What was going on when I was born?

The Board of Estimate yesterday barred new high-rise buildings on the residential side streets of the Upper East Side to protect the architectural character of the neighborhood. The new zoning law, approved unanimously, is the most sweeping zoning change in the area since 1961, when the previous zoning law took effect. Under that law, incentives encouraged buildings of 19 to 21 stories. The new law is intended to encourage buildings of six stories that match in height the brownstones, town houses and tenement buildings that fill the side streets.

A powerful earthquake struck central and southwestern Mexico early today, devastating parts of this city and three coastal states. The quake disrupted travel, commerce and communications and took a heavy toll of life and property. Unofficial estimates of the death toll ranged from 250 to several thousand. At least 1,000 were reported injured in Mexico City alone. But with only sketchy reports from the capital and many areas of the country cut off, the number of dead and injured was unknown. Tonight United Press International quoted Army and Red Cross officials as saying that they had recovered 64 bodies in Mexico City.

A report in the Briefing column of the Washington Talk page on Sept. 6, about the U.S.-Arab Chamber of Commerce, incorrectly characterized its Washington telephone number. The number - (202) 293-3162 - is in fact listed in the local directory.

Americans went on a buying spree in August, increasing their personal spending by the largest amount since April. But they financed the purchases by pushing their savings level to a record low, the Government reported today. The Commerce Department said personal consumption spending soared 1.2 percent last month as Americans rushed to take advantage of cut-rate financing incentives being offered by auto makers before the start of the new model year. The August spending gain was three times the July advance of four-tenths of 1 percent and was the biggest increase since a 1.3 percent rise in April.

A former New Jersey State Senator, reported to have vanished while scuba diving this month in the Bahamas, was indicted by a Federal grand jury today on charges that he and two other former state officials defrauded a teamsters pension fund. During the two and a half years of the purported scheme - from May 1982 to last October - the former Senator, David J. Friedland, was assisting a Federal investigation into political corruption in Jersey City and other communities in Hudson County, according to officials. Under a February 1982 agreement with the United States Attorney's office here, Mr. Friedland, facing a seven-year Federal prison term, became an informer. He had been convicted in 1980 of extorting $350,000 from an admitted swindler in exchange for a $4 million loan from the same teamster's fund involved in today's charges.

''Everybody and their brother wants to build on the Upper East Side, and unless you stop them, they will.'' - Assemblyman Alexander B. Grannis, Democrat of Manhattan, during a Board of Estimate zoning hearing. [A1:1.]

IT has the ingredients of a potboiler: A young woman from the Middle West, with no formal training, moves to New York and joins a publishing house founded by a brilliant but temperamental editor. He sells the house to a larger company, and is dismissed when his contract expires. The young woman takes his place, and the house seems to thrive. But employees start abandoning the company, and even the woman has sought a job elsewhere. Industry gossips wonder: Was she jumping or being pushed? Two years have passed since Eden Collinsworth, now 33 years old, became publisher of Arbor House, a small concern that the Hearst Corporation acquired from its owner, Donald I. Fine, in 1978. Miss Collinsworth, people who otherwise dispute her merits agree, is bright, savvy and ambitious. Up to that point, however, she had only publicized and marketed books; she had never signed up an author, edited a book or managed the finances of a company of any size. ''They took a flier on me, no doubt about it,'' she said in an interview this week. ''And it's worked out.''

LISTEN, dear reader, and you shall hear Of books and authors from far and near. Volumes galore put on display Along Fifth Avenue this fine Sunday. 48th to 57th will come alive; Browsing starts at 11 and ends at 5. ''New York Is Book Country'' is its name; For seven years now they've been doing the same. There'll be contests, games, quizzes, balloons, Drawings, raffles, posters, cartoons, Snoopy at work on a huge birthday card, A camel (alive) if you look very hard. And though the books can get lost in the hype, And brochures may seem the only things in type, Two-thirds of the booths will have works to buy - Just look for the sign: green balloons on high. (If you still can't find something for which to pay, There's always a bookstore along the way.) The fair's got entertainment up on a stage, Old books and new books, for every age. Rows and rows, just for antiquarians; A plethora of information for all those librarians. A special section just for kids And a 3 P.M. auction - make your bids. Publishers, booksellers, even small presses, Special events with prizes for guesses. A mobile post office for sending a gift - It should be enough to give friends a lift. Judaica, Hebraica, 20 booths on New York, And for the adventurous, a guided walk.

THERE are roughly 300 objects in the Whitney Museum of American Art's vast exhibition ''High Styles: Twentieth-Century American Design,'' and they range from chairs by Frank Lloyd Wright to chairs by Michael Graves, from turn-of-the-century punch bowls of ornate cut glass to a streamlined Electrolux vacuum cleaner from the 30's. There is a 1900 Tiffany lamp in the form of a spider web and a 1983 Frank Gehry lamp in the form of a fish, a silver dressing table from 1900 by William C. Codman and a plywood one from 1945 by Charles and Ray Eames. There is a 1925 Atwater Kent radio, a Philco television from the 50's, and a brand-new Apple computer. The exhibition's greatest strength is also its greatest weakness - it is so broad, so sweeping, as to mean virtually anything. It is intended to make the point that in this century, when American design came of age and could hold its own against the design traditions of Europe, it also had no clear and recognizable ''style,'' no single direction, and this comes through loud and clear. That our design tradition is a healthily pluralist one is impossible not to sense on the fourth floor of the Whitney, which has been turned into a great and joyous bazaar, chock-full of all kinds of different things that have probably never been under the same roof before.

The Economy Textile and apparel imports would be cut by up to 40 percent by a bill approved by a House subcommittee. President Reagan has denounced the measure and threatened to veto it. Speaker Thomas P. O'Neill Jr. predicted that the legislation would ''sail through the House'' in coming weeks, and Senate Republicans are also eager to move their version of the bill as quickly as possible. [Page A1.] Personal spending soared by 1.2 percent in August as Americans financed purchases by going deeper into debt and using savings, which fell to a record low. Personal income rose only 0.3 percent, the weakest showing since May. The sluggish income gains, low savings and high debt levels may doom Administration hopes that gains in consumer spending will propel the economy out of the doldrums, economists said. [D1.]

The Third Avenue Bridge, connecting the Bronx to upper Manhattan, stuck open during a routine test yesterday, causing ''near gridlock'' during the afternoon rush hour in the streets near its entrance. The one-way swing bridge, which carries nearly 60,000 vehicles to Manhattan daily, was closed at about 10:30 A.M. and remained shut into the night. It carries Third Avenue over the Harlem River from Bruckner Boulevard in the South Bronx to East 129th Street in Harlem.

Fourteen people were charged yesterday with paying or receiving bribes and kickbacks at New York City's Housing Authority, bringing to 56 the number of people accused this year in a widening inquiry into the agency's repair and maintenance program. ''The investigation is broad,'' said Patrick W. McGinley, the city's Investigation Commissioner. ''We will have more arrests to announce.'' Seven of those charged yesterday were current or former superintendents in the Housing Authority, bringing to 42 the number of authority employees who have been arrested in the inquiry.