When Do Fish Sleep? (26 page)

The unromantic explanation (a.k.a. the truth) is as follows: Once your ticket form is torn by the ticket agent, it is sent to the accounting department of the airline. The major carriers have long used optical scanners to read the serial numbers found on each ticket. An OCR (Optical Character Recognition) scanner can’t read the ticket when black flecks of carbon land on the serial number because it can only register information printed in black ink. Much as a photocopier will not read blue ink, an OCR scanner won’t read red ink. Who would have thought that accountants would be responsible for the daring flash of red on airline tickets?

In a time of high-tech stationery, why don’t the airlines use carbonless paper? Part of the answer again relates to the OCR equipment. Carbonless paper contains blue specks that OCRs won’t read. Furthermore, with chemically sensitized noncarbon paper, legibility is good for only about five copies. Old-fashioned carbon paper can render nine legible copies, sometimes necessary for the daunting itineraries of business travelers.

Now that most airlines are issuing automated ticket boarding passes—the ones that look like computer cards—the decline of the carbonized form is inevitable. Because not all ticket counters possess the equipment to issue these boarding passes, Mr. George predicts that the beloved red carbonized forms will continue to play a part in aviation for the foreseeable future.

Submitted by Niel Lynch of Escondido, California
.

I
Have a Dollar Bill with an Asterisk After the Serial Number: Is It Counterfeit?

The
Imponderables
staff will gladly accept your dollar bill if you don’t want it. No, it’s not counterfeit. You are holding a “star note,” a replacement for a defective bill that has been destroyed.

In 1910, the Bureau of Engraving and Printing started printing
B and later
D as prefixes before the serial numbers of replacement notes. No star notes were issued for national bank notes, which were replaced by new notes that matched the missing serial numbers.

Now that notes are issued in series of one hundred million at a time, it is obvious why the Bureau would rather not have to renumber replacement notes, especially since, as Bob Cochran, secretary of the Society of Paper Money Collectors, told us, errors are quite common in the printing process:

The most common errors are in inking, cutting, and in the overprinting operation. With inking there can be too much, not enough, or unacceptable smears. Notes are printed in sheets of 32; the back is printed in all green ink and then the face is printed in all black ink. If one side or the other is not registered properly, the designs will not match up on both sides after the sheets are cut up; if the registration is very poor, the notes will be replaced. A third separate printing operation adds the serial number and Treasury Seal; the major error possibilities are in inking and placement, since the basic note design already exists at this point.

You have probably noticed that serial numbers on U.S. currency are preceded by a letter. That letter designates which of the twelve Federal Reserve districts issued the note (this is why the letters span A through L). For example, all serial numbers preceded by D (the fourth letter of the alphabet) are issued by the Fourth District of the Federal Reserve (Cleveland). Here is a list of the twelve Federal Reserve Bank districts and the letter designations for each:

The star note enables the treasury to issue a new set of serial numbers rather than attempting to reassign all the missing serial numbers of defective notes. On U.S. notes, a star substitutes for the prefix letter. A replacement U.S. note might look like this:
00000007 B. On Federal Reserve notes, a star substitutes for the letter at the end of the serial number, so that the location of the Federal Reserve district is kept intact: D 00000007
.

William Bischoff, associate curator of the American Numismatic Society, adds that there is one other use for the star note. The Bureau of Printing and Engraving uses printers with eight-digit numbering cylinders to produce one hundred million notes at a time. But for the one-hundred-millionth note, a ninth digit is needed. Rather than bothering to add another digit on the cylinder that would literally be used on one out of a hundred million notes, the one-hundred-millionth note is a hand-inserted star note.

To
What Do the Numbers Assigned to Automotive Oil Refer?

Thirty years ago, 10-30 was considered a premium automotive oil. Today, one can buy 10-50 or even 10-60 oil, but few people know what these numbers mean.

The numbers measure the viscosity of the oil. The higher the number, the higher the viscosity (meaning the oil is less likely to flow). Although the viscosity of a liquid is not always directly correlated to thickness, high-viscosity oils are thicker than their low-viscosity counterparts.

The numbers on engine and transmission oils are assigned by the Society of Automotive Engineers. Their numbers range from 5W to 60. The W stands for winter. When a W follows a number, it indicates the viscosity of the oil at a low temperature. When there is no W following a number, the viscosity is measured at a high temperature.

All oil companies promote multigrade oils, which are designed to perform well in hot or cold temperatures. Thus 10W-40 doesn’t indicate a range of viscosity, but rather the low viscosity of oil during winter (when one desires greater flow capabilities) and high viscosity in the summer.

Submitted by Tom and Marcia Bova of Rochester, New York
.

When
I Put One Slice of Bread in My Toaster, the Heating Element in the Adjacent Slot Heats Up as Well. So Why Does My Toaster Specify Which Slot to Place the Bread in If I Am Toasting Only One Slice?

Considering that the pop-up toaster has proven to be perhaps the most durable and dependable kitchen appliance, we were surprised to learn that toasting technology varies considerably from model to model. The earliest toasters browned one side of bread at a time; one had to decide when to flip the bread over by hand, a problem not unlike the momentous decision of when to flip over a frying pancake or hamburger.

Now that even the simplest pop-up toaster has a toast selector dial to allow the user to choose the preferred degree of doneness, most of the guesswork in toasting has been eliminated. We are not even allowed to select which of two or four slots to put in our one meager slice of bread. Why not?

Actually, nothing dire will result if you don’t use the slot marked
ONE SLICE
. The worst that will happen is that the toaster will pop up an underdone or overdone piece. But why is the same well that manages to produce wonderful toast when it has company next door suddenly rendered incompetent when forced to work alone?

The answer depends upon the type of technology the toaster uses to determine doneness. The simplest toasters, now passé, worked from a simple time principle. The darker the brownness dial was set for, the longer the timer set for the toaster to heat the bread. Toasters that worked on a timer alone did not need a
ONE SLICE
notation because they always cooked the bread for the same amount of time, as long as the brownness dial wasn’t changed. Using a timer alone guaranteed that a second set of toast would come out overdone, because the toaster was already warmed up yet toasted the second set for the same period of time as the first batch that was heated from a “cold start.”

To solve the problem, appliancemakers inserted a thermostatic switch in toasters, which measured the heat of the toaster rather than the time elapsed in cooking. The thermostat alone caused a reverse problem. A second batch of bread would come out underdone because the first cycle had already caused the heating element to charge. The toaster didn’t “know” that the second batch of bread hadn’t been exposed to the toaster long enough; it knew only that the toaster had achieved the desired temperature.

The solution to the problem was to use a combination timer-thermostat. Today, the timer is not set off until the thermostat tells the timer that the toaster has reached the preset temperature (determined by the setting of the brownness dial). With this technology, it might take a minute for the thermostat to tell the timer to start ticking with the first set of toast but only a few seconds for the second or third.

We spoke to an engineer at Proctor-Silex who told us that most of their toasters have the thermostat close to—or in some cases, inside—the well that is marked
ONE SLICE
so the thermostat can do a more accurate job of “reading” the correct temperature for that slice. Some toasters that have
ONE SLICE
markings are “energy saver” toasters, specifically designed so that the heating element in the second slot will not be charged if it does not contain bread.