limits on the roads read miles/hour. Of course, such is not the case in the rest of Europe, where everything is metric. Makes you wonder how many seconds there are in a French minute.

The French, just after the French Revolution of 1789 had started pursuing the idea of using metric for all weights and measures. The meter was to be 1/10,000,000 of the circumference of the Earth, and 1/100 of the meter would be the centimeter, and a cubic centimeter of water at freezing point (0° C) would be 1 gram. This unified length with weight with temperature (freezing and boiling of water are 100° apart). Thus this system was deemed to be modern, well thought through and the way we humans should measure things.

The first success of the metric system was money. People took to dividing money into hundreds like fish to water. Even the British with a long history of 12 pence to a shilling and 20 shillings per pound, found no problem in dumping that for 100 pence to a pound. The idea started in 1965 and was in widespread acceptance in 1971. Even earlier, in 1957 India did away with the rupee-anna-paisa-pie system for the Rupee-paisa metric system.

The trial of Steve Thoburn lasted 6 days (or should I say 0.857 week?). It was 6 days of a media circus, combined with the British outrage at foreign intervention between an honest guy and his banana trade. The prosecution declared, “It is imperative that this court finds Steve Thoburn ‘Guilty’.   This is part of the legal framework of the European Union. If Steve Thoburn is found ‘Not Guilty’, Britain's position within the European Union would be untenable, and Britain would have to leave." Of course, membership in the EU is much more weighty than 454 grams of bananas, and Mr. Thoburn was fined over 60,000 units of currency.

While currency is universally metric, the changeover to metric of measures have not been very rosy. By law, all countries of the world with the notable exception of Liberia, Myanmar and the USA have abolished the use of other forms of measurements. In the US, the adoption of the metric system has never had much of a following. In 1821 Secretary of State John Quincy Adams, in a famous report to the US Congress, called the metric system “worthy of acceptance . . . beyond a question.” In 1866 the US passed the Metric Act, which made the use of the metric system legal (but not mandatory). The scientific community, some politicians and some concerned citizens bring up the metric conversion routinely but no one pays it much attention.

After all, what can be simpler than buying a gallon of gasoline for one dollar? It is a great yardstick (sorry, meter-stick). If the price is much above a dollar, it is time for concern, if it is lower than a dollar it is time to party. The British system is kind of ingrained into much of our lives, especially in the US. A tall person is over 6 feet high and should weigh about 200 pounds. The same person at 182.9 cm tall and 90 Kgs hardly makes an impression. When the temperature rises above 100° F, a record book entry of a “triple-digit day” is created. The same temperature in metric is 37.8° C, hardly something memorable. A human armpit should be at 97.5° F and if the thermostat rises above 100° F it is time for concern.

While the metric system definitely has its strong points the measurements we all use all the time are hardly metric. Every second of every day adds up to 1/60^th of a minute, and and 60 minutes make an hour which is 1/24^th of a day. Seven days make up our week and there is no integral number of weeks in a month, which varies inexplicably between 28 and 31 days. No one in his or her right mind has ever proposed a 10-day week or a 100-day month.

The British system is quirky in the when we use different units for the same thing (or same units for different things), and they are not divisible by 10. For example, 16 ounces make a pound (two units for weight) but 128 ounces make a gallon for volume. The US subterfuged the Imperial system by decimalizing it. We do not buy 1 gallon and 23 ounces of gasoline—we buy 1.18 gallons. Similarly, pounds and ounces are almost never mixed up; they are expressed in decimal forms and weight is almost always expressed in pounds (not ounces). As long as there is one dominant unit of measurement there is hardly any confusion. The strength of the metric system is the unification—the weight and the volume is related via water (1cc of water is a gram). This connection, though somewhat important in science and engineering has hardly much of a part to play in everyday life, where we have much more of a hassle figuring out the difference in days between 20 weeks and 5 months (there is no correct answer). Yet the metric system fails the unification test, as the ultimate speed—the speed of light is 299,792,458 m/s.

One of the most confusing arenas of units of measurements is in aviation, where ironically, the safety of life depends on measurements. Distance is measured in nautical miles and speed is measured in knots (1 knot = 1 nautical mile per hour). Yet visibility is measured in statute miles and elevation is measured in feet. Weight and volume correlation is also important—when an aircraft is loaded with 100 gallons of fuel we must know what the fuel weighed (so we memorize—6 pounds make a gallon). Air pressure is often in inches of mercury but sometimes in millibars. What is the conversion between nautical and statute miles, in feet? No idea.

The Metric system does away with the old hodgepodge of pounds-ounces-pints-gallons-acres-hectares-farthings-furlongs-farenheits and replaces it with a sensible, scientific system of meters, grams and seconds, along with prefixes such as peta-giga-mega-kilo-deca-centi-milli with some added fun stuff like bars, pascals, newtons, ohms, amperes, hertz and volts. Computers make it more fun, a kilobyte is not 1000 bytes, it is 1024 bytes, and a megabyte is 1024 kilobytes—go figure.

We must thank the French for their enormous contribution to humanity for clearing up the mess in measurements. The only problem is that the French vow never to come to closure on consistency in correlation of spelling with pronunciation.

Partha Dasgupta is on the faculty of the Computer Science and Engineering Department at Arizona State University in Tempe. His specializations are in the areas of Operating Systems, Cryptography and Networking. His homepage is at http://cactus.eas.asu.edu/partha