mounting disk problem

i am using Interactive Unix 4.1.1 and i have a disk from a another unix machine which is Unix Slackware 2.1 i'm having problem mounting the disk. it gives me an error message, ??? is there any solution to this ???

it say the disk has invalid file system

Different UNIX flavor use different file systems. You have to know the filesystem type before you mount. For example, most Linux systems (and your slackware) use the ext2 filesystem. To mount this on another platform you must mount it as an ext2 filesystem.

The above blurb is from the extensive manpage for mount on linux.

What is the type of filesystem you are trying to mount?