Scenario:
A professor is preparing for a year-long sabbatical abroad and needs to take with her a book from the library that is critical to her research. The book was published in 1919 by an American university press. The faculty member is reluctant to borrow and take the library copy for an entire year, in case someone else might need it. Can she make a cover-to-cover copy of the book to use for her research?

Response:
Copyright law protects works for limited times. In the United States copyright of published works endures for the life of the author plus 70 years. After the expiration of this term a work falls into the public domain. In this case the publication is now in the public domain and may be copied without infinging on a copyright. It is safe to say that works published in the U.S. before 1923 are now in the public domain.