Days and nights flashed by in a dreary monotony of mud, heat, insects and thinning rations. Then one morning the giant trees began to thin, and they passed from rainforest into jungle. The change was too late for Bucci. They carved a neat marker beside the trail, and set the dead youth's helmet atop it. Lieutenant Hague carried ahead a smudged letter in his shirt, with instructions to forward it to Wilma, the gunner's young wife. Hague and his four gunners followed the rattling whippet tank's trail higher, the jungle fell behind, and their protesting legs carried them over the rim of a high, cloud-swept plateau, that swept on to the limit of vision on both sides and ahead. * * * * * The city's black walls squatted secretively; foursquare, black, glassy walls with a blocky tower set sturdily at each of the four corners, enclosing what appeared to be a square mile of low buildings. Grey fog whipped coldly across the flat bleakness and rustled through dark grass. Balistierri, plodding beside Hague at the rear, stared at it warily, muttering, "And Childe Roland to the dark tower came." Sampler's tank ground along the base of the twelve-foot wall, turned at a sharp right angle, and the party filed through a square cut opening that once had been a gate. The black city looked tenantless. There was dark-hued grass growing in the misted streets and squares, and across the lintels of cube-shaped, neatly aligned dwellings, fashioned of thick, black blocks. Hague could hear nothing but whipping wind, the tank's clatter, and the quiet clink of equipment as men shuffled ahead through the knee-high grass, peering watchfully into dark doorways. Clark's whistle shrilled, the tank motor died, and they waited. "Hague, come ahead." The gunnery officer nodded at Sergeant Brian, and walked swiftly to Clark, who was leaning against the tank's mud-caked side. "Sampler says we've got to make repairs on the tank. We'll shelter here. Set your gun on a roof top commanding the street--or, better yet, set it on the wall. I'll want two of your gunners to go hunting food animals." "What do you think this place is, Bob?" "Beats me," and the navigator's wind-burned face twisted in a perplexed expression. "Lenkranz knows more about metals, but he thinks this stone is volcanic, like obsidian. Those lizard-men couldn't have built it." "We passed some kind of bas-relief or murals inside the gate." "Whitcomb is going to photograph them. Blake, Lenkranz, Johnston, and Hirooka are going to explore the place. Your two gunners, and Crewman Swenson and Balistierri will form the two hunting parties."