how to increase the number of cirtual desktops?

[Robert P. J. Day]

  i'm embarrassed to ask this, but how does one increase the number of
virtual desktops in f12?  used to be there were 4, but with f12, after
a fresh install, there's only 2 and i've poked around under
System->Prefs and don't see a setting for that.

rday
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Robert P. J. Day                               Waterloo, Ontario, CANADA

            Linux Consulting, Training and Kernel Pedantry.

Web page:                                          http://crashcourse.ca
Twitter:                                       http://twitter.com/rpjday
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