Conveyor Belts: "The Past Through Tomorrow" by Robert A. Heinlein

The Past Through Tomorrow - Robert A. Heinlein, Damon Knight

(Original Review, 1980-10-13)

People have complained about roads as conveyor belts as represented in Heinlein's THE ROADS MUST ROLL as being an inefficient means of transportation because of a number of reasons, some of those being energy efficiency and the problems of handicapped people using them. Instead of building them as a single conveyor belt, how about building them as a variable speed conveyor belt (by this I mean a conveyor belt that at different locations on it can have different speeds).
If you're into stuff like this, you can read the full review.