Only the vain or foolish will ask a mirror, or some other dangerous implement, who's the fairest of them all. The question at hand is why so many southern women ask that question, and why they hear the desired answer so often.

Southern magazine placed this intriguing matter in novelist Beverly Lowry's capable hands. Her September cover story works from the confounding statistic that eight of the 10 semifinalists in last year's Miss America pageant were from the South.

"They're professionals," observes a northern contestant. That may be -- the 1986 Miss America, Mississippian Susan Akin, was a veteran of 50 contests before she won the big one. And the South has more beauty pageants. "Agriculture is probably one reason," Lowry writes of the fruit bowl of festivals southern women vie to be queen of -- "the ancient tradition of celebrating the harvest through ritual ceremony."

Mary Francis Flood makes a living as a beauty contestant's adviser. Along with basic physical upgrading and tips on making teeth shine with coatings of Vaseline, Flood sees to instruction in how to make eye contact and say things like, "Yes I have, Bob," and "That's right, Bob." Flood's theory on southern dominance, about Mississippi's entries specifically, is this: "Our girls have a beautiful gait." (Desirable walking, incidentally, varies with the pageant. "USA," Flood says, using the insider shorthand, "likes a looser walk than America.")

One pageant executive explains things in that's-that mode. "The South honors womanhood. The South is proud of its girls. And it is proud of their culture." (A year's worth of Southern, at $12.95, is available by writing P.O. Box 3418, Little Rock, Ark. 72203-9990.)

The Sky Is Falling Powerful syndicates must have intimidated U.S. news organizations into keeping a lid on this story. It appears, as first published in the Independent of London, in the September issue of World Press Review, the newly redesigned monthly compilation of news and commentary from overseas.

According to Nigel Henbest, "in the past 2,000 years, the sun's apparent position in the sky has slipped backward by one whole sign of the zodiac." Meanwhile, when a research team sought to correlate 50,000 character traits with the actual personalities of 16,000 famous people grouped by astrological sign, it found -- no correlation.

Henbest's conclusion cannot be gainsaid: "Astrologers have stuck with tradition, even though it is now out of step with reality." This means every Pisces is an Aquarius, every Aries a Pisces, and so forth (backward), and also that millions of opening exchanges between men and women in singles bars were meaningless after all.

Dispatches We scarcely need reminders that life isn't as exciting as it used to be, or that ordinary people can't express themselves as well as they used to, but here's another: the Spanish Civil War letters of Margaret Palmer, an American expatriate and overseas agent for the Carnegie Institute's Museum of Art.

These dispatches -- to the museum director in Pittsburgh, evidently a mentor -- recount Palmer's stirring efforts to rescue the icons of Spanish art from the bruising proximity of battle -- including the perils she encountered leading truckloads of Goyas to safety in the dead of night.

In Palmer's Madrid, with the trenches only a 30-minute walk away and the city pockmarked by artillery fire, the pace of cultural activity and intellectual palaver does not let up. Eventually, though, she decamps to Paris and Vienna, where her dispatches continue to reflect a perceptive artistic eye and a persistent belief in the rightness of the Republican cause.

"Letters from Spain: 1936-1939" appears in the new issue of Archives of American Art Journal (look for the Picasso horse's head on the cover). The magazine, a member of the extended Smithsonian Institution family of publications, carried the letters of Palmer's Carnegie counterpart, Charlotte Weidler, last year.

Table of Contents "Strange things are happening in Iowa," writes Joe Klein, the new political columnist for New York, in its Sept. 7 issue. "Jesse Jackson has been making waves across the state, drawing crowds that are larger and more enthusiastic than any other candidate's, and tapping into a classic midwestern populist vein -- attacking the bankers and the big corporations ..." According to Klein, Jackson's people predict he'll get 15 percent in the Iowa Democratic caucuses next February, squelching the "black candidate" issue in an almost all-white state, and reach the convention with enough delegates to broker it. Acknowledging the heavy baggage Jackson carries, Klein still sounds like a believer.

The appearance of Architectural Digest's new offspring, Architecture, proves that the mother magazine has had the wrong name all along. Judging by the September premiere issue, the new publication looks like a serious effort at architectural discussion for the sophisticated but untutored reader. Floor plans supplement photographs of luxury, and architects are heard to comment on why they have wrought what they have wrought.