Caesar’s Last Breath by Sam Kean

“It’s invisible. It’s ever-present. Without it, you would die in minutes. And it has an epic story to tell.

With every breath, you literally inhale the history of the world. On the ides of March, 44 BC, Julius Caesar died of stab wounds on the Senate floor, but the story of his last breath is still unfolding; in fact, you’re probably inhaling some of it now. Of the sextillions of molecules entering or leaving your lungs at this moment, some might well bear traces of Cleopatra’s perfumes, German mustard gas, particles exhaled by dinosaurs or emitted by atomic bombs, even remnants of stardust from the universe’s creation.

Tracing the origins and ingredients of our atmosphere, Kean reveals how the alchemy of air reshaped our continents, steered human progress, powered revolutions, and continues to influence everything we do. Along the way, we’ll swim with radioactive pigs, witness the most important chemical reactions humans have discovered, and join the crowd at the Moulin Rouge for some of the crudest performance art of all time.”

Along with Mary Roach and Bill Bryson, Sam Kean is one of my “must-read” non-fiction authors.  One of the things that has always made his writing stand out from the crowd for me was not only his storytelling ability, but the way he links many disparate tales into a cohesive whole.  For instance, in his last book, The Tale of the Dueling Neurosurgeons, his saga of neuroscience was structured to parallel the brain itself.  The vignettes illustrated functions and parts of the brain starting with the brainstem (unconscious functions) and moving ever upwards and outward to the most “human” parts of the brain.  It gives what can be dense science writing a flow that keeps you engaged, even if you have to take it slow to digest all the info you’re being given.

Unfortunately, this book doesn’t accomplish that nearly as well as usual.  Mostly this is due to Kean’s subject matter–the composition of air.  There is no inherent underlying structure to air, so there’s no ready-made framework for talking about it an a linear manner.  It seems to be sort-of arranged by how common each molecule is, from most common to least, but that’s not a scaffolding that lends itself to telling a comprehensive tale about air as a whole.  To return to my earlier example, while the brain can easily be visualized, air can’t.

The solution I found to enjoying this book was to read it in small chunks.  When I tried reading more than a couple of chapters at a time, I found my attention wandering–there wasn’t anything pulling me to the next chapter to see how the connections played out.  However, when I read a single chapter at a time and then put the book down for a while, I enjoyed it much more.  Because of this, I can’t really call the book’s structure a flaw.  It just means that I think it’s better if you read it piecemeal.  I will still say, though, that Kean did a better job with his earlier works when he was able to write something that you could read straight through and enjoy as a larger whole.

Even so, the stories are interesting.  One of the first ones is about a man who stayed on the slopes of Mount St. Helens until he was literally blown away by the eruption.  Another deals with a man who created an entire stage routine around farting.  There are intriguing tidbits about how sound bounces around the atmosphere, and why.  And of course, there’s the scientific breakdown of why you are probably breathing in molecules exhaled by Caesar as he died on the floor of the Roman senate.  That thought experiment alone is worth the price of admission, because it’s going to make you ponder what’s in your lungs right now as you’re reading this.

Although not one of his best works, Caesar’s Last Breath still has a lot going for it.  Just take it bit by bit and  you’ll likely enjoy this exploration of what’s in the air you breathe.

This book was provided by the publisher in exchange for an honest review.

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