A reliable clarifier on scientific subjects (Submarines --Parachutes, etc.) now gives us the history, the past, present and probable future of rockets and jet-propelled planes. He explains in understandable terms, the basic principles, delves into early experiments (going back to 1232 AD); the role of different countries in this experimentation; he clarifies the differences. There are interesting sections on the bazooka, the V-1 and V-2, on anti-aircraft rockets. These are involved and difficult subjects to handle interestingly, but Mr. Zim has done a good job.