formidable were the great mechanical guards that still protected the place.
“See, there’s the patrol making the rounds the same as ever,” Otho commented. “Those monsters could make me grow hair!”
Captain Future nodded, raising the box he carried.
“It’s going to be risky, slipping past them. This contrivance may help us.”
They were within a few hundred yards of the Machine City. Seen thus close, the metropolis was a vast city that covered square miles of the desert, its brilliant towers looming up for hundreds of feet. Every building flamed with white light that was automatically maintained by machine engineers.
INSIDE the illuminated city was ceaseless activity. Moving sidewalks whirred smoothly through the lighted streets. Elevators in the buildings ascended and descended. Big metal trucks lumbered through the streets, depositing their loads automatically at their destinations. Other vanlike vehicles scooped up only the rubbish of time and carried it away.
Around the outer edge of the city there ceaselessly rolled a patrol of four-wheeled, carlike vehicles. Upon each was mounted a device like a small searchlight. The cars moved purringly, a hundred feet behind each other. These were the machine guards who protected the lost city of a dead race as they had been doing for countless ages.
The Machine City of Mars, blazing brilliant in the lonely desert beneath the hurtling moons, was tenanted only by the mindless mechanical devices who labored still for their stead masters.
“There’s a moral in this place for the rest of the System,” muttered the Brain. “Any people who rely too much on mechanical devices cannot but perish.”
“Well, I wish the people who built this joint had turned off their machines before they perished,” Otho muttered. Then he exclaimed: “Look at that sand-owl!”
Captain Future saw what Otho pointed at. A small Martian sand-owl was winging down to investigate the lighted city. The batlike creature alighted on a street just inside the city.
Instantly, with superhuman swiftness, one of the patrolling guard cars dashed toward the owl. The creature rose startledly on flapping wings. But the guard car was too quick. From its searchlight appliance, a pale ray smote accurately and blasted the winged creature. Then the guard car rolled back to rejoin the patrol around the city.
“Ice fiends of Pluto!” swore Otho. Did you see that? Those mechanical guard cars must be intelligent.”
“No, they’re just machines,” Curt said. “The old Machine-masters were cold-blooded. They built into their guards some kind of delicate thermo-couple instrument that was sensitive to warm-blooded life. It automatically makes them detect and kill intruders.”
Curt Newton was turning a switch in the side of the box as he spoke.
“This little generator will emit a heat shield that will prevent the guard cars from sensing us. But we’ll have to stay close together. Come on.”
With Otho, who still carried the Brain, directly beside him, Captain Future strode forward. As they approached the patrolling guard cars, Curt hoped fervently that his theory was right.
They skipped between two of the rolling cars. The mechanical guards made no movement toward them!
“Looks like you figured it right, Chief,” the android declared with a sigh of relief.
They entered the lighted streets. A huge truck was rushing toward them. They dodged hastily, but the truck automatically detoured around them. It was loaded with bolts of newly woven cloth.
Theaters were in full swing, the three-dimensional illusion shows constantly being made and presented mechanically. They heard recorded music of the old Martian type, weird, rippling arpeggios. But all the seats were empty.
SELF-STEERING vehicles rolled up to the doors of warehouses. They unloaded containers of synthetic foods, and took away similar containers whose contents had been untouched. Other mechanical workers rolled about, servicing the