[.ca] Bones, Rocks, and Stars: The Science of When Things Happened (ISBN 0230551947)

The mysteries of time revealed:
In this series of evocative essays, Turney explains how our continually changing concept and use of time affects how we view the world and ourselves. Using a sprightly prose style, he opens with a description of various calendar systems developed by the ancients. It was difficult for them to reconcile the irregularities of lunar month, solar year and constantly changing heavens. Egypt, Babylon and Rome all struggled to maintain some control over the calendar. Many forms of adjustment were implemented but precision was difficult, if not impossible. The device of the "Leap Year" to adjust for the lack of precision was the best humans could do until the invention of the atomic clock. The atom, with many versions and intricacies, has proven an effective tool in time-keeping. From measuring split seconds to granting us some insight on circumstances billions of years ago, "atomic clocks" in their various forms have provided many solutions to long unresolved problems. Turney's chapter on the Shroud of Turin is but one example of a practical application. Its status as a forgery went undetected for centuries until radiometric measurements revealed its true age. A grander sweep of time, yet one with significant implications for today's world are the chapters on the eruption of Santorini in the Mediterranean and what led to the Ice Ages. Thera has been described as the cause of the elimination of the Minoan Empire. Based on Crete four thousand years ago, the Minoans operated an intricate network of trade routes in the region and were a highly sophisticated and successful people. Yet, they disappeared almost instantly around thirty-five hundred years ago. The author examines the evidence that Santorini might have been responsible. Further back in time, he reviews another threat to society in the form of invasive glaciers. Atoms play a role even in ice as accumulations of oxygen isotopes tell the story of climate change events. Even though some of those shifts rely on Earth's orbit and tilt relative to the sun, their signature rests with those oxygen atoms. Human societies have their own fluctuations, as Turney notes in other chapters. The dating of hominid fossils has contributed a great deal in deriving both the time and place of our origins. Rocks surrounding bones tell us when the fossils lived, and tiny grains of pollen indicate the type of environment they lived in. One of the enigmas of science is why there is but one species of upright-walking ape remaining - us. There have been competitors for living space, most notably the Neanderthals. But at least one other species co-habited the planet with us. The "Hobbit" fossil found on an Indonesian island resided there only 18 thousand years ago, as Turney's own dating research revealed. The possibility that there may be remnant populations yet to be found raises compelling questions. Turney's book may seem light-hearted at first glance, but it rests on serious work by dedicated workers. Dating the rocks was a difficult science in the 18th and 19th Centuries, but technology has provided astonishing new insights on our world. There's much to be learned and the author's effective presentation makes this book a stimulating introduction to this field. \ostephen a. haines - Ottawa, Canada\c

Exciting Cases Illustrating How Science Works:
In eleven thrilling chapters, the author discusses various methods by which items and events from the (extremely distant to not-so-distant) past can be dated. The limitations and uncertainties associated with each method are also touched upon. Each chapter presents a different topic, all real-life cases and some of which the author has actively participated in. The author has been very successful in conveying to the reader the methods by which science works and the excitement involved in scientific discovery. The writing style is clear, friendly, authoritative and very accessible. In fact, as a physicist, I probably would have explained the physics of a few things a bit differently and given more details; but then, this may have been at a cost - a loss in momentum and excitement for the general reader. So, clearly, this is a book that can be enjoyed by anyone, especially those interested in the scientific method.