Can CD-ROMS be indexed with OS 8.5?

[medtrans@yahoo.com (M. van Boxtel)]

Hi,
I have tried to make a large document backup on CD using the Sherlock
index facility (OS 8.5.1). The index of the archive made with Sherlock (on
a Jaz drive) was copied on CD along with the document folders. However,
even though the index was identified by Sherlock when the CD was inserted
I received an error notice when I tried to search for a keyword,
indicating that it was not possible to use the index. What went wrong
here? Is there a way to avoid this? Must indexed volumes always be
write-enabled?
Thanks!

Martin van Boxtel.