An Ocean of Air: A Natural History of the Atmosphere [Paperback]

Apart from the unoriginal title and misleading subtitle [any fourth-grader knows why the wind blows], this introduction to the history of atmosphere has much to recommend it. Walker is able to take us through the search for what comprises the air we breathe. She resurrects some important figures in this quest, showing why we should know of them. There are also familiar characters, not the least of which is Galileo, whose study of the air took his remaining years during house arrest by The Church. Although the challenge to cover so many characters and their efforts to put substance to something we consider almost ephemeral is daunting, the author covers the ground with spritely prose. The book is a good starting point for those unfamiliar with the air that sustains us.

It was a revelation of great magnitude to discover air can be weighed. Passing your hand through it doesn't seem to meet much resistance. Balloons and birds pass through it effortlessly, it seems. But the realisation that air was "there" was the first step in a long journey in understand what exactly was "there" to understand. Walker, although opening the account with Galileo's trial and confinement, reminds us that "air" was considered by some ancients, especially Aristotle, to be one of the four "Elements", along with earth, fire and water. Air, because it exhibits pressure, must have measureable "weight". Another Renaissance Italian, Alessandro Torecelli, resolving a dispute about that suggestion, invented the quicksilver [mercury] barometer still in use today - coining the phrase "ocean of air" as a result. In dealing with the pressure derived from its mass, Walker panders to her US readers by noting that Carnegie Hall in New York City holds over 32 thousand kilogrammes of air.

What naturally follows leads Walker to such scientific heavyweights as Joseph Priestly, Antoine Lavoisier, Joseph Black and even Gugliemo Marconi. Marconi? Why is the man credited with the invention of the wireless mixed in with gas investigators? Although Marconi wasn't certain how his signals could cover such vast distances, it was later learned that signals bounced from high altitudes. Whatever views we may have of weather events, Walker demonstrates, the upper atmosphere is in constant turmoil, with electrical and chemical changes occurring at intense rates. At each step in narrating the discoveries, she provides a descriptive segment on the life and thinking of the researchers. Her description of Oliver Heaviside will repel a few, but at this distance others will find him of interest.

Her focus is mostly on the science concerned with what comprises the atmosphere and its activities. Even so, it's disappointing that no mention is made of the earliest forecasters such as Robert Fitzroy, Darwin's captain on the HMS Beagle. Offsetting this lack, Walker brings to light a figure unaccountably forgotten. Early in the 19th Century, Virginian William Ferrel, who should have been doing his farm chores, instead studied mathematics and meteorology to decipher how the winds work. His calculations led to a new assessment of how air masses move due to the Earth's rotation. Today, the region of the atmosphere producing the winds and weather we experience daily is deemed the "Ferrel Cell".

Unlike some science writers, indeed, unlike some of her earlier books, Walker keeps herself out of this account - at least until the "Epilogue". The writing is vibrant and captures your attention. Occasionally, close scrutiny reveals some errors - "tropical" air cells do not originate at the Pole, nor was Columbus the "first European to step into a new world" - but these are minor glitches. The science story is well told and enthusiastically. Walker has done a great deal of digging into background material and guides us through the results almost effortlessly. This book would make an excellent gift to a young person looking for a career pursuit. But shop carefully as there are more thorough accounts than this one, no less well written. Much about "the ocean of air" has been explained, but even more remains. [stephen a. haines - Ottawa, Ontario]

This book is written in a 'chatty' manner that will no doubt annoy some people, but in my opinion adds a lot to the readability of this book.

Walker tends to explore a lot of tangets rather than stick to the main thread. (For example she goes into detail about Columbus's journey across the Atlantic to illustate trade winds.) However, these 'tangents' are still enjoyable, if not to the point.

I did find 'Snowball Earth' better (although noting from that ratings that view is not necessarily shared!).

This is a most interesting book about the History of Air - not at all the dull subject you might imagine but a fascinating story of how the unique and varied contents of our atmosphere were discovered by many famous scientists, sometimes against all the odds. and how important those discoveries were. Hydrogen the very first element in the periodfic table, Oxygen which we beathe every day and depend on, Ozone which protects us from damaging radiation from outer space and many others. Thoroughly enjoyed reading the book