Oh, those sludgy squdgy valves.

Shell says in its recent batch of television commercials, that the petroleum titan is adding nitrogen to its gasoline to clean gunk off of valves and other moving parts.

Those who understand how an automobile engine works should immediately recognize the colossal blunder in the ad.

Meanwhile, the atmosphere is already almost 80 percent nitrogen by volume, so there's already loads of the inert gas entering the cylinder. After the gasoline burns, the catalytic converter quickly breaks the nitrogen oxides created at high temperatures, into nitrogen gas and water.

So, what is it Shell is adding? Nitrogen is present in protein, and countless other compounds. But it is most often associated with explosives, (the nitro in nitroglycerin), ammonia, hydrazine rocket fuel, ammonium nitrate, and all sorts of nasty stuff. Of course, so is oxygen, carbon, and every other element, other than xenon, helium, and stuff like that.

Did you figure out the blockhead mistake in the ad yet? The ad shows gasoline showering down on a cylinder valve, cleaning away accumulated sludge. That would mean gasoline in the rocker panels and on the cam shafts. Gasoline never gets into cam shaft territory and certainly does not stream onto the tops of cylinder valves.

The only gasoline that hits the top of a valve would be a gas-air mixture, vapor really, from an ancient device called a carburetor, which cars don't use these days.

That makes the add doubly mysterious. Companies put all sorts of compounds into gasoline to maintain the engine, such as nitrogen-containing detergents, petroleum distillates, and who knows what else. But nitrogen?

And someone should have pointed out that if gasoline reaches the external tops of the valves, something is seriously wrong with the engine, like it's in the middle of a horrendous crash and is disintegrating.

To clean the tops of the valves, put some cleaning goop in the oil. Gasoline goes into the cylinders via the valves, and the valves are lubricated and cleaned, or not, by oil that circulates through the engine.

T0 clean the underside of the valves, where the high temperature gas-burning takes place, add something to the gasoline.

Don't expect that nitrogen-laced gasoline is going to make your engine last 500,000 miles.

Mommy, can I please get this toy bull pup assault rifle?

Why are children, especially boys, drawn to guns?

Many parents avoid buying toy guns, do not expose their babies to violent TV shows or games, and yet, the youngsters want squirt guns, Nerf guns, or will fashion substitutes.

More than one baby has bitten a piece of toast into the shape of a pistol, horrifying and puzzling his parents.

While babies seem to be born with an innate fear of heights, darkness, snakes, and a few other things, gun lust is unlikely to be genetic. Aggression may be in our genes, but not the preference for a particular weapon.

Children must acquire a knowledge of guns from their environment. Television shows have greatly reduced explicit gun violence. Twenty or thirty years ago the Lone Ranger, Eliot Ness, Ben Cartwright and other characters routinely shot and killed people. The victims, not displaying any injury or blood, instantly dropped dead.

How does a child shielded from CSI, Grand Theft Auto, Metal Gear Solid, Mortal Kombat, and restricted to family-friendly Disney movies, learn about guns?

Possibly because of what's happening in the world.

Most children won't go near a newspaper, but the wars in Iraq and Afghanistan leak in through discussion, and television news. Columbine and other notorious school shootings are over-covered by 24-hour news channels, and are apt to be overheard.

Perhaps the knowledge comes through their friends: "I'll be Osama bin Laden and you be the 10th Mountain Division. I'll take the AK-47 and you get the M-16."

Maybe a gun, even a toy one, gives children a feeling of safety in a post 9/11 world with a scary former vice-president predicting Armageddon, flag-draped coffins being unloaded from Air Force cargo planes, neighbors being shot, and stray rounds crashing through bedroom walls.

Can you really blame a kid for wanting to protect him or herself, even symbolically?

People, pellets and public health

Almost everyone is mixed up about air guns.

Let's briefly put aside the issue of taking an air gun to school and shooting a fellow student.

That obviously is wrong and requires disciplinary action. The 9-year-old Celentano School student who shot an airsoft gun at a another boy on a bus probably now appreciates that carrying a weapon of any sort, even something as innocuous as an airsoft gun, poses more risk than safety.

"Air gun" encompasses many different types of weapons, ranging from toys to rifles capable of killing small game.

Airsoft guns were introduced in Japan in the 1980s for teens fascinated with real guns, which are illegal and difficult to find there. Participants played a "combat" game like paintball with these plastic guns, which were considered toys.

Air soft guns employ bright orange barrels to indicate that they only fire plastic pellets, but it is a simple matter to paint the barrel or cut it off.

They were considered toys because they fire small (6 mm) plastic pellets at a slow velocity. Since kinetic energy equals the mass of the pellet times the velocity multiplied by itself, and all of that divided by two, it is clear that the only way to seriously injure someone with an airsoft gun is to use it like a club.

The one exception is that eyes are delicate and unprotected, so goggles had to be worn, along with plastic "armor."

