DEAR BEVERLY,

Too bad about your February blues, but you won't get rid of them by visiting me. It's the doldrums in Washington too. Even Popsie Tribble is going through a mini-depression because all her enfriends were asked to go cruising down the Nile on a Famous Name's yacht and somehow she was left off the guest list. To compensate she's boning up on arms control, which is the "in" topic of conversation in Powertown.

Popsie attended a B-list party at Baron Spitte's ("He's getting old," she says, "and doesn't care") where she met a Professor Otto Wither from Georgetown University who offered to give her arms control lessons in her home, for a fee. (He brings his own color slides and published articles.) Mr. Ambassador told me to join Popsie and be instructed because "wife of" knows only last year's topics -- the election, which no one wants to hear about now, and the deleterious effect of Canadian pork imports on Nebraska's economy, which I never wanted to talk about even last year.

Before Popsie started her arms control lessons, she rang me up to tell me what a slump she was in.

"Do you know what I did this morning?" she said gloomily. "I'll give you a check list:

"1.I wrote one thank-you note to the wife of Senator Pod who gave a hunger luncheon (day-old bread, processed cheese slices and Washington water) to remember the starving. It cost me $50 and I didn't have a good time at all.

"2.I put artificial tanning lotion on my face so now I look yellow instead of white.

"3.Thought about having a pedicure, but who's going to see my feet in the next three months?

"4.Made six phone calls to people who I know are here. Nobody answered except the maids. Everyone but me must be doing something interesting.

"5.I tried to read an article about arms control in The New York Review of Books but put it down and picked up the TV Guide instead."

You notice, Beverly, it didn't sound like our old self- confident Popsie. But I think she started to perk up when Otto Wither began telling us about Mutually Assured Destruction and the Balance of Terror.

It was during our second lesson that Popsie had her idea.

"I'm going to give an Arms Control dinner, black-tie. Do you think I should make Merv the guest of honour," she asked the professor, "or will the other arms negotiators become jealous?"

Wither had dropped the name Merv amidst all those initials like GLCM, SLBM, INF, ASAT and ICBM.

"Merv," Wither explained a bit acidly, "is not an arms-control negotiator. Merv is not even a person. Merv means MIRV, which is a multiple independently targeted re-entry vehicle."

I'm sorry to say, Beverly, both Popsie and I looked blank.

"Perhaps I'm going too fast for you ladies," Wither said. "It's a missile, like all those other initials. But it can hold 10 atomic bombs, which can be fired separately, in different directions."

Popsie's always been very competitive, so I wasn't surprised when she asked, "Who has the most MIRVs?"

"The Russians," Wither said.

Popsie looked unhappy.

"Does that mean I have to leave Ambassador Dobrynin off my invitation list?"

"Not necessarily," "wife of" piped up, "the Americans have more SLBMs." I hoped that Wither would notice that I was smarter than Popsie.

But Popsie knew more than I guessed.

"Ice Station Zebra," Popsie said thoughtfully. "Rock Hudson was the captain of the nuclear submarine. Howard Hughes watched it over and over before he died."

Popsie suddenly had that smug look on her face which she gets when she knows she's going to conduct a social coup in Powertown.

"If I invited Kampelman, Glickman, Sen. Tower and Dobrynin to my dinner, that would create a strategic balance."

"Precisely," Wither agreed, "Think of Dobrynin as a MIRV and the American negotiators as SLBMs. You would definitely maintain the Balance of Terror at your party. Although," he said, "the Russians might insist that you invite Karpov as well." "What's a KARPOV? I asked.

"Karpov is not a missile," Wither patiently explained. "He's a Soviet negotiator. Mrs. Tribble's dinner is certainly a social metaphor for Mutually Assured Destruction," Wither said happily.

Popsie was troubled. "I don't think I want that," she said.

"You don't understand," Wither explained. "Some experts believe Mutually Assured Destruction is a good thing. If the Russians MIRV us, we SLBM them. Both sides know that. So nobody does anything. It just means your party will not be destabilizing."

"Sounds dull, like one of Baron Spitte's dinners," Popsie mused. "Maybe I should have a Star Wars party."

"You mean you are going to ask an SDI for dinner?" I said, hoping I was using correct terminology.

"It would be worth destroying the Balance of Terror," Popsie said, "if everyone in town knew I had the President for dinner."

Your best friend,

-- Sondra