What was going on when I was born?

known Dorset lawyer, has left a $40 million estate to the National Trust, the independent foundation dedicated to preserving Britain's heritage. The bequest, the largest single gift the trust has received, includes 16,000 acres of farmland, an elegant 17th-century mansion containing one of the country's finest private art collections and the ruins of Corfe Castle, a historic fortress near the English Channel, parts of which are at least 900 years old. ''When the estate is opened to the public, it will certainly become one of the major attractions on the South Coast,'' said Warren Davis, a spokesman for the National Trust. ''The nation owes a tremendous debt of gratitude to Mr. Bankes.''

DALLAS AVATAR is 30 inches tall, weighs 85 pounds, moves around on a tricycle base, has a body made out of a 1940 Picker X-ray machine and lives in a frame workshop behind Charles Balmer's brick house just outside Urbana, Ohio. When all the circuitry is completed next year, Mr. Balmer will have spent five years building a robot whose chief attribute will be that it can wander around the 24-foot-by-30-foot workshop without bouncing off the walls. ''Its goal is survival,'' said Mr. Balmer, who is manager of software engineering for the United Systems Corporation of Dayton, Ohio. ''If it can learn to navigate on its own in a normal house and recharge itself when it needs it, I'll have done what I wanted.'' In the distant future robots may scrub toilets, wash the dishes and mow the lawn. Made-to-order robots can already be adapted to serve drinks at cocktail parties or vacuum on their own.

Members of the Senate gathered in somber session today to judge the fitness of Senator Harrison A. Williams Jr. to continue as one of their peers. Mr. Williams, Democrat of New Jersey, has been a member of Congress for 28 years. He was convicted last May of Federal bribery and conspiracy charges stemming from the Abscam investigation. Today he heard members of the Senate's Select Committee on Ethics charge him with bringing dishonor to the Senate by agreeing to use his office for personal gain. He listened with his hands folded as they urged the Senate to meet its ''solemn responsibility'' by expelling him. Before he entered the Senate chamber for the debate that could end his career, Mr. Williams, who is 62 years old, said he would insure that ''not only my conduct but also the misconduct of the F.B.I. will be fully examined.''

The Business Roundtable rejected the budget deficits projected by President Reagan as too large and asked Congress to reduce his proposed military buildup. The 46-member policy committee of the group, which represents 200 big corporations, was also said to have backed a deferral of the 1983 tax cut for individuals. (Page A1.) Mr. Reagan, stumping the nation on behalf of his program, warned that a move to rescind the tax cut would prolong the recession. (A1.) New car sales by the Big Three declined 26.9 percent in the final selling period of February despite continuing rebate programs. G.M.'s sales fell 35.3 percent, Ford's 10.5 percent and Chrysl@er's 8.2 percent. For the month, combined sales fell 14 percent. (D1.)

A roundup of quarterly earnings in Business Day on Feb. 22 incorrectly reported the results of Continental Group Inc. For the quarter ended Dec. 31, 1981, Continental had revenues of $1.2 billion and net income of $42.4 mil- lion.

A three-judge Federal panel today declared New Jersey's Congressional redistricting plan unconstitutional and ordered the Legislature to enact a new plan by March 22. The special panel, in a 2-to-1 vote, said the redistricting plan - signed into law in January by Gov. Brendan T. Byrne, a Democrat, just hours before Thomas H. Kean, a Republican, was sworn in as Governor - violated the constitutional doctrine of one man, one vote. Both houses of the New Jersey Legislature, which approved the plan, are controlled by Democrats. The court's ruling came in a suit filed by the state's seven Republican Representatives, some of whom would be forced by the plan to run against each other.

The State Department said today that the United States was seeking the right to use air bases in Colombia and Honduras, apparently as part of an effort to bolster the defenses of non-Communist nations in the Caribbean area. Disclosure of the Administration's plan came first from the Defense Department, which said it was asking for $21 million in the 1983 military construction budget for ''the purpose of airfield improvements in the western Caribbean area.'' Pentagon spokesmen declined to say what countries were involved, but Dean Fischer, the State Department spokesman, said, ''We are talking specifically in this instance about Colombia and Honduras.'' Use by U.S. Planes Foreseen Mr. Fischer said that the United States would seek permission to improve airfields belonging to those two countries and use them for training, search and rescue, and relief flights ''and for such other activities as agreed upon by the two countries.''

HE is a fabric designer and she is an artist who has just begun to design children's clothing. Yasushi and Kiyoko Suzuki met in New York, returned briefly to Japan and finally settled here about nine years ago. A visit to their loft in the East 20's, where they have been living with their twin sons since 1976, is a lesson in crosscultural interior design. Like other young, creative Japanese, three of whose homes are shown here, the Suzukis have forged their own personal design style. This means combining many of the traditions of Japan with an enthusiastic and vital view of the current American new-wave style. The result is an approach that is at once avant-garde and budget-conscious.

The Reagan Administration has begun an informal investigation to determine whether domestic manufacturers of the most advanced semiconductor chips should get some protection from intensified Japanese competition, Administration officials said today. Although the Government has taken some steps toward restricting imports in such basic industries as autos and steel, it has yet to act in high-technology sectors, such as semiconductors, where, until recently, American companies held a commanding world lead. Administration officials said that they were studying complaints by domestic producers, led by Motorola Inc., that the Japanese were''dumping'' tiny memory chips essential to computer operation at prices below fair value in the United States market. Semiconductor chips are pieces of silicon on which integrated circuits are printed. While there are numerous types of semiconductors and uses for them, those involved in the investigation are sophisticated memory and logic chips for computers. These are used for the key functions of storing data and peforming calculations.

A New Yorker who says she bought ''everything on impulse'' has given the Metropolitan Museum of Art one of the greatest private collections in this country of European art from the Renaissance and later periods. The cllection, said by outside experts to be worth $60 million, was gathered by Belle Linsky and her late husband, Jack, during 40 years. It comprises Old Master paintings, French furniture, porcelains, bronzes and Renaissance jewelry, many of them acknowledged masterpieces eagerly sought after by other museums, dealers and auction houses. ''We've known and coveted the collection for at least 20 years,'' said Philippe de Montebello, director of the Met. ''The level of quality is superb, and it includes many masterpieces that give a new dimension or a heightened character to the museum's holdings. From this point on, any publication that distills the Met's collections must make substantial references to the Linsky gifts.''

Although the International Business Machines Corporation prides itself on leading the way in the computer industry, it is following a path well trodden by others to enter the field of robotics. The licensing agreement I.B.M. announced last week to use a robot designed by Sankyo Seiki, one of Japan's least-known and financially weaker robot manufacturers, recalls similar agreements that helped many companies get started in this business before they had a robot on hand.

Pinehurst, the luxurious golfer's resort, rises out of the arid sand hills of south-central North Carolina like some desert oasis. Without warning, the bleak scrub brush landscape gives way to emerald fairways and vaulting pines. And with a turn off Route 1 from Raleigh, one leaves behind the real North Carolina of struggling tobacco farms for a fantasy land of stately villas, a country village, and almost painfully consistent good taste. Whether Pinehurst's tasteful traditions can survive is the present question. Documents are expected to be signed shortly to turn over the 87-year-old resort from its corporate owner of 12 years to an eight-bank consortium, led by New York's Citibank, which hopes eventually to resell it. The transaction involves assets of Pinehurst, valued at about $31 million, and an assumption of the corporate owner's $73 million debt.