It is a chronology of things that haven't happened yet, like Robert A. Heinlein's famous story cycle, which came with a detailed chart of upcoming events going up into the year 2100.

它是尚未发生的事情的年表，例如罗伯特 A. 海因莱因 (Robert A. Heinlein) 著名的故事周期， 其中附有 2100 年即将发生的事件的详细图表。