What was going on when I was born?

BOSTON A tall, slender, elegantly dressed Alger Hiss is confronting an ambitious young Congressman from California, Richard M. Nixon. The time is 1948, the place the House Un- American Activities Committee. ''I thought this committee was interested in ascertaining the truth,'' Mr. Hiss says acidly, replying to charges that he had been a Communist spy. What the truth of the Hiss case was bitterly divided America at the time. The dispute was one of the first major Communist-scare incidents; to this day, the case is considered far from closed in some quarters and is still able to stir partisan passions among both liberals and conservatives. The roots of the controversy is about to be re-created in a four-hour mini- series, ''Concealed Enemies,'' which will be shown on New York's WNET/Channel 13 beginning tomorrow night at 8. Produced by WGBH in Boston and starring Edward Herrmann as Mr. Hiss, the $4 million ''American Playhouse'' dramatization is the most ambitious non-documentary project undertaken by public television since ''The Adams Chronicles.''

awaited presidential election today, and in the final days of the campaign, the extent and propriety of the United States role was fiercely debated in both countries. Senator Jesse Helms, a conservative Republican from North Carolina, asked for the immediate recall of American Ambassador Thomas R. Pickering, accusing him of using his influence ''to strangle liberty during the night.'' Publicizing the Senator's critique, aides of Roberto d'Aubuisson, the rightist candidate in the election, complained that the American Embassy was responsible for the veto by Provisional President Alvaro Magana of legislation that would have allowed elections to proceed without requiring voters to go to the voting places where they were registered. Under the registration system, Mr. d'Aubuisson placed second in the March 25 election, well behind Jose Napoleo n Duarte, the Christian Democratic front-runner.

Sometime next month, reconstruction work on the dilapidated esplanade that runs from 71st to 81st Streets along the East River Drive should be finished and reopened to the public. Although the nine-month project is an upgrading of public property it is not costing the city a dime. The $1.7 million worth of new pavement and landscaping is being paid for by Harry Macklowe, the developer of a rental apartment house now under construction between 72d and 73d Steets, east of York Avenue. Mr. Macklowe's project, River Terrace, required a variance since his block-through property was zoned for residential use on its 72d Street side and manufacturing use on its 73d Street side. Part of the rezoning application process required that an environmental-impact study be done for the area around the project, which runs from 59th to 79th Street east of First Avenue and is called East Lenox.

JACKSONVILLE, Fla. JUST last month, the Charter Company, a $5.6 billion oil and insurance conglomerate that was once Wall Street's favorite, touted itself as a hard-charging, vibrant growth company. Its annual report, dated March 26, displayed a color photograph of smiling Charter chairman Raymond K. Mason, assuring shareholders that the company's ''financial condition continues to be strong.'' In truth, however, Charter was weak - very weak. Twenty-five days later, the company declared bankruptcy and, in so doing, ended a four-year high-wire act during which it had struggled to shore up its shrinking cash supply through financial gyrations while its basic business was slowly bleeding to death. The end of this corporate saga also closes a chapter in the colorful and volatile life of Mr. Mason, 57, a swashbuckling Florida legend whose penchant for deal-making transformed a small family lumber yard that he took over in 1963 into one of the nation's largest oil companies in the boom of the 70's. Mr. Mason was a king in his own world, shuttling between his castle in Ireland and a 60-acre former Du Pont estate here. He hobnobbed with the rich and powerful: Egyptian President Anwar el-Sadat came calling as did former President Gerald Ford.

THE city, with all it offers, can at times be overwhelming - driving even those who love it to get away for rest and refreshment. Some prefer to escape to exotic scenes, distant places that make New York fade until it disappears. But for many others, getting away means going to a second home, an oceanside bungalow, mountain chalet or farm retreat where life is as comfortable as faded jeans and well-worn boating shoes. Traditionally, second homes have been summer homes. But not anymore. Many people now use their getaway places for long weekends and holidays throughout the year, and developers, mindful of this, have responded by offering new houses that can be considered homes for all seasons.

