WITH ADMIRATION, disapproval, pride and disappointment Americans take great interest in the personal style of the reigning first lady. From the French fashion designers Jacqueline Kennedy favored as first lady to the gifts Nancy Reagan accepted from American designers, the clothing issue has entangled many. Pat Nixon was accused of not having enough style. One reporter wrote of her in 1969, "If only Pat would do something for the hell of it." When Rosalynn Carter brought her sewing machine to the White House, it was interpreted as a slap in the face of Seventh Avenue.

Certain pieces of clothing will always remain in the memories of Americans: Jacqueline Kennedy's pink suit stained with the blood of her slain husband; Lady Bird's bright yellow sensible clothes; Pat Nixon's Republican cloth coat; Betty Ford's scarves; Rosalynn Carter's not-brand-new gown; Nancy Reagan's $25,000 inaugural wardrobe.

The Magazine's Anne Behrens talked with Margaret Brown Klapthor, the curator emeritus in the division of political history of the National Museum of American History of the Smithsonian Institution, where Klapthor has worked for over 40 years. Klapthor's specialty is the collection of the first ladies. Here are some of her recollections. Power of the Pillbox

JACQUELINE KENNEDY, who very much liked French fashion, tried to downplay that fact, so that people didn't know when she was wearing a French-made gown. She always wished to spotlight the fact that she was actually wearing American clothes made by as many American fashion designers.

She liked Oleg Cassini, and he did a number of dresses for her. But her inaugural ball gown was from a sketch that Jacqueline made herself; it was made by Ethel Franco who was head of the designer fashion salon at Bergdorf Goodman in New York City. She knew exactly how she wanted it to look.

She suggested they use a very handsome silk as the basic foundation of the dress, and then cover it over with a number of layers of silk chiffon -- each one going in a different direction -- giving it a very deep matte finish. Then the bodice of the dress, which is beautifully embroidered with silver, was even veiled over with the silk chiffon.

That night, when the lights hit the chiffon, you could just see a little glint once in a while of the silver and silk underneath so it did create the kind of effect she was trying to achieve -- something that was very elegant looking, very deep, very rich looking.

She didn't like her clothes to be the main thing that she was noted for as first lady, though. She was very careful to publicize the more cultural things she was interested in, like the ballet, music, the interior restoration at the White House and so forth. She felt those kinds of things were more substantive. But like it or not, people were very much interested in what she wore and young women all over the country adopted the kind of styles that she wore. The little pillbox hats that she wore to the first inauguration were immediately worn by people all over the country, and her styles -- the kind of clothes that she wore -- definitely influenced what Americans were wearing.

Jacqueline had an innate sense of fashion. And I think she really did like to look well. She downplayed it because it was being made a rather nasty political issue during the campaign. She really got mad at the publicity about how much she spent on her clothes. That was when she said, "I couldn't spend that much if I wore mink-lined underwear."

She dressed to please herself. She was proud of how she looked as a representative of the American people. REPRESENTATIVE WOMAN

LADY BIRD JOHNSON came from the Southwest, where fashion was not as important as it was to somebody who lived in the northeast corridor, where clothes were available and where how to dress was something that a woman knew almost instinctively from the day she was born. That was something Mrs. Johnson had to learn.

But she did learn it. You can see the increasing sophistication in Mrs. Johnson's clothing during the time that she was in office.

Lyndon Johnson liked for his women to look well, to be pretty. He was insistent that they shouldn't gain weight, they should have and maintain nice figures. So Mrs. Johnson was definitely dressing to please him as well as to please herself and to please the American people.

I don't think clothing or fashion per se was one of the strong interests in her life. I think she was much more interested in things like her beautification program and Johnson's programs for the Great Society.

Mrs. Kennedy seemed to be dressing for the people who were interested in high style and Mrs. Johnson saw herself as representing women from al over the country. Mrs. Johnson's clothing was chosen to be the kind of thing that more people were able to wear, people in her own age group.

That beautiful silk fabric that Mrs. Johnson's inaugural gown is made of -- that really heavy, heavy, heavy yellow satin -- was probably something that the designer was fascinated with. And Lady Bird likes bright, cheery sunshiny kinds of things, so it probably was a meeting of the minds. She looked pretty in it with her dark hair.

Mrs. Johnson's dress is perfectly plain; there is no ornamentation -- it just has a beautiful line. The coat has the only decorative note on it, which were the fur cuffs on the sleeves.

She liked yellow, maybe because of Texas, yellow being associated with the yellow rose of Texas. If you come from a specific place, and it's a place you love dearly you tend to want to identify with it. CAMPAIGN WIFE

PAT NIXON was a very practical woman. She did a lot of campaigning for her husband and separately from her husband, so that she was on the road a lot more than many of the first ladies had been.

Lady Bird was on the road a lot but not until after she became first lady. Mrs. Nixon had been traveling on the road and campaigning for her husband since the Eisenhower administration. She had been involved in active political campaigning outside on a national level, and so Mrs. Nixon was wearing the kind of thing that was practical, that was easy for her to keep up on the campaign trail.

I just don't see Richard Nixon as having the interest in how his wife appears that Johnson had, or having the intense masculine pride in how his wife appears that John Kennedy had for Jacqueline. Richard Nixon seems to have just trusted Pat to look right. And probably if you had asked him a day after what she had on the day before, he would not even be able to tell you other than he knew she looked fine.

Pat Nixon's own background had something to do with her style. She came from a family that didnt have very much as far as worldly goods were concerned. I imagine clothes were the least important thing in her life in growing up. There was not enough money in the family for her to be able to do anything more than be clothed and clothed decently -- as decently as she could on what they had available.

