Timothy Leary, 75, the former Harvard psychologist who became a national figure during the 1960s as the primary apostle of a cultic lifestyle based on the use of LSD and other hallucinogenic drugs, died of cancer May 31 at his hilltop home in Beverly Hills, Calif.

"Turn on, tune in, drop out," Dr. Leary declared, repeating this message so often that it became a mantra, striking a responsive chord in the young counterculture generation of the turbulent '60s. "You have to go out of your mind to use your head," he said.

Dr. Leary, who learned he had terminal prostate cancer in 1995, subsequently declared, "I was thrilled by the news," and said he was planning a "visible, interactive suicide" and a death day party in which his last moments would be videocast on the Internet.

But he died in his sleep, and his death was announced by friends on his home page on the World Wide Web, where he had provided regular updates on his condition and the legal and illegal drugs he was taking to ease the pain of his spreading cancer.

"Just after midnight, in his favorite bed among loving friends, Timothy Leary peacefully passed on. His last words were Why Not?' and Yeah,' " his friends wrote.

A major player in the anti-establishment ambiance of the 1960s, Dr. Leary was hailed as a visionary by his followers and denounced as a fraud and a charlatan by his critics. He infuriated mainstream parents by urging students to drop out of school. "All of our schools are paid for by middle-aged parents who want their children to become robots like them," he said in an interview with the British Broadcasting Corp. " . . . Drop out of school because schools' education today is the worst narcotic drug of all."

He spent much of the early 1970s in jail on drug charges or as a fugitive. In 1976, he was released from prison, but by then the war in Vietnam had ended and, with it, the anti-war movement. The "flower children" of the 1960s were beginning to age, and Dr. Leary's original constituency had dissipated. He never recaptured the public limelight he had held a decade earlier.

It was as a lecturer on the Harvard psychology faculty in 1960 that Dr. Leary first experimented with the hallucinogenic "sacred mushrooms" of Mexican religious rituals. He later would describe this as "the deepest religious experience of my life," and he decided to devote the rest of his career to developing the psychological benefits of mind-expanding drugs.

In 1961, he became interested in lysergic acid diethylamide, or LSD, a synthetic psychedelic drug based on a grain fungus, which first was developed in 1938. At Harvard, Dr. Leary began experimenting with LSD himself and giving it to colleagues and students.

Traditional psychology, he had concluded by then, didn't work. He later would call it "an arduous, ineffective, unimaginative attempt to impose the mind of the doctor on the mind of the patient."

Through his experiments with LSD at Harvard, he said, he had some success in treating alcoholism, schizophrenia and other psychophysiological disorders. But LSD also was becoming a popular underground drug on several college campuses, and Dr. Leary was emerging as its foremost advocate.

In 1963, he was dismissed from the Harvard faculty, along with a colleague, Richard Alpert, who later became known as Baba Ram Dass. They moved to Millbrook, N.Y., where they established a psychedelic drug study center in a 64-room mansion on a 4,000-acre estate donated by William Mellon Hitchcock, a descendant of financier Andrew Mellon. Anti-war protest leader Abbie Hoffman, poet Allen Ginsberg and authors Jack Kerouac and Aldous Huxley were among those who visited the facility.

In 1966, New York police raided the Millbrook Center and arrested four people for possession of illegal drugs. The raid was led by assistant prosecutor G. Gordon Liddy, who later would figure prominently in the Watergate case that led to President Richard M. Nixon's resignation.

After the raid, Dr. Leary, who had embraced principles of Hinduism on a 1965 trip to India, founded the League for Spiritual Discovery, which sought constitutional protection for the taking of LSD as a religious sacrament. The organization's manifesto described it as being "dedicated to the ancient sacred sequence of turning on, tuning in and dropping out."

Dr. Leary wrote books on the spiritual possibilities of drugs, including "The Psychedelic Experience: A Manual Based on the Tibetan Book of the Dead" and "Psychedelic Prayers After the Tao-te-ching," based loosely on a 3rd-century Chinese text. He wrote "High Priest," a diary of his major psychedelic experiences, and "The Politics of Ecstasy."

In a 1967 NBC documentary, he predicted: "We'll see an LSD orthodoxy in this country. You will see an LSD president. A pot-smoking Supreme Court."

