Marvin stood at the end of the bridge corridor. He was not in fact a particularly small robot. His silver body gleamed in the dusty sunbeams and shook with the continual barrage which the building was still undergoing.
He did, however, look pitifully small as the gigantic black tank rolled to a halt in front of him. The tank examined him with a probe. The probe withdrew.
Marvin stood there.
"Out of my way little robot," growled the tank.
"I'm afraid," said Marvin, "that I've been left here to stop you."
The probe extended again for a quick recheck. It withdrew again.
"You? Stop me?" roared the tank. "Go on!"
"No, really I have," said Marvin simply.
"What are you armed with?" roared the tank in disbelief.
"Guess," said Marvin.
The tank's engines rumbled, its gears ground. Molecule-sized electronic relays deep in its micro-brain flipped backwards and forwards in consternation.
"Guess?" said the tank.
Zaphod and the as yet unnamed man lurched up one corridor, down a second and along a third. The building continued to rock and judder and this puzzled Zaphod. If they wanted to blow the building up, why was it taking so long?
With difficulty they reached one of a number of totally anonymous unmarked doors and heaved at it. With a sudden jolt it opened and they fell inside.
All this way, thought Zaphod, all this trouble, all this not- lying-on-the-beach-having-a-wonderful-time, and for what? A single chair, a single desk and a single dirty ashtray in an undecorated office. The desk, apart from a bit of dancing dust and single, revolutionary form of paper clip, was empty.
"Where," said Zaphod, "is Zarniwoop?" feeling that his already tenuous grasp of the point of this whole exercise was beginning to slip.
"He's on an intergalactic cruise," said the man.
Zaphod tried to size the man up. Earnest type, he thought, not a barrel of laughs. He probably apportioned a fair whack of his time to running up and down heaving corridors, breaking down doors and making cryptic remarks in empty offices.
"Let me introduce myself," the man said, "My name is Roosta, and this is my towel."
"Hello Roosta," said Zaphod.
"Hello, towel," he added as Roosta held out to him a rather nasty old flowery towel. Not knowing what to do with it, he shook it by the corner.
Outside the window, one of the huge slug-like, gunmetal-green spaceships growled past.
"Yes, go on," said Marvin to the huge battle machine, "you'll never guess."
"Errmmm ..." said the machine, vibrating with unaccustomed thought, "laser beams?"
Marvin shook his head solemnly.
"No," muttered the machine in its deep guttural rumble, "Too obvious. Anti-matter ray?" it hazarded.
"Far too obvious," admonished Marvin.
"Yes," grumbled the machine, somewhat abashed, "Er ... how about an electron ram?"
This was new to Marvin.
"What's that?" he said.
"One of these," said the machine with enthusiasm.
From its turret emerged a sharp prong which spat a single lethal blaze of light. Behind Marvin a wall roared and collapsed as a heap of dust. The dust billowed briefly, then settled.
"No," said Marvin, "not one of those."
"Good though, isn't it?"
"Very good," agreed Marvin.
"I know," said the Frogstar battle machine, after another moment's consideration, "you must have one of those new Xanthic Re-Structron Destabilized Zenon Emitters!"
"Nice, aren't they?" said Marvin.
"That's what you've got?" said the machine in considerable awe.
"No," said Marvin.
"Oh," said the machine, disappointed, "then it must be ..."
"You're thinking along the wrong lines," said Marvin, "You're failing to take into account something fairly basic in the relationship between men and robots."
"Er, I know," said the battle machine, "is it ..." it tailed off into thought again.
"Just think," urged Marvin, "they left me, an ordinary, menial robot, to stop you, a gigantic heavy-duty battle machine, whilst they ran off to save themselves. What do you think they would leave me with?"
"Oooh, er," muttered the machine in alarm, "something pretty damn devastating I should expect."
"Expect!" said Marvin, "oh yes, expect. I'll tell you what they gave me to protect myself with shall I@"
"Yes, alright," said the battle machine, bracing itself.
"Nothing," said Marvin.
There was a dangerous pause.
"Nothing?" roared the battle machine.
"Nothing at all," intoned Marvin dismally, "not an electronic sausage."
The machine heaved about with fury.
"Well, doesn't that just take the biscuit!" it roared, "Nothing, eh? Just don't think, do they?"
"And me," said Marvin in a soft low voice, "with this terrible pain in all the diodes down my left side."
"Makes you spit, doesn't it?"
"Yes," agreed Marvin with feeling.
"Hell that makes me angry," bellowed the machine, "think I'll smash that wall down!"
The electron ram stabbed out another searing blaze of light and took out the wall next to the machine.
"How do you think I feel?" said Marvin bitterly.
"Just ran off and left you, did they?" the machine thundered.
"Yes," said Marvin.
"I think I'll shoot down their bloody ceiling as well!" raged the tank.
It took out the ceiling of the bridge.
"That's very impressive," murmured Marvin.
"You ain't seeing nothing yet," promised the machine, "I can take out this floor too, no trouble!"
It took out the floor, too.
"Hell's bells!" the machine roared as it plummeted fifteen storeys and smashed itself to bits on the ground below.
"What a depressingly stupid machine," said Marvin and trudged away.