After graduating in 1948 from City College, Mr. Boublitz attended what was then Baltimore Junior College before enrolling at what is now Towson University, where he earned his bachelor's degree in 1953.
Drafted into the Army, he served from 1953 to 1955 with the Army Medical Corps at Fort Belvoir, Va., until being honorably discharged.
After leaving the Army, he briefly taught in Baltimore public schools before deciding to attend library school.
Mr. Boublitz had been a book collector since his teenage years. During his high school and college years, he worked as a page at the Enoch Pratt Free Library's Hampden branch. He enrolled at Rutgers University, which at the time was the closest library school to Baltimore. He earned a degree in library science in 1958.
"He left his wife and small daughters in the care of his parents and went off to New Jersey to study, returning home on weekends," said a daughter, Julia B. Morgan of Towson.
Mr. Boublitz began his career at the Pratt's Edmondson Village Shopping Center branch in the 4300 block of Edmondson Ave.
"Harry was my first boss at the Forest Park branch in 1968," said Vince Steadman, who retired in 2003 as manager of the library's Reisterstown Road branch and lives in the Bellona-Gittings neighborhood.
"He was an old-school librarian who was book-oriented. Harry was a very quiet guy who had firm convictions," said Mr. Steadman. "Every week, all the librarians had to go downtown to the book selection room at 400 Cathedral Street to see what books we might buy, and Harry had to review all the selections."
For several years, Mr. Boublitz was an executive assistant to Edwin Castagna, who was the Pratt's director from 1960 to 1975.
"Harry didn't like being a bureaucrat; he wanted to be out dealing with the public," said Mr. Steadman.
"He particularly enjoyed reference work and, in the days before Google, was known among librarians throughout the system as the go-to guy for answers on tough questions," said Ms. Morgan.
During his more than three-decade career with the Pratt, Mr. Boublitz worked at all 30 of its branches, including the central library at 400 Cathedral St.
He spent the last seven years as manager of the Hamilton branch on Harford Road and retired in 1991.
During his teen years, he began collecting Heritage Club and Folio Society books, which continued into adulthood.
"Books defined his life," said Ms. Morgan, who recalled the daily mail always bringing new books.
"The family rowhouse in Medfield Heights required braces in the basement to support a collection that grew to over 2,000 volumes," she said. "His tastes in literature were pretty catholic."
In addition, he collected books of American and English literature and belles-lettres. He was also a stamp collector who carefully labeled his albums with meticulous calligraphy.
Mr. Boublitz and his wife of 60 years, the former Carol Beck, were subscribers to the Baltimore Symphony Orchestra for 50 years.
Autumn Saturday afternoons allowed Mr. Boublitz to indulge in his two other passions: opera and football.
Mr. Boublitz enjoyed watching two football games on television while listening to the Metropolitan Opera Company broadcast.
"He'd turn the sound off on the football games while listening to the opera. It was pretty funny watching someone get tackled to the sounds of Wagner," said Ms. Morgan.
She said her father disliked Bob Irsay for moving the Baltimore Colts to Indianapolis but later became a "die-hard Ravens fan."
He and his wife regularly attended performances of the Baltimore Opera Company until it folded.
A memorial service will be held at 10:30 a.m. Oct. 26 at Holy Comforter Episcopal Church, 130 W. Seminary Ave., Lutherville.
In addition to his wife and daughter, Mr. Boublitz is survived by another daughter, Alison B. Wampler of Timonium; a brother, Robert Boublitz of Riderwood; two sisters, Barbara A. Pearce of Parkville and Carol H. Easton of Parkton; and three granddaughters.
An earlier version of this obituary inadvertently omitted the names of two surviving sisters. The Baltimore Sun regrets the error.