Why do Clocks run clockwise? (26 page)

“meter,” which is an Americanized version of what most of the world—including other English-speaking countries—spells “metre.”

Why Does the Moon Appear Bigger at the Horizon
Than Up in the Sky?

This Imponderable has been floating around the cosmos for eons and has long been discussed by astronomers, who call it the moon illusion. Not only the moon but the sun appears much larger at the horizon than up in the sky. And constellations, as they ascend in the sky, appear smaller and smaller. Obviously, none of these bodies actually changes size or shape, so why do they
seem
to grow and shrink?

202 / DAVID FELDMAN

Although there is not total unanimity on the subject, astronomers, for the most part, are satisfied that three explanations answer this Imponderable. In descending order of importance, they are: 1. As Alan MacRobert of
Sky & Telescope
magazine states it, “The sky itself appears more distant near the horizon than high overhead.”

In his recent article in
Astronomy
magazine, “Learning the Sky by Degrees,” Jim Loudon explains, “Apparently, we perceive the sky not as half a sphere but as half an oblate [flattened at the poles]

spheroid—in other words, the sky overhead seems closer to the observer than the horizon. A celestial object that is perceived as ‘projected’ onto this distorted sky bowl seems bigger at the horizon.”

Why? Because the object appears to occupy just as much space at the seemingly faraway horizon as it does in the supposedly closer sky.

2. When reference points are available in the foreground, distant objects appear bigger. If you see the moon rising through the trees, the moon will appear immense, because your brain is unconsciously comparing the size of the object in the foreground (the tree limbs) with the moon in the background. When you see the moon up in the sky, it is set against tiny stars in the background.

Artists often play with distorting perception by moving peripheral objects closer to the foreground. Peter Boyce, of the American Astronomical Society, adds that reference points tend to distort perception most when they are close to us and when the size of the reference points is well known to the observer. We
know
how large a tree limb is, but our mind plays tricks on us when we try to determine the size of heavenly objects. Loudon states that eleven full moons would fit between the pointer stars of the Big Dipper, a fact we could never determine with our naked eyes alone.

3. The moon illusion may be partially explained by the refraction of our atmosphere magnifying the image. But even the WHY DO CLOCKS RUN CLOCKWISE? / 203

astronomers who mentioned the refraction theory indicated that it could explain only some of the distortion.

A few skeptics, no doubt the same folks who insist that the world is flat and that no astronaut has ever really landed on the moon, believe that the moon really
is
larger at the horizon than when up in the sky. If you want to squelch these skeptics, here are a few counterarguments that the astronomers suggested.

1. Take photos of the moon or sun at the horizon and up in the sky. The bodies will appear to be the same size.

2. “Cover” the moon with a fingertip. Unless your nails grow at an alarming rate, you should be able to cover the moon just as easily whether it is high or low.

3. Best of all, if you want proof of how easy it is to skew your perception of size, bend over and look at the moon upside down through your legs. When we are faced with a new vantage point, all reference points and size comparisons are upset, and we realize how much we rely upon experience, rather than our sensory organs, to judge distances and size.

We do, however, suggest that this physically challenging and potentially embarrassing scientific procedure be done in wide-open spaces and with the supervision of a parent or guardian.
Imponderables
cannot be held responsible for the physical or emotional well-being of those in search of astronomical truths.

Submitted by Patrick Chambers, of Grandview, Missouri
.

204 / DAVID FELDMAN

If We See Mockingbirds During the Day and Hear
Them at Night, When Do They Sleep?

At night, but off and on, and with an occasional nap during the day.

Birds aren’t as compulsive as humans are about their sleep hours, but then they don’t have nine-to-five jobs. Birds also require much less sleep than humans, but then they don’t have taxes to worry about either.

Actually, it has proved to be quite a challenge to determine the sleep patterns of birds. Laboratory experiments can’t replicate the conditions they face in the elements, and any movement or sound the scientist makes during close observation will disrupt the sleep he is trying to measure.

No one has actually proved that sleep is physiologically necessary for birds. Its main benefit for them might be that standing still helps conserve energy: if a bird can’t hear a potential predator hovering or see a worm ripe for the picking, it can’t do anything about it.

While sleep leaves them more vulnerable to predators, it is all that keeps birds from an exhausting 24-hour-a-day hunt for food.

Simply standing motionless with their eyes closed or open provides rest for most birds. Birds that live in the Arctic or Antarctic regions and have to contend with periods of twenty-four—hour sunlight, often take short catnaps throughout the day and night, but require no long sessions of sleep.

For diurnal birds, like mockingbirds, the daytime is full of activity, but they don’t sleep peacefully throughout the dark hours, as anyone who has ever attempted to sleep near a male mockingbird knows all too well.

Submitted by Kathi Sawyer Young, of Encino, California
.

WHY DO CLOCKS RUN CLOCKWISE? / 205

Why Were Phillips Screws and Screwdrivers
Developed?

The straight-bladed screwdriver was popular long before the advent of the Phillips. Was the Phillips merely a marketing ploy to make old hardware obsolete?

Fred A. Curry, a retiree of Stanley Works and now an educational consultant, has a large collection of Stanley tools and old catalogs.

