I have obtained a photo of L. Papius symbols 163 for posting to my site.

http://www.bonannocoins.com/l_papius/l_papius_db.php

http://www.bonannocoins.com/l_papius/l_papi_coins.php?type_id=163

This coin is listed in CNR as 1/30 and the symbols are listed as seste / compasso retto which I think translates into English as pair of compasses / straight compass. Dick Schaefer suggests these symbols represent calipers. I agree, certainly for the obverse and also for the reverse since a compass can be used as a caliper.

http://en.wikipedia.org/wiki/Calipers

http://en.wikipedia.org/wiki/Compass_%28drafting%29

I am also in the process of going through CNR and posting a concordance between Crawford symbol numbers and CNR.