Book excerpt: Time and Tide by Robert S. Ball is Ball's understanding of the moon and the tides. He uses diagrams and data to explain the linkage and science behind the movement of the tides. Excerpt: "Having been honored once again with a request that I should lecture before the London Institution, I chose for my subject the Theory of Tidal Evolution. The kind reception that these lectures received has led to their publication in the present volume. I have taken the opportunity to supplement the lectures as delivered by the insertion of some additional matter. I am indebted to my friends Mr. Close and Mr. Rambaut for their kindness in reading the proofs."