It's a scene that's played out hourly. A niece from (in this case) Pittsburgh comes to visit her uncle in Washington. He meets her at the Greyhound Bus Terminal, and they walk out front onto New York Avenue to get a taxi.

This, too, is a scene that's played out hourly: a ferocious battle among cabbies in line at the Greyhound station to avoid short runs and small (or nonexistent) tips.

The uncle who walked into ferocity with a capital F is Larry Gaffney. When he and his niece emerged from the bus station, three cabs were waiting in line. The first two had luggage in them; presumably, passengers had deposited some of their belongings and gone back into the terminal to get the rest.

So Larry and his niece approached the third cab and asked to go to Union Station. Larry stated the destination loud enough for the other two drivers to hear him.

Union Station is about four minutes' drive from the Greyhound station. Fare plus tip for two passengers averages $3. If you're a hacker, that's not the way to become independently wealthy.

So the third cabbie loudly ordered Larry and his niece to take the first cab in line. Larry pointed out that it was occupied, by baggage, if not by human cargo. The cabbie repeated his order. Upset by now, Larry began writing down the license numbers of all three cabs. Whereupon one of the drivers screamed a racial epithet at him and all three cabs refused to take either him or his niece.

Larry's niece had been to Washington as an adult only once before. For years, her uncle had sung the praises of living here. In fact, she had come to Washington to interview for a job here. "That was one helluva rude welcome," said Larry.

Technically, said Tom Martin of the D.C. Department of Transportation, the third cabbie was correct. "General policy is that the first cab in a line must take a passenger," Tom said. But if there are extenuating circumstances, Tom added, the "first available cab" in a line must take a passenger.

I'd call luggage inside Cab One and Cab Two pretty extenuating circumstances. Cab Three was obviously looking for a $30 run to Fort Belvoir, not a $3 spin to Union Station. That's understandable, but it's also illegal.

Preventable, too. How long before a dispatcher with real authority is assigned to the Greyhound station? He would keep uncles from losing their cool. Cabbies, too.

Mary Kelly of Chevy Chase got a letter recently. "It was a note of thanks for a wedding present from a party whose name was unfamiliar at first reading," Mary writes. "So I set it aside to discuss with my children, whose friends' married names I'm not accustomed to committing to memory."

But none of the kids recognized the thanker, either. So Mary took a closer look. "I discovered, with considerable shock, that the postmark was Clayton, Missouri, January 10, 1966, mailed with a five-cent, 1965 Christmas stamp."

So now you know why it costs 22 cents to mail a letter in 1985.

Five cents gets a letter to its destination in 19 years.

Twenty-two gets it there sooner. How much sooner? Knowing the postal service, that's anybody's guess.

Idea Whose Time Has Come, from Michael R. Warren of Northwest:

Recently, Mike was passed at a high rate of speed by a car containing a Ma, a Pa and several kids. Mike notes that if that car were involved in an accident, many more lives would be at risk than if the car had been occupied by a mere driver.

"Seems to me that the fine for speeding ought to be multiplied by the number of people in the car," Mike suggests. "And, since it sets a bad example for children, unlicensed minors should count as two people."

Excellent! Do you have a notion that would do as much to preserve civilization as we know it? If so, mail it to Bob Levey, The Washington Post, Washington, D.C. 20071.

Neatness counts. Brevity counts even more.

What was that, Levey? You're taking another vacation?

'Fraid so.

How long this time?

Another two weeks. I know how tough it'll be. But take lots of cold showers and breathe deeply for five minutes a day. You'll get over it.

How come you rate another vacation so soon?

Just lucky, I guess.

Come off it.

Well, I have all this leave saved up, and it's burning a hole in my pocket.

But you'll be back on April 8?

Count on it. See you then.