Thanks John B and Ralph and John S for your replies to my problem, which after I posted I calmed down enough to think of opening disk utility myself, and discovered the mounting thing. And John S, it was kind of interesting, what you said about the total disk ejecting. When I accidentally dragged my "precious" (that's its name) partition to the trash, I got a message saying it was in use and couldn't be ejected - right before it disappeared. I might add that it's a partition of the drive I was booted from, though not one with any system on it. When I opened disk utility my "precious" partition was greyed out, as were the other 2 I have, and DU said they were not mounted. The partition with X on it however was not greyed out. And, the other 2 still showed up on my desktop. Anyway, I would think that no way could you eject the partition you were booted from, but I guess you can eject other partitions. The main thing is that now I know they're just unmounted, not somehow deleted, which is what I had thought at first in my panic. margaret