“A scientific Christmas is a memorable Christmas,” I wrote last week in my column on scientific gifts. But it occurred to me, post-column, that shopping for Christmas gifts involves science even if all you’re buying is a tie for Dad.
Consider, for example, the music playing in the store. The best known source for store music is the Muzak Corporation, whose arrangements of familiar songs are specifically designed to be pleasant, but not intrusive; literally, “audio wallpaper.”
Muzak is broadcast on its own frequency as a coded radio signal. Stores that subscribe to the service receive a signal decoder. Muzak Corporation has been around for 60 years, and scientific studies on the effects of music on workers and shoppers date back almost that far. Psychologists have found that people work harder and suffer less stress when they listen to certain kinds of music. (This doesn’t apply to all music; a store that chooses to play, say, Bony M’s “Mary’s Boy Child” over and over should be subjected to a letter-writing campaign by Amnesty International to halt its cruel and unusual punishment of employees and shoppers alike.)
Studies also show that the right music can boost sales: people walk slower, stay longer and therefore shop more in stores that play not-too-fast, unobtrusive music–like Muzak. (Fast, hard-driving music actually drives people out of stores by making them walk faster.) At Christmas, another element enters in: that familiar Christmas music playing in the background is supposed to trigger your annual gift-buying frenzy.
Let’s say it’s worked. You’ve found the perfect knick-knack for Aunt Sally: one of those snowstorm-in-a-glass-ball thingies with a model of the Legislative building inside it, complete with teeny-tiny MLAs standing on the steps. What you don’t find is a price tag: instead, the price is indicated on a label on the shelf. The only thing on the knick-knack itself is a little box with a bunch of black bars of varying thicknesses inside it.
This is the “bar code.” It may not mean much to you, but it means lots to a computer. The cashier either passes it over the glass plate of a scanner built into the counter or runs a hand-held scanner over it. These scanners use lasers to read the code into the computer. Computers encode information in binary form–as a series of ones and zeroes, or “ons” and “offs.” The laser is reflected from the white parts of the bar code back to a photoelectric cell, registering an “on,” or one, and isn’t reflected from the black parts of the bar code, which register as “offs,” or zeroes. The resulting string of ones and zeroes tells the computerized cash register where to look in its memory for the price of the object.
The cashier informs you your Leg-in-a-snowstorm-knick-knack costs $259.26, plus, of course, GST and PST. Since you only have three dimes, a nickel, fourteen pennies and a lint-covered Lifesaver in your pocket, you blanche and reach for plastic.
But which form of plastic so you use–your credit card or your bank card? (Or maybe your Health Services Card, if the quoted price has given you palpitations.) Science cannot help you with this decision, because technically, what happens next is about the same whichever card you use.
Each card has a magnetic strip on its back, on which is recorded account data and a personal identification number. The clerk passes the card through a device which reads this information and automatically makes a phone call to your bank’s computer to see if you have enough credit or enough money to cover the transaction. If you’re making a direct payment from your account, you also have to authorize the transaction with your personal identification number. All this happens in seconds, even though the computers involved can be provinces apart..
The direct payment from account option is relatively new. Credit Unions have had debit cards for some time, but direct payment through Interac (an association of 28 financial institutions across Canada) has only been available in Saskatchewan since September of 1993. In little more than a year there have been more than two million direct-payment transactions in this province, with a total value around $100 million. That’s about 5,500 Interac transactions, worth $250,000, daily. Debit cards seem to be a technology that really serves a need–especially at Christmas.
Of course, you might have paid for your knick-knack in…what’s that stuff called?…oh, yeah, “cash,” but if you did, you probably got that cash from an automated teller machine, another technological invention it’s hard to imagine we ever got by without. It, too, uses the ubiquitous plastic card, but since the ATM is connected directly to your bank’s computer and also contains a quantity of cash, it can offer you more services.
It’s ironic that Don Wetzel, the Texan who invented the ATM in 1968, never made any money from his brainchild. Interac cardholders alone made over 780 million withdrawals from more than 15,500 banking machines in 1993. Wetzel should have figured out a way to have one cent of every transaction forwarded to his own account!
One way or another, you’ve paid for your knick-knack and made it out of the store. But your legs ache (due to a build-up of lactic acid, produced by hardworking muscles as a by-product of the metabolizing of sugar in the absence of oxygen), so you decide to head for home.
On the way out to the car, you may run afoul of one more bit of science: the fascinating fact that ice, which is already slippery simply because its smooth, melts a little bit when you put pressure on it. The resulting thin layer of water makes it even slipperier. And since, of course, you’re already off-balance due to juggling both Aunt Sally’s knick-knack and fourteen other presents, you are susceptible to “losing your balance”–which happens when your foot slips so far that your centre of gravity is no longer supported by your legs–and “falling”–caused by the attractive force exerted by the mass of the planet on your body and your packages.
Should such misfortune be your lot, it may perhaps ease the pain to reflect on how elegantly you have demonstrated a basic scientific principle to whomever may be watching.