The valuable cloth-bound tomes entitled The O'Neills of Ulster, their History and Genealogy - published in 1907 in Dublin - had been left out for the binmen on a street in Vienna, Virginia.

The O'Neill books by Thomas Mathews, from the house of Sealy, Bryers & Walker in the Southern capital, had been tossed into four cardboard boxes outside a Victorian house along with first editions, unwanted anthologies, paperback classics and a vintage copy of Ulysses and collections of poetry by WB Yeats.

But before the binmen arrived book lover Pam O'Connor, passing by, spotted the treasure trove of literature and saved the lot for posterity.

She loaded the four boxes into her car and took them home, where she and her family examined the unwanted hoard which she found out had been the property of James C O'Neill, a professor of romance languages at the University of Michigan, who had died.

Whoever cleared the O'Neill house was obviously uninterested in the value of the books.

"These books would have been ruined in the heavy rain that fell that night if I hadn't rescued them," said Mrs O'Connor.

"I feel that somehow Mr O'Neill was intervening from somewhere. I know he would be happy that all his volumes are finding fitting homes instead of ending up a sodden mess at the dump.

"My husband and children and I stumbled on an amazing collection, as well as the unique O'Neill set, including beautiful illustrated tomes, books full of notations, an Irish Folk and Fairy Tales collection by Yeats. The Ulysses volume had been extensively annotated in pencil by Mr O'Neill."

Mr Swindall, whose JIRI Books company promotes the Belfast Book Fair every November, contacted Mrs O'Connor through an internet website and persuaded her to let him have the O'Neill three-volume set.

"I'm sure there is an O'Neill out there who has been searching for this extremely rare set for years," he explained.

"The last time a similar set turned up and was catalogued by a local book dealer was 1986 and it was snapped up immediately."

Book lovers and collectors and O'Neills who want to hear more about the O'Neill set can ring Jim Swindall on 9082 6443.