How to use imap with gnus, especially how to get current email

[hsg@phy.duke.edu (Henry S. Greenside)]

Until recently, I was reading email with gnus (and
emacs) via pop, with the following entry in my .gnus
file,

   (setq gnus-secondary-select-methods '((nnfolder "")))
   (setq nnmail-spool-file '(  
     (pop :server "mail.phy.duke.edu" :user "hsg")))

but my mailserver has now switched to imap and ssl for
better security.

So I am now trying to using imap as a real imap server
rather than in pop or rmail style where the mail is
downloaded to a local file and then deleted from the
mail server. I tried to do this with the following
entry:
   
   (setq gnus-secondary-select-methods
         '((nnfolder "")(nnimap ""
   	  (nnimap-address "mail.phy.duke.edu")
   	  (nnimap-stream ssl)
   	  (nnimap-server-port 993)
   	  (nnimap-list-pattern ("~/Mail/*")))))

This worked (imap was able to detect my old mail groups
and connect to the mail.phy.duke.edu server) except
that I can't figure out from the gnus documentation or
from searching the web how to obtain my current email
from the imap server.

Is there a group that I have to subscribe to that
corresponds to my current email, e.g., by the name of
mbox or INBOX or something else? What do I have to do
to access my current email?

    Thanks,

    Henry