"When I was asked if I would write it, I [said] I would be writing with prejudice - that I would be drawing on my own experiences and memories. Fortunately, I was given the freedom to write what I wanted."
The result is Freedom to Read: A Centennial History of Dunedin Public Library, a comprehensive history of the institution and the many characters who have inhabited its two buildings.
It was launched on Thursday to coincide with the library's centennial celebrations. Miss Ronnie was probably one of the few who could have tackled the book.
Her association with the library stretches back to 1937 when she joined as a 10-year-old newly arrived from Scotland, and she was a staff member for 34 years and city librarian for eight years.
She knew six of the eight city librarians, had already extensively researched the many private lending libraries which existed in Otago before the public library was established, and had written two previous books.
But she said she was not sure she should accept the job.
"When the library people first came to see me three years ago, I was 79 and I didn't know if I could muster the energy. They wanted the book written in two years, and having written books before, I wasn't sure that was long enough."
But accept she did, on the condition she was not paid for her work and that all royalties from sales went back into library funds.
"I wrote it because I wanted the library's history to be set down. If you get paid for doing something, it stops being fun and begins being just a task."
The next two years were spent "virtually 24/7" researching, interviewing and recording the important moments in the library's history.
Miss Ronnie included some of the stories of her own years at the helm, including her legendary run-in with the formidable A. H. Reed, who donated the library's world-class collection of medieval illuminated manuscripts and Bibles.
Mr Reed visited the library almost daily and still thought of the collection as his own, she said.
A heated argument erupted when Mr Reed decided he would rip another page from a rare Wickliffe Purvey Gospel edition (there were 32 pages missing already), frame it and put it on display elsewhere.
When Miss Ronnie objected, Mr Reed went behind her back, had a replica page printed and instructed a library binder to rip the original page out for him.
"The binder didn't want to do it and came to me in a purple rage. I told Mr Reed in no uncertain terms no more pages were to go, and that if he wanted to do that, he would have to take the book away from the library and return it to his own private collection.
"I won the argument. It didn't spoil our relationship, but it did make for a difficult few days."
Miss Ronnie, who is also a former New Zealand national librarian, said launching her book was pleasing, although she was more excited last year.
"I felt the achievement most . . . when I put the final full-stop on the final sentence."
The library has printed 800 copies, most of which are for sale. Others will be placed in the library reference room and others will be able to be borrowed.
The greatest praise would be for the lending copies never to be on the shelves, Miss Ronnie said.
"That is the ultimate for an author, isn't it - to have a book out and in use. The books I read as a child were battered because I loved them. Hopefully, my book will become battered too."