In fact, some prominent establishment figures did experiment with LSD, including Time magazine founder and editor Henry R. Luce; his wife, playwright Clare Boothe Luce; actor Cary Grant; and comedian Steve Allen.

By the late 1960s, an estimated 1 million Americans had used LSD at least once, including 10 percent of all college students. There were about 50,000 people actively involved in the LSD movement.

Dr. Leary was born in Springfield, Mass., attended the U.S. Military Academy at West Point, then served in the Army during World War II and received a psychology degree at the University of Alabama while serving in the Army.

He received a master's degree in psychology from Washington State University and a doctorate from the University of California at Berkeley.

In 1955, he was director of psychological research at the Kaiser Foundation Hospital in Oakland, Calif. That year, his first wife, Marianne Busch, committed suicide by closing herself in the garage, starting the car engine and inhaling the exhaust.

In 1965, he was arrested in Laredo, Tex., and later in California on possession of marijuana charges. In the late 1960s, he ran unsuccessfully for governor of California.

He began serving prison time in California in 1970 but escaped and fled to Algeria and lived for a time with Black Panther Party leader Eldridge Cleaver. Later, he spent time in Switzerland and the Middle East but, in 1973, was apprehended by U.S. agents at the Kabul airport in Afghanistan and returned to the United States, where he was imprisoned until 1976.

Since his release, he had worked briefly in computer software development, appeared at nightspots as a stand-up comic and participated in a 1982 lecture-debate tour with G. Gordon Liddy.

A daughter from his first marriage, Susan Leary Martino, hanged herself in a Los Angeles jail in 1990.

Dr. Leary's marriages to Nena von Schlebrugge and Barbara Chase ended in divorce. In 1995, he remarried his third wife, Rosemary Woodruff.

Survivors include two sons. EDWIN L. DOUGHERTY Air Force Band Leader

Edwin L. Dougherty, 77, a retired Air Force Band leader who taught music at Prince George's County schools, died of cancer May 25 at his home in Accokeek.

Capt. Dougherty, an accomplished tuba player, directed the U.S. Air Force Drum and Bugle Corps in the 1950s as it performed in the United States, Europe and Asia. He was stationed at Andrews Air Force Base in the late 1950s and directed other bands before retiring from the military in 1961.

After his retirement, he became an instrumental music teacher at Eugene Burroughs Junior High School in Accokeek for 15 years. He then spent five years as a part-time instructor for several Prince George's schools, retiring in 1981. He lived in Melbourne, Fla., for 12 years until returning to Accokeek last month.

Capt. Dougherty, a native of Port Byron, N.Y., attended Ernest William School of Music in Brooklyn, N.Y., and graduated from Mansfield University of Pennsylvania. He began serving in the military in 1941 as an Army infantryman. Three years later, he was performing with the Army Air Corps Band.

His marriage to Evelyn V. Dougherty ended in divorce.

Survivors include five children, Carol A. Flewelling of Baden, Katherine E. Ludke of Accokeek, Jane E. O'Keefe of Knoxville, Md., Jay E. Dougherty of Bethesda and Jennifer A. Couchoud of Accokeek; a sister, Elvena Lyon of Auburn, N.Y.; a brother, Glen Dougherty of Port Charlotte, Fla.; and nine grandchildren. CARY DAVIS McDANIEL Manager and Former Teacher

Cary Davis McDaniel, 48, a tennis shop manager and former teacher, died May 30 at the University of Maryland Medical Center of injuries received in an automobile accident May 20 in Towson, Md. She was a lifelong resident of Alexandria.

A spokesman for the Baltimore County police said Mrs. McDaniel's Cadillac was hit head-on by a Nissan 300 ZX that had crossed the center line. Mrs. McDaniel's daughter, Katherine Randolph McDaniel, and another passenger, Kristin Seith, both 17, were treated and released, as were the other driver, Ernest Thomas, 24, and his passenger. Thomas was driving with a suspended license, police said.

Mrs. McDaniel had managed the Belle Haven Tennis Shop since the fall. She taught at St. Agnes School in Alexandria from 1973 to 1976 and was a former member of the board of governors of St. Stephen's and St. Agnes School.

Mrs. McDaniel, the former Cary MacRae, was a graduate of St. Agnes School and Smith College, and she received a master's in education from George Mason University.