Then there is the BB gun. BB guns were devised to fire BB-sized bird shot. Most BBs are made of steel or copper. The .177 caliber spheres can travel at 300 to 400 feet a second, and could conceivably cause serious injury. These are not toys.

The next step up the air gun line is air rifles. Some use a built-in pump to compress air. More powerful air guns compress air using a large, powerful spring. The highest quality air rifles are made in Germany and cost more than conventional firearms.

Spring loaded air rifles can fire a .177-cal. pellet at up to about 1,000 feet a second. The speed of sound is about 1,100 feet a second, and supersonic pellets make a loud "crack," which is self-defeating. Europeans (mostly) use these weapons to eliminate rats, and keep rabbits, starlings and other unwelcome small animals away from farm lands.

The most powerful air rifles propel .22-cal pellets at 800 to 900 feet per second.

Many of these rifles are used for target shooting in lieu of conventional rifles, because air rifles are the same size, but are relatively quiet, use inexpensive ammunition, and do not require a permit.

All air rifles should be treated as "real" guns, should be equipped with trigger locks, locked in a cabinet, and pellets should be locked in another container. As with firearms, you always act as if the rifle is cocked and loaded, never point it at anything you do not intend to shoot, and consider what is behind the target, because it is in the line of fire.

Hardly any robber uses an air rifle because the arms are large (45 inches long), heavy and unwieldy. Moreover, a conventional pistol has a higher muzzle velocity and much heavier projectiles, and can readily inflict lethal wounds.

Consequently, many criminals use use real-looking airsoft guns, or pellet-firing pistols to commit crimes. Perhaps they think that using an air weapon will aide their legal defense when caught, but it doesn't.

But air soft gunfs are cheap and easy to acquire and are sufficiently gun-like to scare potential victims. The least we can do is make realistic toy guns illegal.

If kids want to play games -- and they seem to be genetically programmed to fight mock battles -- they can use Nerf guns that are fancifully shaped and shoot light foam cylinders at low velocity. No one could confuse a Nerf gun with the real thing.

Ultimately, here's what needs to happen: toy manufacturers must stop producing realistic-looking weapons; air rifle ownership should be regulated, and only people with a demonstrable need should be allowed to own real firearms.

Unfortunately the Second Amendment is ambiguous and grammatically obscure, so gun fanciers and the firearms lobby will continue to ensure that gun ownership if widespread.

The question is, would the National Rifle Association consider a ban on air soft guns to be an assault on our Constitutional rights?

How about a bit of common sense

There are a lot of reasons that people in other countries are not cozy with the United States.

Here is one minor example of why.

The problem here is drill bits, or rather, describing the diameter of drill bits. The rest of the world uses the metric system, which is simpler than whatever it is that we're using.

Here's the assortment of bits: 1/16th of an inch; 5/64ths; 3/32nds; 7/64ths; 5/32nds; and 3/16ths. Using this method requires thinking about common denominators, admittedly not a tough mathematical problem, for the most part.

Seven 64ths of an inch is one 64th from being 1/8th of an inch. Three 32nds is one 32nd from 4/32s, or 1/4th of an inch. What's the difference between 5/32nds and 3/16ths? One 32nd of an inch. Why not make all of the bits in 32nds? Too simple.

In the metric system, the same set is 1.59 millimeters; 2 millimeters, 2.38 mm; 2.8 mm; 3.18 mm, 3.97 mm and 4.8 mm. There are 25.4 mms in 1 inch. So 2.38 mm is a little less than 1/10th of an inch, which we call 3/32 of an inch. Which is a little less than 1/10th of an inch.

Can't we at least use 10ths of inches? Instead of using odd little increments like 5/32s?

Or, you can ignore the whole thing and just eyeball which bit you want. Then a few weeks later your shelves fall off the wall.

Phone home if you dare

Chances are that once in a while your cell phone cannot project its tiny radio signal to the nearest relay tower.

So, it's not like you're holding a 50,000-watt transmitter against your head. You're holding a thing the size of a pack of gum.

Yet researchers in Australia have concluded that using a cell phone (against the ear) for 10 years doubles the risk of brain cancer (for you, not them). Aside from the fact that dozens of studies of the same hypothesis have found absolutely no link, 60 Minutes, the Australian version, apparently, decided that a man with brain cancer must have developed it because he used a cell phone.

This guy is a farmer. Who was he talking to? Anyway, the report, by a hyperventilating Aussie, would be enough to make you throw away your LG unless you think about it for a fraction of a second.

First off, we are constantly bombarded through and through with FM, AM, shortwave, emergency band, and other sources of radio waves. If you could see radio waves, your room's walls would be glowing furiously. Not to mention television, computers, and everything else that creates electromagnetic radiation.