When they had the controversy about whether Nixon should continue for the second term as Eisenhower's vice president, somebody brought up the fact that he had a political fund that was supporting him, that was set up for his use by wealthy Republicans in California. And so some people were insinuating that there was something that was dishonest. When Nixon went on the air to refute this, he said that he and his wife lived very simply -- and all she had was the Republican cloth coat, which helped defuse the distrust.

Pat Nixon realized that she had gotten caught in a political cross fire as far as her Republican cloth coat was concerned, and, I suspect, was shaken up by it. But she did wear a fur coat and hat to the inauguration. And it didn't seem to have prevented her from wearing fur later on when she was able to afford it on her own.

If she preferred one color, it was probably blue. She looked pretty in blue with her blond hair and her blue eyes. Model of Comfort

BETTY FORD'S interest in ease of dressing had to do with her young children -- car pooling and taking care of everybody's interests when her husband was busy with his career. And the shirtwaist dress, which was definitely the style that she preferred, was just something that she was very comfortable in -- it was quite easy for her to wear. She had been a fashion model, so she had a model's instinctive interest in clothes and could wear them so that they looked well.

When she knew a style looked nice on her, she tended to trust her instincts and to wear that style -- different varieties of it. She loved a scarf around her neck. And the scarf became quite popular during the Ford administration.

When she suddenly became first lady she probably enjoyed having the opportunity to indulge her interest in clothes for a specific purpose amd being able to go to New York and select what clothes she wanted. And she probably enjoyed the opportunities a first lady has to show off fashion.

One of her favorite evening dresses was made from a piece of fabric that her husband had gotten for her from China when he went there as a member of the House committee -- after China was opened up during the Nixon administration. He brought her back a beautiful piece of green brocade, and she had a dress made by Frankie Welch in Alexandria.

She had told Frankie she liked the dress so much she wished she had more of the fabric because she'd like to have another dress just like it. Frankie found a second fabric in New York City. It's the same color exactly, the same design exactly, but it's not a brocaded silk; the design is embroidered on a silk chiffon. So she had the second dress made out of the fabric from New York. And it's the second dress that we have in the collection at the Smithsonian (of course she never had an inaugural ball), because that's the one she wore most at the White House. Office Partner

ROSALYNN CARTER saw her first lady's role as a job, as a career. She had her own office in the East Wing in which she worked. She dressed like a businesswoman. This was the way many women were moving. They were beginning to be more independent, to be seen as having a part in the career of -- as well as being a social adjunct to -- the husband. And so Rosalynn's clothes and the way she dressed reflect mainly a change that was happening to women all over this country.

She perceived herself as one of these women. She saw herself as having just as much of a job as the president did. It was a kind of partnership. What was new about her was that she organized the position into a business much more than the other first ladies. The other first ladies sort of went with the flow. They did the kind of thing they wanted to do, what was necessary. But they didn't see it as a career and a business. With Rosalynn you get much more the feeling of the modern career woman in how she approached the job.

She had a little bit of a more tailored, more practical look. And you have to remember that she came from a very small town in Georgia, and she was not comfortable with the New York fashion scene. She didn't want to be. She didn't think that was important. So when she wanted a formal dress she would probably be just as likely to go back to Georgia and get it from one of the stores down there as to go to New York.

The dress that she wore for the inaugural ball was the dress that she had worn when her husband became governor of Georgia -- at the inaugural ball in Georgia. The most interesting thing about that dress is that you can see the influence of first ladies' fashion on what's being worn elsewhere in the United States. Rosalynn Carter first wore that dress the same year that Richard Nixon was inaugurated as president of the United States. And Mrs. Nixon's inaugural ball dress certainly influenced the style of the dress that Rosalynn Carter wore as the wife of the governor of Georgia. It has the same little standing collar. The lines of the coat and the silhouette of that whole ensemble looked very much like the one worn by Mrs. Nixon.

NANCY REAGAN'S clothes, like those of Jackie Kennedy, caused a bit of a fuss. They both went to the top designers, the most expensive designers in the country.

People tend to go to somebody they trust and somebody that they have patronized before -- somebody they know helps them to look well. And Mrs. Reagan had been accustomed to dressing in high style since the days of her youth. She always dressed well, and she knew good clothes right from the beginning. So it's not any wonder that by the time she was an adult, and the Reagans had the money, she went to the best of the fashion designers.

Her first inaugural gown had been a gift to her from Galanos. It is an off-the-shoulder dress and is very hard to display -- but it certainly is a handsome dress.

By the second inaugural, she had learned a few things. The second dress had both shoulders in and she did wear her hair in its usual style. I think that she might have learned a little bit about Washington weather and that on the night of the inauguration there is the problem of going to seven different places and taking coats on and off and differences of temperature in each one of those ballrooms.

Her preference for the color red says that here's a woman who's not afraid to be noticed, that in fashion she rather likes to stand out in a crowd. It's in keeping with her self- confidence.

Her ensembles and well- coordinated look reflect the look of a woman of her generation. I think Jacqueline Kennedy's casualness -- in which she would have brown shoes and black gloves -- is a reflection of the casualness of youth and of the 1960s. Mrs. Reagan has come from an earlier generation. In my day you wouldn't think of having a handbag and shoes that didn't match. You dressed as an ensemble. And I think Mrs. Reagan still sees that as being the way to dress.

I don't know which sparks which -- whether having parties and enjoying parties sparks Mrs. Reagan's interest in formal dress or whether formal dress sparks the interest in parties. You'd have a hard time untangling that one. But I think that the Reagans come from a class of society where people do have big parties, and they just like to socialize. That's one of their relaxations at this stage of their lives. This is the way they like to enjoy themselves.