It never ceases to amaze me how far astronomical knowledge has come during my lifetime. Fred Whipple has taken an active role in the quest for understanding of those 'dirty snowballs', and his book 'The Mystery of Comets', charts the uncovering of the mystery. His book was published in 1985, and there has been a lot of frozen water under the bridge since then, but that doesn't diminish Dr. Whipple's own journey of discovery, and the weight of scientific facts contained here. The author covers the comet story from the ancients, to our modern times. The hairy stars of Homer and the Bayeaux Tapestry to Giotto's 'The Adoration of the Magi'. Our ancestors really did freak out about these strange apparitions in the sky. Whipple gives much more attention to the seventeenth century English astronomers than Carl Sagan did. Isaac Newton, John Flamsteed and the excellent Edmund Halley were giants, whose shoulders we all stand upon even today. As this book advances, the cometary science gets heavier. What are they made of? Where do they come from? When were they formed? Why do some comets seemingly defy gravity? Do comets die? Do comets seed life in the universe? Many questions still to answer today. Unfortunately the book ends in the mid eighties, just as Russian and Japanese probes were to be sent to intercept Comet Halley's mid-eighties return. Still, recommended for the astronomy buff, and read in good time for the Northern hemisphere observation of 103P/Hartley that will attain naked eye magnitudes in November next.