oily discharge

“Clouds of brown smoke from burning corn and the thatched root's of villages rolled across the battlefield under a gentle westerly breeze, streaked at intervals with the black, oily discharge of a flaming tank; the continuous rattle and chatter of small-arms fire was overlaid by a steady cannonade from the Russian 76-mm. 's and the scream of Katyusha rockets; periodically the high-pitched slap of the 88-mm. 's told of the Tigers 'defending themselves some three to four miles away.”

Barbarossa