Tom Koppel, the author of 2001’s Powering the Future, has always had a thing for tides, ever since his summer visits to Star Island as a child. Boasting only one tree on its barren flanks, the tiny island off the New Hampshire coast appealed to the young boy, who was intrigued by the rise and fall of its tides.
 

Now, in another country and at another shore – B.C.’s Southern Gulf Islands, to be exact – the author has finally written of his passion. Ebb and Flow is a book that has been in the making for more than 20 years, Koppel writes in his acknowledgements; the delay is the result of intermittent work, research, and interviews for magazines and newspapers. It’s been worth the wait.

Koppel, who has been praised for his ability to explain complicated science to the average reader, is doing it again. Beginning with the earliest human attempts to explain the phenomena of the oceans’ movements, carrying on through to Isaac Newton’s breakthrough in tidal theory in the 17th century, and on to the adventures of later European explorers as they learned firsthand that all tides are not created equal, the book mixes fact with personal experiences and observations.

Too much of the Coriolis effect, of Laplace’s mathematical analysis of the tides, and of the natural harmonics of physical systems can lose even the most avid reader, however. Koppel knows this, and often switches to interesting and more accessible tidbits – about the 163 boats wrecked in the infamous Seymour Narrows, for example – or to such tales as a heartthumping personal encounter with a whirlpool in Dodds Narrows.

He could have done with more help, however, from the book’s design. Copious uninterrupted pages of small-print text left me clamouring for more visual relief. The graphs and photos are as welcome as slack tide in Dodds Narrows, but like the author’s near fatal transit of this tricky passage, they come too late. An appendix would have been helpful, too.