Let's sing about an unsung hero this morning. His name is Larry Young, and his bosses say he's a genuinely aw-shucks kind of guy. He shouldn't be after what he did the other day.

Larry is a tour guide for Old Town Trolley Tours. One Friday morning, he made his scheduled stop at the Hyatt Regency Hotel near Capitol Hill. One of the passengers he picked up was Pat Sturm of Weatherford, Okla.

"The tour proceeded, with Larry bantering all the way about the sights, history and gossip associated with each point of interest," Pat writes.

After picking up more passengers at the Sheraton Washington Hotel, Larry was waiting for a red light to change when he noticed that a school bus parked across Cleveland Avenue was smoking. Not only that, but the bus was full of kids.

"Without a second's hesitation, Larry hopped out of our trolley, crossed four lanes of traffic and alerted the school bus driver," Pat writes.

" . . . .The driver tried to quench the fire with an extinguisher, but did nothing about the children on the bus. Larry reentered the bus and began the process of evacuating the children. Once the children were on their way to safety, Larry came back to our trolley, wheeled onto Cleveland Avenue and continued our tour as if nothing unusual had happened."

It was Classic Larry.

"Larry is sort of a quiet guy and doesn't talk about himself very much," said Rob Mawson, general manager of the company.

Chris Delland, the owner, added that he gets a letter every week from a tourist who enjoyed one of Larry's narratives.

Rob said the Old Town brass is still debating how to congratulate Larry for his quick thinking and quick feet.

I think we just took care of that, fellas.

All right, you daily Beltway sufferers. This doesn't come with a money-back guarantee, but it may be a ray of hope.

A reader says he has commuted to work on the Beltway for 20 years -- from four different homes to four different jobs. The various combinations have brought him face to face with all 60-plus miles of The Big Round Noose, during both rush hours. So he knows whereof he speaks.

This reader claims that the best time to be on the Beltway during rush hour is at 15 minutes after the hour or half hour in the morning, and 15 minutes before the hour or half hour in the evening.

Why? "Because almost every shift at every office begins and ends on either the hour or the half hour," my reader says. "And even if an office has flexitime, people are mentally conditioned to arrive or leave on the hour or on the half hour. That means the worst time to be on the Beltway is at 15 minutes before the hour or the half hour in the morning, and at 15 minutes after the hour or half hour in the evening."

My reader calls this the Wave Theory.

I can see holes in it the size of a tractor-trailer.

First of all, 15 minutes after an hour or a half hour is also 15 minutes before another. So if my reader's theory works at all, it probably works only toward the end of rush hour.

Second of all, Beltway traffic often clogs without warning and for no obvious reason. Let's say thousands of motorists might have produced a clog at 8:45 a.m. But on a particular day, if there's an unexpected delay, the same motorists will produce the same clog at 9:15.

Third of all, if my reader is correct, the word would have gotten out by now, and zillions of motorists would have altered their commuting schedules to take advantage. In no time flat, that advantage would cease to exist.

I checked with traffic officials in D.C., Maryland and Virginia. They say they've never heard of the Wave Theory. Nor do they place any stock in it.

But I've run the theory past a few dozen Beltway regulars over the last few weeks. They say they've not only heard of it, but it works -- especially on Tuesdays, Wednesdays and Thursdays.

If you shoot for the 8:15 "wave" tomorrow morning, and you end up in the most horrendous backup ever known to mankind, don't come looking for a piece of my hide. But if you get to work five minutes faster, you'll know why.

Thanks, Bonnie Balick of Gaithersburg, for another in our collection of absurd highway signs.

Bonnie "turns in" a sign she spotted in Middleburg, Va.

It reads: "ROAD ENDS, 0.02 MILES."

As Bonnie points out, 0.02 miles is a little more than 105 feet. By the time you get to within 105 feet of the end of a road, you'll be able to see that it's ending without a sign telling you so.

Julius Adamson says that diamonds used to be forever. Now forever is the Iran contra hearings.