GR translation: sucking on an egg

[Mike Jing]

V526.22-40   “What’s the deal?”
       “A minor piracy. Pick up one package for me while I cover you.” He
looks at his watch, hamming it up.
“O.K., get me a discharge, I’ll come with you.”
       “A what? A discharge? For you? Ha! Ha! Ha!”
       “You ought to laugh more, Springer. It makes you look really cute.”
       “What kind of a discharge, Slothrop? Honorable, perhaps? Ah, ah-ha!
Ha! Ha!” Like Adolf Hitler, Springer is easily tickled by what the Germans
call Schadenfreude, the feeling of joy at another’s misfortune.
       “Quit fooling, I’m serious.”
       “Of course you are, Slothrop!” More giggling.
       Slothrop waits, watches, sucking on an egg though he feels anything
but sly this morning.
       “Närrisch, you see, was supposed to go with me today. Now I’m stuck
with you. Ha! Ha! Where do you want it delivered, this—ha—this discharge?”
       “Cuxhaven.” Slothrop has been having lately this dim fantasy about
trying to contact the Operation Backfire people in Cuxhaven, to see if
they’ll help get him out.

What does "sucking on an egg" mean here?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://waste.org/pipermail/pynchon-l/attachments/20151220/aa943f11/attachment.html>