The Man Who Weighed the Earth and Hid From His Housekeeper

Henry Cavendish discovered hydrogen. He determined that water was not an element but a compound. In 1798, using a delicate torsion balance in a sealed room, he measured the density of the entire Earth to within one percent of the modern accepted value. He was one of the greatest experimental scientists who ever lived.

He could not bear to be in the same room as another person.

Cavendish wore the same faded violet suit for decades to avoid any conversation about clothing. At Royal Society dinners, he would stand in a corner staring at the ceiling; if anyone approached, he would emit a small cry and flee. He crossed the street to avoid acquaintances. He left over twenty bundles of unpublished research in his papers — work that anticipated Ohm's law, Coulomb's law, and Dalton's law of partial pressures — because publishing meant dealing with people.

He was one of the wealthiest men in England. He spent almost nothing.

At home, he communicated with his servants exclusively by written notes. He ordered his dinner each day by leaving a message on the hall table. The message never varied: a leg of mutton. He informed his housekeeper that if he ever laid eyes on her, she would be fired.

One day, he glimpsed her on the stairs.

He did not fire her. He had a second staircase built.