(The moving platform from 'A Visitor From the Twentieth Century' by Harold Donitz)

The scene was strangely familiar. The solution leaped to Markham's brain all at once.

"Why!" he cried, "such a street as this was described by a writer of my time!"*

"Then he was a prophet," said Warren, calmly, "It is not so easy to prophesy the inevitable."

"But," Markham continued, not having caught the guide's last remark, "he mentioned, I believe, streets a hundred yards in width and ten moving platforms in each direction, while you have here only five. Nevertheless the coincidence is . . ."

"We have such a street. It is called the Fifth Way, and was once known as Fifth Avenue, There are ten platforms in each direction, and the fastest move at a speed of nearly fifty miles an hour. But that is in the exact center of the island, and the outer platforms are used only by people desiring to travel from one end of the island to the other very quickly. As a man's residence, place of business, and recreation centers are all in the same building in most cases, there is very little cause for traffic between buildings. Two platforms for each direction, in fact, would be Sufficient to handle the traffic, were it not that the more platforms there are the higher the speed that can lie attained. Cross-town ways move at a lower level."