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Orbital Mechanics: Theory and Applications , T. Logsdon, John Wiley and Sons Limited, Baffins Lane, Chichester, West Sussex PO19 1UD. 1998. 268pp. Illustrated. £50.

The first three chapters deal with particles and groups of particles. The treatment of collision is questionable, otherwise it provides a good review. Chapter 4 covers Lagrange's equations and variational principles in a clear fashion. One section is headed Hamiltons' Principle but in fact deals solely with Hamilton's canonical equations. The next chapter is on rockets and space vehicles and contains some interesting examples of orbits and interplanetary trajectories. A section on electric propulsion is also of interest. The fundamental equation for a rocket in space is derived but the proof is logically inconsistent, also the remarks made regarding the stability of a rocket are false. (This is surprising because the book is published by the American Institute of Aeronautics and Astronautics.)