The grant is a gift from the Maryland State Library, the state department providing support for Maryland’s book lending institutions. If, as prison officials estimate, the average book costs about $20, the donation will fund the purchase of about 5,000 copies to be divided among the state’s 12 major prisons and four smaller satellite facilities. (There also are libraries in at least some of Maryland’s shorter-term correctional centers, according to a spokeswoman for Baltimore County, and in some cases, detainees can order books online. The $100,000 grant does not include book funds for these jails, most of which are locally operated and not part of the state prison system.)