Arty would be the abbreviating for artillary (sorry Im military and that would irk me to to see rty)
Same goes for seeing BS instead of BB (battleship) and the like abbreviations for military acronyms. If you want me to relay the military list of abbreviations that can be used in Civ, I can do that in a heart beat
Thank you again for getting this on one page, Ive always hated seeing abbreviations without a prior context to it, not so much bad grammar (as if that doesnt happen on the internet) but Im one of the few that likes a reference, as if headcase said he pop (populated) a building, i wouldnt think of instabuild (an old unused term now adays) for quick finishing a building