While trying to find an answer to our query, Mr. Curry found a 1938 article in Stanley’s
Tool Talks
, which, to use a hardware metaphor, bangs the nail on the head:

The most recent major improvement in screw design is the Phillips recessed head, self-centering screw and bolt. This type of screw is already extensively used in many of the major industries, and is even replacing the common wood screw for home repairs.

Stanley has the No. 1 license to manufacture the screwdrivers, hand and

206 / DAVID FELDMAN

power driven bits required by the Phillips screw, and now offers a complete line of these Stanley quality drivers and bits.

The main selling point of the Phillips was clearly the self-centering feature. Straight-bladed screwdrivers tended to slip out of the screws’

slots, ruining wood or other material, occasionally even injuring the worker. The recessed Phillips screws allowed a closer and tighter fit than the conventional slots. It may be harder, initially, to insert the Phillips screwdriver, but once it is in place, the Phillips is much less likely to slip.

Why Do Trucks Now Say Their Contents Are

“Flammable” When They Used to Say

“Inflammable”?

The prefix “in” usually means “not.” If you are
insensitive
, you are not sensitive. If you are
in
coherent, you are not coherent. If you are
in
flammable, you are not flammable.

Oops! You
are
flammable if you are inflammable.

The English language is less than a logical construct. “Flammable”

and “inflammable” have identical meanings: “easily set WHY DO CLOCKS RUN CLOCKWISE? / 207

on fire.” So why did the trucking industry bother to change its warning notices?

Fire-insurance underwriters are usually given credit for starting the changeovers. They felt that foreigners, unaware of this exception to the usual meaning of “in-,” might misconstrue “inflammable” signs, so they lobbied to change labels on containers and tanks to “flammable.” Scientists, always sensitive to the need for international understanding, have also adopted “flammable.”

Ironically, although the purpose of the change from “inflammable”

to “flammable” was to facilitate the understanding of nonnative speakers, almost all of the international agencies responsible for regulating the labeling of (in) flammable materials, such as the United Nations, have chosen “inflammable” as their standard. A. N. Glick, president of the Conference on the Safe Transportation of Hazardous Articles (COSTHA), told
Imponderables
that the International Maritime Dangerous Goods Code of the International Maritime Organization uses the term “inflammable” but permits the use of

“flammable” if there is a footnote reference.

The
Harper Dictionary of Contemporary Usage
had its panel of language experts (a group so concerned with preserving the English language that they still don’t quite trust Edwin Newman) vote on whether they used “flammable.” Most didn’t, but they couldn’t work up much enthusiasm for trying to fight its use, as it is less ambiguous to nonnatives.

I am surprised that nobody bothered to ask what an intelligent foreigner might think about a country in which companies bothered to put signs on their trucks announcing that the truck was carrying cargo that was
not
easily set on fire.

Submitted by Warrine Ahlgreen, of Tallmadge, Ohio. Thanks also
to: Allen Johnson, Ph.D., of Kennewick, Washington
.

208 / DAVID FELDMAN

Why Can’t They Make Newspapers That Don’t
Smudge?

Reading a newspaper might be good for the mind, but it ain’t great for the hands. After a bout with the Sunday paper, your hands are likely to look as if they have been engaged in a mud-wrestling contest rather than an intellectual endeavor.

What is that junk all over your hands? It is ink. And as much as these smudges annoy you, they bother the people within the newspaper industry even more. As Ralph E. Eary, who is responsible for the production and engineering of Scripps Howard’s newspapers, told
Imponderables
, “Ink rub-off has been my mortal enemy for forty years. I have experimented with various inks, dyes, and water-based inks over the past twenty-two years and each comes up a failure.”

Black news inks have changed little over the past forty WHY DO CLOCKS RUN CLOCKWISE? / 209

years. Inks consist of pigments, which produce colors, and “vehicles,”

liquids that carry the pigments. Conventional newspaper inks have an oil base. Oil never dries completely, which is why these inks smear on your hands and clothes. Black inks usually contain between 10 percent and 18 percent carbon black pigment content, with the balance consisting of mineral oil similar to automobile lubricating oil. Inks designed for letterpress machines have less pigment than ink used for offset presses.

Much hope was held out for the durability of water-based inks, but they have not proved to be a solution. In an article about ink for the journal of the American Newspaper Publishers Association,
Presstime
, technical writer Paul Kruglinski states the newspapers’

continuing dilemma: “Ink rub-off is a relative problem: Its cause and elimination are not dependent on any one variable. The incidence and amount of rub-off hinge on the ingredients in inks, the kinds of inks used in each printing process and the type of newsprint used.

It takes more than just changing chemicals to eliminate rub-off, researchers have learned.”

Two factors have exacerbated the rub-off problem in recent years.

The first is the changeover, by many newspapers, from letterpress to offset presses. In the letterpress process, the relief plate literally imprints the ink into the paper. The offset process works by what is called a “kiss” or “touch” impression, in which ink is deposited on the surface of the page, where it is more likely to smear.

The second and perhaps more significant trend over the past few decades has been toward publishers using heavier ink (adding extra pigment and oil to a particular area of page space) to make the paper more easily readable. The
New York Times
, for example, is extremely dark; the
Wall Street Journal
is printed with much lighter ink. Unfortunately, the
Times
and other newspapers pay a price for their high contrast—higher rub-off and higher “show-through” (the tendency of the print on the back side of a page to be visible on the front).