The investments made by Ronald Read, a former gas station employee and janitor who died in June at age 92, "grew substantially" over the years, said his attorney Laurie Rowell.
Read, who was known for his flannel shirt and baseball cap, gave no hint of the size of his fortune.
"He was unbelievably frugal," Rowell said Wednesday. When Read visited her office, "sometimes he parked so far away so he wouldn't have to pay the meter."
The bequest of $4.8 million to the Brattleboro Memorial Hospital and $1.2 million to the town's Brooks Memorial Library were the largest each institution has ever received. Read also made a number of smaller bequests.
"It's pretty incredible. This is not something that happens on a regular basis," said the hospital's development director, Gina Pattison.
Besides cash, Read had an antique Edison phonograph with dozens of recording drums that he left to the Dummerston Historical Society, Rowell said.
"It's really a beautiful machine," said the society's president, Muriel Taylor.
Read was born in the small town of Dummerston in 1921. He was the first in his family to graduate from high school, walking and hitchhiking about 4 miles each way from his home to school in Brattleboro. After military service during World War II, he returned to Brattleboro and worked at a service station for 25 years and then 17 years as a janitor at the local J.C. Penney.
In 1960, he married a woman he met at the service station. She died in 1970.
Stepson Phillip Brown, of Somersworth, New Hampshire, told the Brattleboro Reformer he visited Read every few months, more often as Read's health declined. The only indication Brown had of Read's investments was his regular reading of the Wall Street Journal.
"I was tremendously surprised," Brown said of Read's hidden wealth. "He was a hard worker, but I don't think anybody had an idea that he was a multimillionaire."