She was a member of the board of governors of the Campagna Center in Alexandria and a member of Christ Episcopal Church in Alexandria, the junior auxiliary of Alexandria Hospital, Hunting Creek and Red Hill Garden clubs and the National Society of Colonial Dames.

Other survivors include her husband, John Douglas McDaniel, and son, Douglas Fairfax McDaniel, both of Alexandria; her mother, Elizabeth MacRae Hayes of St. Michaels, Md.; and two sisters, Elizabeth Fairfax Gouldin of Ithaca, N.Y., and Marion Montagu MacRae of Alexandria. THOMAS ALAN SULLIVAN Lawyer

Thomas Alan Sullivan, 88, a legislative lawyer for the Interior Department, died of cardiac arrest May 28 at the Jefferson retirement facility in Arlington, where he lived.

Mr. Sullivan was born in Pierre, S.D. In the 1920s, he moved to Washington.

He began his government career at the Commerce Department, while attending night classes at George Washington University. He received a law degree from National Law School, then joined the legal staff of the Interior Department, where he retired in 1967.

He was a member of the Civitan Club in Arlington and Walker Chapel United Methodist Church in Arlington. He was an avid golfer.

His first wife, Ruth Sullivan, died in 1967.

Survivors include his wife, Eloise Sullivan of Arlington; two children from his first marriage, Thomas Alan Sullivan Jr. of Nashville and Deborah Bottomley of Ramona, Calif.; a stepdaughter, Paula Gray of Fairfax; and five grandchildren. JOHN A. O'LEARY Air Force Officer

John A. O'Leary, 86, a retired Air Force colonel who later headed a trade association and a business management company, died of cardiac arrest May 28 at his home in Alexandria.

Col. O'Leary, who was born in Duluth, Minn., joined the Army Air Corps in 1940 and served in the South Pacific during World War II. He then worked mainly in personnel while stationed at the Pentagon from 1949 to 1951 and in Germany from 1951 to 1955. He was a member of the Air Force Logistics Command and then retired from the military in 1965 as a procurement officer.

He began a second career, first working in procurement for McDonnell Douglas for six years, and then moving to the Washington area in 1971 to serve on a congressional commission on government procurement. He became executive director of the National Contract Management Association and later served as president of Business Management Research Associates until his retirement in 1993.

He was a member of Blessed Sacrament Catholic Church and St. Rita's Catholic Church, both of Alexandria.

Survivors include his wife of 54 years, Adelaide L. O'Leary of Alexandria; a daughter, Betty Brigante of Boise, Idaho; three grandchildren; and a great-granddaughter. GEORGE K. LeBRUN Business Owner

George K. LeBrun, 87, who retired in 1986 as president of National Filter and Refill Co., a Beltsville cooling filter supply firm, died of a neurological ailment May 28 at a hospital in Florence, S.C.

He moved from Bethesda to Florence in 1994 and founded National Stamping Co., a manufacturer of hanger bars for moving equipment.

Mr. LeBrun was a native of Salem, Mass. He served in the Merchant Marine as a young man and was a salesman and a manufacturers representative. He designed and manufactured kitchen equipment after moving to the Washington area in 1939 and later owned Lesur Furniture Co. in Rockville. He founded National Filter in the early 1960s.

His wife, Rena Abbot LeBrun, died in 1986. Survivors include three daughters, Lorelei Redding of Kettering, Ohio, Jeralyn Labunaski of New York and Kennis Termini of College Park; two brothers, Francis and Jean, and a sister, Pat Michaud, all of Salem, Mass.; seven grandchildren; and seven great-grandchildren. FRANCES MORSE SLEEPER Church Member

Frances Morse Sleeper, 90, a member of St. John's Episcopal Church Norwood Parish in Bethesda and a World War II air-raid warden, died of pneumonia May 28 at Fairland Nursing Center in Silver Spring. She suffered a stroke in March at her home in Washington.

Mrs. Sleeper was born in York, Pa. She moved to Washington in 1926.

In 1928, she married Paul DeVoe Sleeper. He died in 1971.

Mrs. Sleeper was a civil defense volunteer and a bridge player.

She was a member of the Army and Navy Club in Washington.

Survivors include a daughter, Joan Sleeper Bandeen of Brookeville; nine grandchildren; and five great-grandchildren. A daughter, Jacqueline Sleeper Novak, died in 1985. CAPTION: TIMOTHY LEARY