Travel takes two forms. The first is the direct route, to get from one place to another as quickly as possible. The second is the meandering route, where one wanders about “to see more of what is going on in the world” (3).

In the future, a person will be able to step through a door in one city and come out in another city far away. The best way, though, is by balloon: You decide when to start and when to stop, and the balloon and the wind decide where you go. It’s a good way to travel to school because, more often than not, you have a fine adventure and end up somewhere else besides school.

The book’s hero is a 66-year-old professor of arithmetic from San Francisco, William Waterman Sherman. He retires, builds a balloon, and takes off in it, hoping to see some of the world. He lands on the island of Krakatoa in 1883; it’s a real island that actually blew up that year in the greatest explosion in history. People heard the boom 3,000 miles away; rocks were hurled 17 miles high, and the blast caused 50-foot waves; thousands near and far were injured or killed.