Last night, she started miming some sort of pump-action, two-handed squirt apparatus, but I wasn't paying THAT much attention to this gesture, since I was trying to figure out what my dozen monsters were up to that round. So I look up, and she's making a gesture as of squeezing both mammary regions, and saying "Sqrk, sqrk!" at whatever poor victim needed healing that round.
Things I did NOT know about artificers, volume 3. Their lactations heal the lame and cure the dying.