"Sure! Baby ride merry-go-round." He started to step on the outer strip.
"No, no, Perry! Face against the motion of the strip. And step on with the foot nearest the strip." Perry safely negotiated the first strip. "Come on, Perry, off the edge of the strip. Get inside the red stripes at once. Otherwise you might interfere with someone changing speeds."
Perry looked down and saw that the center three feet of the strip was bounded by red stripes. Several people within earshot glanced toward them curiously at Diana's words, but turned quickly away, except for one small urchin about six years old who surveyed Perry with a slow dispassionate stare. The next four strips were traversed without trouble and they settled down on the cushions of the bench. Diana smiled at him. "All right?"
"Easy once you get the hang of it. Just Eliza crossing the ice." Diana gurgled. He watched with interest the passengers around him. The urchin who had favored Perry with his attention was now staring at the opposite bound traffic with his nose pressed against the glass backboard which rose above the back cushion of the bench. His mother steadied him with one hand while she talked with another woman. The traffic was fairly heavy and Perry watched them come and go with interest. His eye was caught by a plumpish middle-aged woman in a striking purple and white robe. She carried in her arms a bright-eyed shaggy terrier who wiggled and attempted to get down. The woman was looking back over her shoulder and talking to a companion. She collided with a man moving off the fifth strip, lost her balance and sat down very suddenly on her broad posterior just at the joint between the fourth and fifth strips where she lay, shrieking, while she turned slowly round and around. The terrier bounded away and attained the sixth strip, where he ran up and down barking at the passengers on the bench. As his mistress passed slowly out of sight, several other passengers helped her to her feet and brushed her off. Perry whistled to the dog, who acknowledged the overture by jumping to the bench beside him and applying a warm wet tongue to Perry's chin and neck, "Down, boy, down! That's enough." Perry grabbed his collar. "Now what do we do? We've been joined." He grinned. Diana rubbed the dog's head. Then she got up from the bench.
"Come along and bring your friend." She moved quickly to the fifth strip, Perry close behind, then to the fourth and to the third. She stopped on the second. "We should see her soon." Presently the purple and white robe showed up on the fourth strip. Diana, Perry, and the dog moved to the third and boarded the fourth as the woman came abreast. She swooped down on the dog.
"Chou-chou! Did mama's darling get lost? Was um fwightened?" She kissed its nose and hugged it. The dog wore an air of patient forbearance. "Thank the kind people, Chou-chou. They rescued you." She turned to Perry and Diana. Diana gave him a sidewise glance and tugged his belt. They skipped onto the fifth strip and quickly over to the sixth. Diana sat down and sighed deeply.
"Safe at last." They sat for a while and watched the passing buildings. A few minutes later she pushed an elbow in his ribs. "Look over to your left." She whispered. The purple and white robe was some yards away moving along the strip towards them. "I think she's looking for us. Come along. Here's where we get off." They threaded quickly through the crowd toward the outer strip and were shortly on the stationary walk. "That was close."
"Why was she looking for us?"
"Maybe she wasn't, but I took no chances. I can't stand to be slobbered over."
"What do we do now?" They were standing by the entrance of a large squat building of synthetic marble. Over the entrance Perry read UNITED STATS POST OFIS, Tub Stashon A. Diana followed his glance.
"Want to see how the tubes work?"
"Sure." They went inside, across a broad foyer and mounted a flight of stairs to a mezzanine. Diana led to the far side of the balcony. They leaned over a rail and looked down into a broad deep room whose floor level Perry judged to be below the street. Diana pointed down, and to the right.
"See them coming in there. Then they go on the belt and are sorted." Canisters of various lengths but of a uniform thickness, about eighteen inches, streamed out of a round hole and were deposited one after the other on a conveyor belt. Every few feet a mechanism leaned over the belt. Occasionally relays would click and a broad hook would roll a canister off the belt and pull it onto another belt running crosswise underneath the first. The crosswise belts then carried the canisters off to the right and left...
"Who operates the selectors?"
"They are automatic. An electric eye scans the destination tag. If the appropriate symbol corresponds, the grabber swings out and hooks off the can. See that first selector that is so busy? The one with three arms? That takes all the San Francisco traffic. Its belts unload in another room about as big as this where they are sorted for the local stations."
"I suppose the tubes run on compressed air."
"Only on short jumps. On the trunk lines they shoot along in a partial vacuum floating in a magnetic field that pulls them along. They make tremendous speeds on the long jumps."
"Suppose I wanted to mail a letter to New York. Would it ride in one of those cans all by itself?"
"Yes, but there isn't much sense in writing a letter when you can call up on the visiphone, or write on the telautograph."
"No, I suppose not. Say, I'd like to take one of those selectors to pieces."
"Perhaps you can if you care to apply for permission. But there is nothing fancy about them. Seen enough?"
"I guess so. What now?"
Diana glanced at a chronometer on the wall. "It's ten minutes past thirteen. We could run out to the rocket port if you like."
"Say, that's fine. Let's go!" They went back to street level and rode the first strip to an intersection where they dropped down one flight to the crosstown shuttle. This they took to a station marked TUB EKSPRES TU ROKET PORT. An attendant sealed them in a cylinder containing heavily cushioned chairs. Diana sat down and laid her head back against a head rest and told Perry to do likewise. A light glowed above them for a few seconds, then cut off. Perry suddenly felt very heavy and was pressed into the cushions. Then he was suddenly normal weight again.
"Brace your feet, Perry." The sudden increase in weight pressed him forward this time. Then normal weight returned and the door opened.
"Where are we?"
"At the port, about fifteen kilometers south of town."
"San Mateo?"
"No, west of there near Pillar Point." They climbed out and proceeded up a ramp to a waiting room, where swarms of people moved about and clustered at the far end. Diana glanced at an illuminated notice board and then at the chronometer beside it. "Hurry, Perry. We are just in time."
"For what?"
"The Antipodes Express. It arrives from New Zealand in four minutes. Hurry." He followed her up a ramp into a gallery with windows facing the field. Several sightseers were already there. Diana turned to one of them, a boy about twelve. "Is she in sight yet?"
"Uh huh, she's circling. See?" He pointed for them. Diana and Perry squinted at the sky.