System Events equivalent to "list disks"

Question

I would like to mount a network share via AFP, but before doing so, I just want to check to see if it is mounted.
In my AppleScript 1-2-3 book, it tells me there is a command called "list disks"  when I execute it:
list disks
-- returns {"Macintosh HD", "A Disk Name Here", "A USB Drive Name there", "A Network Drive Name over here"}
basically, it works properly.
Now, in the book and on Apples's own site it says that "list disks is deprecated" and to use "System Events" instead.  It even gives me a sample command to try:
tell application "System Events" to get the name of every disk
it is supposed to return the same list as the command "list disks", but in my case, it errors out with an error message of -1000
What am I missing here?  I literally cut and pasted the command so I wouldn't make a mistake.

Answer 1

It works now....
I would type that exact command in
tell application "System Events" to get the name of every disk
and it would throw an -1000 error at me.  I even had a friend watch me to see if I was missing anything, but it still failed.  However, I did a reboot for something unrelated, and it started working.
However, it's a moot point.  I had a really bodgy workaround going but the whole script would stop functioning when the screen saver activated which is not what I wanted. 
So, in the end, I had to write a bash script so that it would run whether or not I was at the computer.  It actually seems to work better in bash than in AS.