John Coolidge, the son of President Calvin Coolidge and the oldest living offspring of an American president, died on Wednesday in Lebanon, N.H. He was 93.

John Coolidge was a man of few words, like his father, and spent most of his working life in private industry, including establishing and running a factory to make cheese using 19th-century methods at Plymouth Notch, Vt. The cheese operation was part of an effort he led to preserve the town where his father was born and sworn in as president.

''He bought property time and again when the state didn't have money, and it became part of the site,'' said John Dumville, chief of the Vermont Division for Historic Preservation, which runs the historic site.

When asked about a memorial for Calvin Coolidge, the president's father, Col. John Coolidge, always said that the town should be preserved. The effort started in 1956, when John Coolidge and his mother, Grace, gave the family homestead to the state.

After Grace died in 1957, John and his wife, Florence, continued donating. The site now has 25 buildings on 551 acres, maintained as they were when Calvin Coolidge was president from 1923 to 1929.

For the last two years, John Coolidge lived in a house in Plymouth Notch; the local residents, who number around 400, refused to identify it to outsiders to protect his privacy. Previously, he visited Plymouth Notch in the summer and lived in Connecticut the rest of the year. He would often turn up at the historic site to answer questions about the Coolidges, never mentioning that he was one.

''John Coolidge was very much like his father,'' said Howard Coffin, a historian in Montpelier, Vt. ''He was a man of few words but what came out was well chosen. He would, however, when speaking of his father and particularly of his childhood days at Plymouth Notch, go on at surprising length.''

One of John Coolidge's favorite stories was of the administering of the oath of office to his father, who was then vice president, at 2:47 a.m. on Aug. 3, 1923, after word was received that President Warren G. Harding had died the day before. It was done by the light of a kerosene lamp because Colonel Coolidge did not approve of electricity.

John Coolidge, who was attending a military camp in Massachusetts, was told the news as he waited in line for breakfast. ''Your father is president of the United States,'' the captain said.

''I was surprised, but nothing changed,'' John Coolidge recalled.

John Coolidge was born on Sept. 7, 1906, in his parents' home in Northampton, Mass. He was named for his grandfather. His father had originally been John Calvin Coolidge, but dropped his first name to avoid confusion and later legally changed it.

In his autobiography, Calvin Coolidge recorded his impressions of the birth of his first son: ''The fragrance of the clematis which covered the bay window filled the room like a benediction where the mother lay with her baby. It was all very wonderful to us.''

John Coolidge had a younger brother, Calvin Jr., who was born two years later. Robert A. Woods, a friend of the president, wrote in a book called ''The Preparation of Calvin Coolidge'' that John was a mechanical boy who built ''a recognizable automobile,'' while his brother stuck to playing his mandolin. Both did chores like mowing lawns and cleaning out furnaces for neighbors.

Tragedy struck the family in 1924. Calvin Jr. died at 16 after a blister from playing tennis led to a staphylococcus infection. Shocked Americans mourned the death, and even the famously taciturn president broke down.

As John Coolidge told Life magazine in 1992: ''Though father was tenderhearted, he rarely showed his feelings. But when they were taking my brother's casket from the White House after the services, my father broke down and wept momentarily. Calvin was my father's favorite. It hurt him terribly. It hurt us all.''

President Coolidge could be a tough taskmaster. He once wrote John at Amherst, where John was attending college, that he expected his son to work hard rather than dallying in nearby Northampton, home of Smith College, for women.

''I want you to keep in mind that you have been sent to college to work,'' the president wrote. ''Nothing else will do you any good. Nobody in my class who spent their time in other ways ever amounted to anything.''

Once when John was visiting at the White House, he mentioned at breakfast that he would not be dressing formally for dinner because he would be going to a tea dance that evening. His father was silent for a minute.

''You will remember that you are dining at the table of the president of the United States,'' he finally replied, ''and you will present yourself at the appointed hour properly clothed.''

More often, however, John Coolidge remembered his father, who died in 1933 at 60, as considerably folksier and wittier than many perceived him. In 1959, at a White House reception for presidential offspring, he told the story of passing a bank with his brother and his father.

''Boys, listen here for a minute and maybe you can hear your money working for you,'' Calvin Coolidge said.

In 1925, John Coolidge met Florence Trumbull, daughter of the governor of Connecticut, on a train bound for Washington and his father's inaugural after being elected president the previous November. They married in 1929 and named their first child Cynthia, so that the president's initials, C.C., would be perpetuated. Cynthia died in 1989. They had another daughter, Lydia Coolidge Sayles, who survives, along with three grandchildren and two great-grandsons.

John Coolidge worked for the New Haven & Hartford Railroad for 13 years, then started a business, Manifold Forms Company, which made business forms, in Elmwood, Conn. Two years after retiring in 1958, he reopened the Plymouth Cheese Corporation. His grandfather had been one of the original incorporators. John Coolidge sold the cheese factory to the state of Vermont in 1998.

A Republican, he held low-level party positions and made speeches and wrote letters to newspapers attacking the New Deal. He was a director of the Harvard Art Museum.

But he preferred a low profile. A 1949 article in The New York Times tells of the gangster Meyer Lansky's opulent suite on the steamship Italia, which he was taking to visit Lucky Luciano in Italy. The story noted that John Coolidge and his family were on the same boat and sailed cabin class.

John Coolidge always attended the annual commemoration of his father's birth in Plymouth Notch on July 4, 1872. He kept the ceremonies simple: a quiet procession, a few graveside words and a wreath-laying. Last summer, for the first time, he could not manage the stone steps to the hillside grave. But he watched from the family car nearby.