Codex Preservation

Codex preservation may be cast upon either a single book or a bay of books.  If cast upon a single book that book will be protected from the rigors of adventuring life.  The book is waterproof and unaffected by mundane environmental conditions, including ordinary heat, cold, humidity, mold, and decay.  If cast upon a bay of books at most 10x10 feet, the books will not suffer the wear and tear of ordinary use and storage.  If a book is kept continuously enchanted by this spell for a century, the effect becomes permanent.