London’s Science Museum in South Kensington was closed during the Second World War. When it reopened in 1945, the twelve-year-old Oliver Sacks discovered there the periodic table of the chemical elements. They were written in large letters on a wall, with samples of each element or one of its compounds attached to each name. That night Oliver could hardly sleep for excitement. To a boy who was already a keen amateur chemist, the revelation that the apparently disconnected properties of the elements could be fitted into a logical system gave the first sense of the power of the human mind. Sacks writes:
In that first, long, rapt encounter in the Science Museum, I was convinced that the periodic table was neither arbitrary nor superficial, but a representation of truths which would never be overturned, but would, on the contrary, continually be confirmed, show new depths with new knowledge, because it was as deep and simple as nature itself. And the perception of this produced in my twelve-year-old self a sort of ecstasy, the sense (in Einstein’s words) that “a corner of the great veil had been lifted.”
This sounds a little precocious for a twelve-year-old, but it reminded me of my own excitement when, as a student, I read Linus Pauling’s just-published book The Nature of the Chemical Bond. It transformed the empirical edifice of chemistry that I had been required to memorize into a science that could be understood, because it was based on fundamental properties of atoms, their sizes and charges, and the configurations of their electron shells, based on the new quantum mechanics.
The discoverer of the periodic system was the Russian chemist Dmitry Ivanovich Mendeleev. The romantic story of Mendeleev’s early career made him one of Sacks’s heroes. He was born in a small town in Siberia in 1834, the youngest of fourteen children. His father, the head of the local high school, went blind shortly after his birth and died not many years afterward. Dmitry’s mother recognized the boy’s outstanding talents and walked with the fourteen-year-old thousands of miles to Moscow to enroll him at the university there, only to learn that as a Siberian he was in-eligible for admission. The same happened in St. Petersburg, but there she finally found him a place in the Pedagogical Institute to train as a teacher.
Despite those setbacks, Mendeleev became professor of chemistry at the Institute of Technology in St. Petersburg at thirty, and four years later professor at the university there. In the same year, aged thirty-five, he published the periodic table as part of his monumental Principles of Chemistry. Mendeleev had begun by ordering the eighty-one elements known at his time in sequence according to their atomic weights. He noticed that many of their chemical properties were repeated at regular intervals, which led him to order them into horizontal rows and vertical columns. He placed the two lightest elements, hydrogen and helium, at either end of the first …