An underlying assumption of the CLASS Project from the beginning was that it would develop a network application. Project staff scan books at a workstation located in the library, near the brittle material. An image-server filing system is located at a distance from that workstation, and a printer is located in another building. All of the materials digitized and stored on the image-filing system are cataloged in the on-line catalogue. In fact, a record for each of these electronic books is stored in the RLIN database so that a record exists of what is in the digital library throughout standard catalogue procedures. In the future, researchers working from their own workstations in their offices, or their networks, will have access--wherever they might be--through a request server being built into the new digital library. A second assumption is that the preferred means of finding the material will be by looking through a catalogue. PERSONIUS described the scanning process, which uses a prototype scanner being developed by Xerox and which scans a very high resolution image at great speed. Another significant feature, because this is a preservation application, is the placing of the pages that fall apart one for one on the platen. Ordinarily, a scanner could be used with some sort of a document feeder, but because of this application that is not feasible. Further, because CLASS is a preservation application, after the paper replacement is made there, a very careful quality control check is performed. An original book is compared to the printed copy and verification is made, before proceeding, that all of the image, all of the information, has been captured. Then, a new library book is produced: The printed images are rebound by a commercial binder and a new book is returned to the shelf. Significantly, the books returned to the library shelves are beautiful and useful replacements on acid-free paper that should last a long time, in effect, the equivalent of preservation photocopies. Thus, the project has a library of digital books. In essence, CLASS is scanning and storing books as 600 dot-per-inch bit-mapped images, compressed using Group 4 CCITT (i.e., the French acronym for International Consultative Committee for Telegraph and Telephone) compression. They are stored as TIFF files on an optical filing system that is composed of a database used for searching and locating the books and an optical jukebox that stores 64 twelve-inch platters. A very-high-resolution printed copy of these books at 600 dots per inch is created, using a Xerox DocuTech printer to make the paper replacements on acid-free paper.