When doing a file backup, 38.5MB is the largest file that can be
backed up using the Apple 40SC tape backup unit and Apple software.
An oversize (larger than 38.5 megabytes) file may not be backed up across
multiple tapes. It is possible to back up an oversize file using a
third-party utility, such as DiskFit from SuperMac Technologies.
For more information, search under: "SuperMac"