cd /CDROM/comunity/audionav/africa ./earthsnd"earthsnd" is a client program. It will launch the NCSA Sound Server off the CD-ROM if it is not yet running; then it displays a window containing a map of Africa. This is a "waveable" map, not a "clickable" map.
On slower CD-ROM drives, you may hear occasional abrupt interruptions in the sound. If this happens, run earthsnd from a hard disk instead:
mkdir /tmp/earthsnd cd /tmp/earthsnd cp /CDROM/comunity/audionav/africa/* . ./earthsnd