Over Thanksgiving dinner, brothers and state legislators Paul and Jay Costa got into a friendly argument over what exactly had caused the skins to stick on a side dish of roasted chestnuts.

Several days later, Paul Costa found the answer -- the nuts had been cooked too long -- thanks to a 2-year-old state reference service called Ask Here PA.

And Mr. Costa isn't the only one using the online program.

At a news conference yesterday at the Carnegie Library of Pittsburgh in Oakland, state Education Secretary Gerald Zahorchak announced that Ask Here PA is the fastest growing program of its kind in the nation, receiving between 300 and 500 queries per day.

The service is a live chat, staffed 24 hours a day with librarians culled from 70 libraries statewide. It is on pace to be the most-used online state reference program in the nation, said Pennsylvania State Librarian Mary Clare Zales.

About 15 other states have similar services, but most have been in operation far longer than Pennsylvania's, said Ask Here Pa coordinator Vince Mariner.

At the news conference, Dr. Zahorchak asked the database its 125,000th question -- a request for the text of President Abraham Lincoln's Emancipation Proclamation and Farewell Address.

"It's probably one of the best kept secrets among the library arsenal of best kept secrets," said Dr. Zahorchak, noting that he's a frequent user of the site. One benefit of Ask Here PA over commercial sites such as Google and Yahoo is that users know that the information is accurate and unbiased.

To answer questions, the library service can access proprietary databases as well as the Internet. About 65 percent of the questions currently come from students in kindergarten through 12th grade, said Dr. Zahorchak.

In Allegheny County, the Carnegie libraries, the Duquesne University libraries and public libraries in Mt. Lebanon and Bethel Park are participating.

To access the online service, go to www.askherepa.org.