Mr Cornelius' large stock will be sold at a book fair organised by Turners later this month.
He will be taking particular interest in the fate of his favourite books. There's Trout Stream Insects of New Zealand by Norman Marsh - "a curious title," said Mr Cornelius. Rei Hamon, Artist of the New Zealand Bush and The Dictionary of New Zealand, Volume One 1769-1869 will also be auctioned.
The oldest book, Manchester Vindicated, was printed in Chester in 1749 - it was found in the library of the late Sir Adolphus Ward, principal of Owens College, and is a tale about vindicating Manchester from charges of Jacobitism and disloyalty.
Mr Cornelius said most of his books "walked through the front door" and he was selective about what he bought from his clients.
"People brought in far more books than I could hope to buy."
He didn't buy Mills and Boon, magazines, textbooks, Reader's Digest condensed books and encyclopedias.
"I always wanted to be a quality second-hand bookstore," he said.
American-born Mr Cornelius bought the Browsers store four years ago and he had to change its name.
At the time there were 30,000 books in the 180sq/m shop and he replenished the stock with another 10,000.
"You had to be willing to throw a book away and make room for another one," he said.
One of his first purchases was a collection of books from an estate in the Kaimais for $2500. Included in the collection was a copy of the Oxford English Dictionary in 14 volumes - he finally sold that a month ago for $1000.
Customers would come in and browse for an hour or two. They would sit on the couch and read, and even have a nap.
"That's the kind of shop it was. We didn't mind. The customers loved the environment, but it would have been nice if the store had made a profit," Mr Cornelius said.
A professor of chemistry, he came to New Zealand in 2003 and met his wife at a Single's Club in Hamilton. She died two years later.
Born in Chicago, he completed his doctorate at University of Wisconsin and his post-doctoral studies at University of Iowa. He taught and completed research into inorganic chemistry at Wichita State University and Lebanon Valley College in Pennsylvania - but he left that career in 2000.
So what will he be doing now?
"I haven't the foggiest," said Mr Cornelius. "I thought the bookstore would be part of the cultural hub of the city with the nearby cafes, public art gallery across the road and a private gallery next door.
"But the ROW Gallery has gone, and so has the bookstore. The town will be poorer for it."
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