capnomancy (n.)

"divination by smoke," c. 1600, with -mancy "divination by means of" + Latinized form of Greek kapnos "smoke," which is of uncertain origin, perhaps a non-Indo-European substrate word that also produced Lithuanian kvapas "breath, smell," kvepiu, kvėpti "to gasp, breathe," Latvian kvept "to smoke, smell," and perhaps Latin vapor.