22 December 2010

Book review – The Planet in a Pebble

Posted by Dave Petley

A couple of months I was approached by the publisher of this book, Oxford  University Press, to ask if I would like a review copy and was intrigued.  The premise of the book is remarkable – that it is possible to write an engaging popular science book based around the geology of a single pebble.  And not an obviously fascinating pebble either – this is a piece of apparently dull, grey Silurian slate from Wales.  This is the sort of piece of rock that most geologists would ignore on a stony beach – and indeed the publisher also appears to have had misgivings about the subject as the cover (pictured to the right) shows a pebble that is most certainly not Silurian slate.  A slate pebble looks like the one pictured below.  Ironically, this can also be a beautiful piece of rock, so I cannot understand why the publisher has used such a misleading (to the geologist at least) image.

So I started wondering how such a book came about.  Was it a drunken conversation late one night on a field trip in deepest Wales (i.e. I imagine a cottage in the hills outside Lampeter, with a coal fire burning), in which the author and another geologist got into a bragging contest in which they tried to out-compete each other for who could write a successful popular geology book on the most obscure topic?  Probably not, but if so, the author Jan Zalasiewicz, certainly set himself a tough task!

So, does it work as a popular science book?  The answer is a remarkable and resounding yes.  The book is fascinating and engaging, stretching from the earliest foundations of time, in which the matter that now forms the pebble was created, to modern day beach environments.  Along the way the book describes the nature of modern geology, and in particular the detailed forensic investigations that are needed to piece together the history of our planet.  In so doing, the book overturns the popular myth that geologists are essentially visual scientists, doing little more than interpreting features based on observation and simple logical rules.  The great strength of the book is in the writing, which is at times beautiful, always engaging, and well-paced.  There is no sense that the book ever stalls – so often a problem in popular science writing – and the author manages to express his own love and fascination for the discipline.  I also appreciate the emphasis that the author placed on describing what we don’t know, as well as what we do.  We still have so much to learn, and it is important to communicate that fact.

That said, the book is not perfect, although the issues are perhaps niggles rather than major causes for concern.  First, the author is correct in stating that humans love a story, but we also need visual information in order to understand properly.  The book is under-illustrated, and those illustrations that are present are really rather weak and basic in comparison with the prose.  Perhaps the idea is to produce a fully illustrated coffee table version in due course (now that would be a wonderful tome) but for now the book is let down a little by this weakness.  The plates, in colour which is good, are frustrating in that the captions are at the start of the book.  That meant that when I came to the crucial passages  I found myself juggling between three different parts of the book, a most frustrating experience, if one that is good for developing hand-eye coordination skills!  In addition, the photographs mostly lack a scale bar or any other visual clue as to size – poor practice that is always criticised at undergraduate level.

Second, the end of the book, which details the period in which the pebble reaches the surface and encounters modern environments, feels rushed and somewhat sketchy.  Given that this is the environment in which we live, this is a shame.  It probably reflects the author’s own geological background, which is understandable, but it leaves a section that really feels weak in comparison to the rest.  And finally, in a couple of places the description of modern processes really feels a bit under-researched.  For example, we now know that the generation of fractures in rock masses by ice comes not from freeze-thaw but from segregation, and the idea that waves cause cliff disintegration through the generation of air pressures in fractures also has the feel of high school science.

But these are minor criticisms.  I would strongly recommend the book – if in the unlikely event that it was written as a bet then the author has undoubtedly won the prize.  I would buy it as a Christmas present, but would want to be sure that the recipient is au fait with at least basic science.  Jan Zalasiewicz undoubtedly has a talent for this type of writing, and I am sure many more books will follow.  I would not hesitate to buy the next one, even if it is on an equally obscure topic.

Comments from anyone else who has read it are welcome – do you share my views?