Remember: 20 years before cell phones there were cordless phones. Now almost everyone has a cordless phone, even though it seems to old fashioned. Cordless phones work by -- you guessed it -- radio waves, from your phone to your base station.

So we should have seen the doubling of brain cancer by now. And yet we haven't. Just to get to the heart of this, some electromagnetic radiation is sufficiently energetic that it can knock apart atoms and molecules. This is called ionizing radiation, x-rays for example, and they are not good for you.

Radio waves, on the other hand, have far longer wavelengths, and consequently, they are way less powerful. Radio waves do not ionize. Microwave ovens do not ionize. Gamma rays ionize. Cells phones, no.

This business with cell phones is worse than Paul Brodeur and his fantasy about carcinogenic electromagnetic fields around power cables. There may actually be something to that. Probably not, and if there is, it is so rare that it is impossible to pick out from the epidemiological noise.

The opposite of, say, working in a coal mine and developing black lung disease.

Just to be on the safe side, hold the cell phone at arm's length and yell into it. Especially while on public transportation.

A billion is way bigger than a million.

Okay. Here's a little math for people who are livid about $165 million in "bonuses" to employees of the corporate carcass once known as American International Group.

AIG received $30 billion from the Federal Reserve to somehow rid itself of insane insurance policies on a sliced and diced mixture of below-prime-rate mortgages. Or, what we now call "toxic assets."

How galling is it for a Greenwich millionaire cum-crook to get a million or two or three dollars for sabotaging the company while becoming filthy rich, causing untold misery to everyone else?

Pretty high on the Gall Scale. Right up there near the top.

But people want the money back as recompense for the $30 billion. Let's consider the numbers 165 million and 30 billion.

One million is 1 followed by 6 zeroes One billion is 1 followed by 9 zeroes. Three additional zeroes, or you might say, three orders of magnitude. Now, think about it.

Since Earth's population is about 6 billion, then 30 billion would be the number of people on five Earths. By contrast, 165 million is about the populations of the 10 largest cities on Earth.

Or, to put it another way, 1 million seconds is 13 days. One billion seconds is 31 years. A million hours ago it was 1855. A billion hours ago humans did not exist.

One more. There are about 10,000 grains of rice in a cup. Sixteen cups equals 1 gallon of rice. So, 1 million grains of rice would be 6.5 gallons. One billion grains of rice would be 6,500 gallons.

Consequently, $165 million is about half of one percent of $30 billion. It's chump change.

Of course, $165 million would make us chumps pretty rich -- but paupers compared to a Bill Gates or a Warren Buffet.

By the way, 1 trillion seconds ago Neanderthals were hunting mammoths and trying to stay warm.

Earmarks for dummies

Many trivial-sounding "earmarks" are criticized as a waste of money, usually by people who don't understand the value of basic research.

Earmarks have faded from the news, pushed into the background by enormous bail-outs that are orders of magnitude larger than the supposed pet projects in the proposed federal budget.

Here are a few projects revealed earlier this month by New York Time columnist Maureen Dowd:

+$2.1 million for the Center for Grape Genetics in New York. There's nothing funny about this to the growing U.S. wine industry. There are roughly 600 varieties of grapes, 54 of which comprise the main ingredients in most wines around the world.

Genetics are very important to wine.

Phyllorexa, a plant louse that loves grape leaves, appeared in the 18th century, first in America and then in Europe. Ultimately, after some back and forth, America began to provide phyllorexa-proof roots to Europeans, who graft on local grape varieties.

The point is, resistance to rot, insects, fungus, nematodes, etc. lies in genes, and the more we understand about grape genes, the safer the wine industry. California's wine industry alone is worth about $20 billion a year. So $2 million to assure its safety seems like a n0-brainer.

+ $1.7 million for a honey bee factory in Texas. Bees are essential to pollinating many crops, and bees are mysteriously disappearing. If the factory helps figure out what's going on the money will be well-spent.

+ $1.7 million for pig odor research in Iowa. Big joke, except that pig poop could be a source of biofuel, either by collecting the methane it gives off as it rots, or through some other biomass process. Do you want to live next to a pig fuel plant? No, because of the odor. So this grant has a serious purpose.

+ $2 million to develop and promote astronomy in Hawaii. Part of the reason that astronomy is conducted in Hawaii is because the mainland is wasting prodigious amounts of light, lighting up the night sky and obscuring stars, galaxies, and possibly even some planets. The skies over Kitt Peak (near Tuscon, Arizona) are way clearer than the skies over the East Coast. But Arizona cities are spreading like phyllorexa.

What's important about astronomy? Are you curious about the origin and future of the universe and the solar system; life on other planets; or the possibility of colonizing Mars or predicting asteroid collisons? That's astronomy.

There's more, but you get the idea.

A couple of centuries ago, how ridiculous it would have seemed to study why apples fall to the ground. That story about Isaac Newton may be apoccryphal, but you never know where a simple question will lead.