Caesar’s Last Breath

Caesar’s Last Breath: Decoding the Secrets of the Air Around Us
© 2017 Sam Kean
384 pages

In The Disappearing Spoon, Sam Kean offered a history of early chemistry, as we began to understand the elements that create our world, and the hidden order in their atoms. Caesar’s Last Breath takes on a more intimate subject – the very air we breathe, and the multitude of stories that have erupted from its study, spanning Julius Caesar, volcanoes, and extraterrestrial colonization. Thoroughly entertaining, this mix of popular science and science history succeeds at bringing both the past and arcane equations to life.

Kean begins with a history of the Earth’s atmosphere – or atmospheres, since the early planet went through several before arriving at one suitable to our kind of life. The last big alteration was the arrival of oxygen, which was noxious to most life at the time and prompted a mass extinction. The atmosphere appears again of special interest later in the book, as Kean discusses the growth of meteorology, and the subsequent creation of chaos theory: despite all of the intervening scientific progress in isolating the components of our atmosphere and understanding the laws governing gaseous behaviors, weather has proven all bets are off.

Science and history are fused in Caesar’s Breath, which takes readers across the globe and across time. We stand in the Senate with the doomed dictator, visit an eccentric moonshiner and tourist host living in the shadow of Mount St. Helens, witness the eruption of gas warfare in 1915, and the even more explosive use of nuclear arms at the Bikini Atoll. The science is interesting in itself, driven as it is by a cast of characters – confidence men, social lepers, dogged engineers, ambitious businessmen, and a rascal or two – but Kean continually connects the scientific enterprise with its effects on human society, both for good and ill: although Kean includes a lot of war and disaster, here too we see the advent of medical anesthesia, and are presented considerable entertainment, like the man who convinced a host of trial patients that living in the same close quarters with cattle could cure their tuberculous.(“Living with cattle is the most delicious thing imaginable!” he said. The subjects disagreed.)

This is the second Kean book I’ve read and enjoyed, and I was impressed by the way Kean corralled a wide variety of subjects into one coherent narrative, one that doesn’t just rely on chemistry but connects with geology and meteorology as well. Kean’s other books are on stories connected to genetics, and then high crimes and misdemeanors associated with the pursuit of science itself.