Iron is the final peal of a star’s natural life.

In these days before antiseptics, doctors themselves also suffered high mortality rates. Florence Nightingale, a nurse during the Crimean War (1853-1856), watched one particularly inept surgeon cut both himself and, somehow, a bystander while blundering about during an amputation. Both men contracted an infection and died, as did the patient. Nightingale commented that it was the only surgery she'd ever seen with 300 percent mortality.

Never underestimate spite as a motivator for genius.

Lithium tweaks many mood-altering chemicals in the brain, and its effects are complicated. Most interesting, lithium seems to reset the body’s circadian rhythm, its inner clock. In normal people, ambient conditions, especially the sun, dictate their humors and determine when they are tuckered out for the day. They’re on a twenty-four-hour cycle. Bipolar people run on cycles independent of the sun. And run and run.

Iron is the final peal of a star’s natural life.

Mendeleev, unlike the squeamish Meyer, had balls enough to predict that new elements would be dug up. Look harder, you chemists and geologists, he seemed to taunt, and you’ll find them.

If anything runs deeper than a mathematician’s love of variables, it’s a scientist’s love of constants.