Linus Pauling: The substances that make up the world are found as gases, liquids, solids, fibers, all various forms. For example, you have
brass or bronze in a doorknob, at least old-fashioned doorknobs, now perhaps there's steel with chromium or nickel plate on
it. In a brass doorknob there are atoms of copper and zinc held together. And one question that chemists have been interested
in for many years and I have been interested is why do these atoms stick to one another whereas the atoms of argon in the
air do not stick to one another; they are just bouncing around ten times as far apart, on the average, as if they were in
a sample of liquid or solid crystalline argon.
Well chemists formulated some rules. About 100 years ago, 110 years ago, an Englishman named Franklin said that for some reason
atoms of different elements are able to hook on to one another, a sort of hook-and-eye picture. When I first taught chemistry,
which was in 1918 I think, 1917, I was a student but I was asked by the teachers in Corvallis Oregon Agriculture College if
I would give some lectures at night to the students who had trouble with chemistry. And they said I'd get paid a few dollars,
a couple of dollars a night if I would give these lectures. So I said we could think of atoms as having hooks and eyes and
they hook into one another and that is the chemical bond between atoms.
Well at the same time I started college in 1917, when I was 16. In 1916, G.N. Lewis, Professor Gilbert Newton Lewis in the
University of California at Berkeley, had published a paper, very important paper, in which he said that the chemical bond
consists of two electrons held, lying intermediate between two atomic nuclei and holding them together. In 1919, when I was
teaching quantitative analysis in Corvallis, full-time, I had a full-time job for a year, I read the papers by Irving Langmuir,
important American chemist and very good ideas, really remarkable insight into chemistry. His papers were an amplification
of Lewis's idea of the shared electron pair chemical bond. Lewis felt that he hadn't added anything to his ideas but in fact
Langmuir did add a great deal in the way of getting a more detailed understanding of the structure of various molecules. I
became engrossed by this subject and I gave a seminar talk on the electron pair theory of chemical binding that year, when
I was 18 years old. And I think it was the only chemical seminar given the whole year, it wasn't a very active department
of chemistry there.
Then when I went on to Pasadena to the California Institute of Technology in 1921 I began research with Roscoe Dickinson,
who was a research fellow there, on the determination of the structure of crystals by x-ray diffraction. This method had been
discovered eight years earlier by W.H. and W.L. Bragg. W.L. Bragg, the son, was really the discoverer, he had the basic idea
and W.H. Bragg had the apparatus, he was working in the x-ray field already. It was a powerful method. It has become extremely
powerful now. At that time it was already powerful but not generally applicable because it was not a straight-forward method.