Most of the time, when a police officer asks a merchant for a favor, the merchant falls all over himself to comply. After all, if there's ever an emergency on the premises, Mr. Merchant wants Mr. Cop to respond as quickly as possible.

But what if the favor consists of a cop's asking for a little shelter from the rain? No free food. No free drink. No free service. Just a dry place to fix a flat. Would a merchant ever be justified in saying no? Would a merchant ever find a reason to say no?

Alas, a gas station owner in Northwest Washington refused to allow two D.C. police officers to change a tire in an empty, indoor bay one day in August.

It was raining cats and dogs at the time. The cops had a flat on their cruiser. They asked the owner if they could use the service bay to change the flat themselves.

According to the wife of one of the officers, who wrote to me, the owner said:

"Sure, for $10."

The officers pointed out that they weren't asking the man to change the flat for them. They simply wanted a dry place to do their own dirty work. Besides, the service bay wasn't being used.

The owner's response: "Well, you don't work for free, do you?" The officers ended up changing the flat outdoors, and getting soaked to the bone for their trouble.

My correspondent, Marianna C. Spicer-Brooks, of Lorton, was infuriated by the incident. "My husband has nearly lost his life on numerous occasions protecting or saving the lives of people in this city," she writes. "I find it hard to believe that this service (and I use the word loosely) station owner could not find it in his heart to help out two officers who were asking very little."

I called the service station owner on several occasions over several days in search of his side of the story. I left a message each time. The owner never called back. So, in keeping with my usual policy, I won't name the station or give its address, since it has not offered a defense.

If the owner sees this column, and decides to come forward, I'll publish the name of the station at that time. Otherwise, I believe it's fairest to keep that information anonymous. I don't want to destroy this man's livelihood. I only want him to think about what he did -- and do it differently next time.

In any case, Marianna Spicer-Brooks is about as right as right can be. The service station owner should have offered the empty bay to the two cops, not because they were cops, but because they were human beings.

To Marianna's husband, Michael Brooks, and his partner, my hopes that you guys have dried off by now. To Marianna, my thanks for writing. To the service station owner, my disappointment.

It takes a big man to call himself an idiot. It takes an equally big man to apologize. The "idiot in the brown Buick Century" called me last Wednesday to do both.

"I was driving south on Ninth Street NW, near the gallery, on Aug. 30 at about 7 p.m.," my contrite caller began. "I was in a big hurry, and I cut off a bus. Just cut him off. Zipped right in front of him. He had to hit the brakes, hard.

"I made a mistake. I just feel bad about it. It's been bothering me, and I just had to let the driver know how I felt. You know, Bob, because you write about them a lot, but bus drivers do work hard. I hate it that I added to one driver's troubles.

"Would you please say in your column that the idiot in the Buick who cut you off is really sorry?"

Just did it, my friend. Would that all idiots were as eager to make amends as you.

You thought vacations were a blessing? Brian Miller learned recently that they're anything but.

Brian received a sales-pitch letter from a Fairfax communications company that was offering "advanced service" for phone systems.

And what is advanced service? "Provides basic service plus 24-hour service for any catastrophic problems, including holidays," the letter said.

Thanks to Shelley Mullins, of North Potomac, for passing along word of a breakfast I may be glad I missed.

It was held at the Montgomery County Fair last month. According to a schedule published in one of the county papers, the feed was "free to the fair's first 1,500 paying customers, courtesy of Maalox."

And thanks to Syd Kasper, of Silver Spring, for passing along the message he saw on a sign outside a gas station under reconstruction in Truro, Nova Scotia.