Pasted among the pages was a small, black-bordered card that read: "admit the bearer" to the White House on Wednesday, April 19, 1865, the day of Abraham Lincoln's funeral service there.
It is believed to be one of only 600 such tickets printed, was highly sought at the time and may be one of the few still in existence.
Also among the pages were two brief notes from Lincoln that seemed to be pardons of a soldier for some unknown offense, inked with the distinctive "A.Lincoln" signature.
The documents are now available for sale via an online auction that started Thursday and ends Saturday. The auction site is MEARSonlineauctions.com.
Zook, who heads a Frederick-based business, "Mission: Transition," said the house was owned by descendants of an old Washington socialite family that once had been acquainted with the Lincolns. She declined to identify the family for privacy reasons.
With the agreement of the owners, she cleaned out the house several months ago, took boxes of items to her home and then began examining them, Zook said. There were old photographs, letters and the tattered leather-bound scrapbook.
"I'm a skeptic," she said, and when she saw the Lincoln notes, "deep inside me I said, 'These can't be real.' But they are. . . . I consider this some kind of cosmic miracle."
One of the Lincoln notes, dated Aug. 28, 1864, orders the suspension of the sentence in the case of a "Col. Law," for offenses that are not indicated. The other, dated January 1865, appears to order the pardon and return to duty for a soldier who may be the same man.
Troy R. Kinunen, president of the South Milwaukee-based auction firm, said he authenticated the written Lincoln items.
"They were all in [Lincoln's] hand," he said. Plus, they're "fresh to the hobby," he said. "Collectors like things that haven't been circulated. This is the first time they have been presented."
The ticket to the funeral service, which took place in the White House East Room before hundreds of mourners seated on chairs and specially built wooden bleachers, is especially unusual, he said. "The funeral pass was for a one-day event," he said.
Lincoln was shot April 14, 1865, in Ford's Theatre by actor John Wilkes Booth, who was angry that the South had lost the Civil War. Lincoln died the next morning.
Documents in Lincoln's handwriting are less rare, according to Lincoln scholar and collector James L. Swanson, whose 2010 book, "Bloody Crimes," chronicles Lincoln's funeral.
"During the war, he signed over 20,000 military commissions, thousands of civil appointments, thousands of autograph endorsements, plus many letters," Swanson said in an e-mail.
Still, "without knowing more about the stories behind them, I'd say the autographs are worth $3,500 to $5,000 each," he wrote.
Kinunen said the ticket is probably worth between $2,000 and $4,000.
Zook said the owners of the house, who will get any auction proceeds, did not want any of the items she found and instructed her to sell them. "Basically, they didn't want anything in the house," she said, although they're excited about the discovery of the trove.
"They just don't want it," she said. "They're not stuff people."