Hidden inside a simple brown case at the University of Toronto's Thomas Fisher Rare Book Library was a rare silver and gold embroidered Roman Missal. The liturgical book was designed in 1716 for the chapel of a wealthy Venetian family, the thread's silver colour now a dull grey and the pink ribbon markers have yellowed. The book is a rare example of an embroidered binding and yet its significance was never recorded in the library's catalogue – to the world it had ceased to exist.

The book's binding was discovered on Monday, the first day of the library's inventory – the first in 40 years – which aims to go through many of the library's 800,000 books in two weeks. Home to the rarest books in the country, the library is closed for this period, and librarians and archivists are gently, one by one, removing books and manuscripts off the shelves, organizing and looking for items that may have been misplaced, lost or stolen.

"As long as humans are doing their jobs, error is going to creep in, even if your staff is 99 per cent accurate all the time, there is still that 1 per cent and over 40 years things can go astray," said Pearce Carefoote, interim head of the department of rare books and special collections at the library. "The great thing is that when you are going through it, you learn that almost all of the books are where they are supposed to be and so you are just rescuing the ones that got lost through time."

Story continues below advertisement

The Globe and Mail was given access to visit the library on Wednesday to watch as the librarians worked away on the books, some of which lay flat on the shelves while others stood in rows. Below the lines of books, red rot from leather bindings was sprinkled on the tiles and shell-like pieces of the spines sat on the shelves, awaiting repair. Some librarians wore white masks to avoid the great amount of dust resting on the shelves and books, many of which hadn't been requested in years – a common fate since the library's collection is so large.

"A lot of the books that you will see are in boxes and so many times they are really nice surprises because they have very special bindings," rare-book librarian David Fernandez said. On his third day of shelving, he found a wooden and pigskin-bound book.

If a book is in a case, Mr. Fernandez, and the 14 other librarians, will make sure the book inside matches the flyer tag on which its call number is typed. Going through a printed catalogue sheet, they watch out for books that are either not on a shelf or misplaced. The librarians would then be on the lookout for the missing book or bring the misplaced item back to its home.

"Sometimes people get shocked that items go missing, but that is just the reality when you are dealing with 800,000 books," said Loryl MacDonald, interim director of the library. "The expectation is that they have been misshelved and that someone will find them."

A majority of the material in the library's collection has been donated as gifts from private libraries and estates. After a fire destroyed 30,000 rare books and manuscripts at U of T's University College in 1890, a tradition to donate items to the rare books collection was established, with even Queen Victoria donating a few books.

Margaret Atwood's original handwritten draft for The Handmaid's Tale was donated to the library as part of an archive collection housed in more than 600 boxes. The library is also home to Leonard Cohen's poetry and other writings, as well as a Babylonian cuneiform tablet from Ur from 1789 BC and Shakespeare's First Folio from 1623.

Mr. Carefoote found three misplaced books on his first day of shelving. One of the books, Speculum iuris, printed in Venice in 1576, was a commentary on the Code of Canon Law. The reason it was misshelved was very obvious, he said, as the number on the flyer was printed using an old standard typewriter in the 1970s, which made a letter in the call number hard to decipher.

Story continues below advertisement

A researcher from London, England sat in the empty library on Wednesday, as staff shifted through the books, which cannot be taken out of the library. Justine McConnell said she was given an exemption to work in the library, despite the closure, since she travelled so far to see the original work of Caribbean poet Derek Walcott.

"Unless you have been to the archives, you can't see his thought process, the many revisions and edits of his work, you get to see how he changes it as he goes along," said Ms. McConnell, who plans on using the material for a book about the poet. "You only get to see all this here in Toronto and nowhere else in the world."