A plan to erect a 29-story apartment house above the three-story New York Blood Center on East 67th Street will involve excavation procedures so delicate that workers will use picks and shovels rather than modern drilling tools. The age-old methods will be employed to protect the center's labs and sensitive instruments from dust, vibration and electrical interference.

STEVEN R. WEISMAN WASHINGTON S AVORING the rave reviews of his trip to China, President Reagan retreated from the stage for a rest at Camp David. His top advisers had no such luxury. They immediately began plans for the next openings on the re-election road show in an atmosphere of optimism and wariness. The President, several aides say, is performing so well politically that it is eerie. In spite of a bitter stalemate with the Soviet Union, a loss of American influence in the Middle East, immense controversy over Central America and a worrisome surge in interest rates, his approval ratings keep climbing. White House aides say the main reasons for Mr. Reagan's popularity are the economic expansion and the President's continuing ability to project an image of leadership and statesmanship. On the agenda of a White House political strategy meeting last Thursday was the content of television campaign spots to be aired starting May 21. Not surprisingly, they are to emphasize general themes of firmness of resolve and confidence in America under Mr. Reagan. Commercials with footage from the China trip concluded last week and the meeting with Pope John Paul II in Alaska are to come later in the year.

Swale, who spent much of the year in the shadow of his stablemate, Devil's Bag, posted an easy and decisive victory in the 110th Kentucky Derby today at Churchill Downs. His triumph was laced with sentiment and irony. Swale, a son of Seattle Slew and Tuerta who races for Claiborne Farm and is trained by Woody Stephens, scored by a handy 3 1/4 lengths under Laffit Pincay Jr. Coax Me Chad, an undistinguished member of the mutuel field, finished second, two lengths in front of At the Threshold. Gate Dancer was another neck back in fourth but was placed fifth for interfering with Fali Time, and the latter was moved up to fourth in the first such disqualification in the history of the Derby. Althea, who was sent off at 5 to 2 as the first filly to be favored in the Derby since 1935, led for the first six furlongs but then tired badly, was pulled up, and finished 19th. Other disappointing performances were those by Silent King, who finished ninth, Taylor's Special (12th) and Vanlandingham (16th).

It was a strange twist of events. With 1 minute 42 seconds remaining in the Nets' most critical playoff game, the center Darryl Dawkins fouled out, which on most occasions would have left New Jersey without enough muscle to handle the burly Bucks. But today, the Nets' backup center was better than the starter, and as Mike Gminski took the floor the cheers of the 14,623 fans swelled intensely. For in one of his best performances as a pro, Gminski scored 20 points and grabbed 9 rebounds - both career playoff highs - as the Nets rallied from a 16-point second- half deficit to score a 106-99 victory over Milwaukee at Byrne Meadowlands Arena.

Quentin Anderson, author of ''The Imperial Self,'' is writing a book on American views of personal identity. WALT WHITMAN The Making of the Poet. By Paul Zweig. 372 pp. New York: Basic Books. $18.95. THIS is no ordinary book on Whitman; it is the first successful attempt to show the nature of the chrysalis ''Leaves of Grass'' burst out of. The admiring and wondering Emerson first put the question: What could account for this fresh and startling voice? Floyd Stovall, in ''The Foreground of 'Leaves of Grass,' '' and others have patiently hunted out answers, but Paul Zweig is the first to take imaginative possession of the whole body of premonitory evidence in Whitman's stories, letters, notebooks, journalism, poems in draft, and has picked out what stirred the poet in his reading and in the world around him.

Last fall the developers of an office building going up at 900 Third Avenue, between 54th and 55th Streets, promised that the striking four-story greenhouse that started at the structure's 30th floor would be duplicated in a low-level annex planned for the corner of Third Avenue and 55th Street. The work was to start as soon as the apartment building on that corner, which is also owned by the developer, Progress Partners, was vacated and demolished.

-year-old Frank Zuraski's lips as soon as the boy came to the door. ''Got the books?'' Mr. Zuraski demanded. Ten-year-old Gary Williams shifted uncomfortably behind the screen door and looked at his feet. ''What books?'' he said. Then Mr. Zuraski showed him the blue computer printout he was carrying. It read, ''The New Book of Knowledge'' and ''The World Book Encyclopedia.'' Weeks overdue.