Three rare Irish books will be the main attraction at the inauguration of the Irish College's new library in Paris, writes Lara Marlowe

For more than 60 years, they rested in a bank vault in Dublin, all but forgotten by the trustees of the Irish College in Paris. No one is quite sure how the three rare books, the property of Ireland since 1802, reached Dublin, but they are believed to have been spirited out of the Latin Quarter for safe-keeping at the beginning of the second World War.

When Sheila Pratschke, the director of the Centre Culturel Irlandais, which is part of the Irish College, recently hand-carried the three heavy volumes back to Paris, they were insured for €100,000. To celebrate their return to the college library, which was designed by the royal architect François-Joseph Bélanger and opened in 1776, the Taoiseach will officially inaugurate the restored library on September 22nd.

Ireland inherited at least two of the three rare books from their fellow Celts, the Scots, by Napoleonic edict. All of Paris's English-speaking colleges were confiscated during the French Revolution. Napoleon Bonaparte had a soft spot for the Irish College, where his youngest brother Jérôme and stepson Eugène studied, and where Empress Joséphine and Madame Récamier used to dance.

So when Napoleon decided to restore the Irish College to the control of Dr John Baptist Walsh in 1802, he forcibly merged the pre-revolution English and Scottish colleges with it. He gave the contents of the English and Scottish libraries to the Irish, who'd lost their own books in the revolution.

This explains why the Flemish Psalter, circa 1500, and the chronicle of the descent of the kings of England from Adam and Eve until Richard III, are inscribed with the seal of the Scottish College.

Psalters became widespread from the third century on, when bishops decided the faithful could memorise the Psalms of David rather than the entire Bible. Priests' breviaries and most of the Latin chants were based on the Psalms.

It was common for Scottish patrons to commission illuminated manuscripts from the Flemish in the late 15th and early 16th centuries. The Irish College's Psalter is believed to have been ordered by a Scottish bishop from Antwerp or Bruges, and its 117 vellum pages are particularly splendid.

The opening page shows the bishop's coat of arms, followed by 12 pages dedicated to the months of the year and the signs of the Zodiac. An illumination of King David accompanies the first Psalm. On the opposite page is a breath-taking picture in rich medieval colours of Jesse, the father of David, dreaming. "An Irish person is immediately reminded of the Book of Kells," says Pratschke.

In Jesse's dream, a tree grows with the 12 apostles in its branches, surmounted by a medallion of the Virgin and Christ child. The wide golden border is decorated with flowers, birds and butterflies. Other illuminations in the Psalter include a lady and unicorn, jousting monkeys and two cherubs throwing arrows at birds.

The lineology of English kings is a unique example of English Gothic illumination. Its 111 pages include three full-page illuminations and many roundels, including the fall of the bad angels, the fall of Adam and Eve and Noah's Ark. All of the progeny of Noah's sons Sem, Ham and Japheth are listed; Japheth was the most prolific.

The smallest of the three treasures is a book of hours, the most common form of medieval illuminated manuscript. This one dates from around 1460, and though the full-page illuminations were sadly removed, it still contains exquisite miniatures and ornamental writing.

The books will be displayed in glass cases in the old library, which was renovated in 2002. Because the room cannot accommodate the 300 guests, the inauguration ceremony will take place in the garden. A diorama of the books will be set up under the arcades of the college, and guests will be able to read their contents on a computer screen.

The inauguration also celebrates the Irish government's €1 million project to restore the old library's collection of 10,000 volumes, to which the Bibliothèque Nationale de France has contributed several tens of thousands of euro.

The project is being supervised by the Irish College librarian, Carole Jacquet. Most of the 14th-17th century books are in Latin. Those published in the 18th and 19th centuries are in French, English and Irish. They include an Irish dictionary printed in Paris, complete with the fada, séimhiú and old Irish lettering.

Some 500 of the 10,000 books have already been cleaned. Not all - perhaps only 2,000 - will need work. "It's a huge job," says Pratschke. "The only way to do it is to throw money at it." About 20 professional book restorers are working full-time. "We have more work than the Paris ateliers can handle," she adds.

Some of the books are cleaned with very delicate brushes, some with a hand-held mini-hoover. Dirt is picked out of the cracks between pages with tweezers. Muriel McCarthy, an expert at Marsh's library, next to St Patrick's Cathedral in Dublin, has been consulted.

The project includes the sorting and storage of countless cardboard boxes of archives now kept in the vast cellars beneath the Irish College.

At the same time, the college has been granted €300,000 to convert its modern médiathèque into a lending library, in the hope of attracting more visitors. Its collection will expand from 1,000 to 10,000 books, CDs and DVDs.