A judge reversed himself Tuesday and released a 77-year-old woman from prison, conceding that her eight days behind bars failed to force her to reveal the whereabouts of her daughter and granddaughters. ``I can't imagine what will be more coercive than what the court has done in the past few days,'' Superior Court Judge Mark A. Pfeiffer said. ``I hope somehow you can look into your heart and your conscience and understand what is being done here.'' Mary Pigeon has insisted she does not know where to find her daughter. Her daughter, Elaine Yates, disappeared after a dispute with her husband five years ago. ``I feel much better,'' Mrs. Pigeon said after Pfeiffer's decision. ``I would win everything if my daughter and grandchildren would come home.'' She then went to her Warwick home. Mrs. Pigeon returned to court Tuesday on a request by the Corrections Department to confine her to home rather than keep her in prison. The request became moot with her release. Pfeiffer did not revoke his earlier order requiring Mrs. Pigeon to provide information about her daughter and granddaughters Kimberly, 8, and Kelly, 5. Mrs. Pigeon's son-in-law, Russell M. Yates Jr., believes Mrs. Pigeon knows where Mrs. Yates took the children when she disappeared from their Warwick home. Mrs. Yates left in 1985 after she found her husband with another woman aboard the family's boat. Yates, who did not attend Tuesday's hearing, has acknowledged hitting his wife and cutting her forehead with a ring, and that he had an affair with another woman. He won custody of the children when Mrs. Yates failed to show up to contest it. He sued Mrs. Pigeon after the custody hearing in an effort to find his daughters. After Pfeiffer concluded Mrs. Pigeon knew where her daughter is, he ordered her to pay a $23,000 fine. She has yet to pay it, but did comply with a later order to do 150 hours of community service. The judge's decision last week to send Mrs. Pigeon to prison provoked widespread criticism from women's groups, Gov. Edward D. DiPrete and others. Neil Philbin, Yates' lawyer, said he disagreed with the judge's latest decision but added, ``I'm confident Judge Pfeiffer ruled as his conscience guided him.'' Pfeiffer said he would listen to any ideas from Philbin about further penalties, but added he didn't know what else could be done.