Reply to mashine help - cant access my hard disk on osx

this is going to sound really basic but i cant seem to see what im doing wrong...
i cant access my external 1tb hard disk in machine on OSX?

when i click the disk button on the top left i only get my local harddisk contents not my external?

ive gone in to preferences and added my external as a location but it doesn't seem to show up!

im using a macbook air so space is limited with the ssd, on the external i have a range and samples and rex files im trying to import... can anyone help?