They deal with the spectra of hydrogen and helium ... Three Lectures on Atomic Physics. By Prof. Arnold Sommerfeld s d. Translated by Dr. Henry L. Brose. Pp. iv + 70. (London: Methuen and Co ...

A Northwestern University-led international team of scientists has, for the first time, directly observed catalysis in-action ...

Balloons filled with hydrogen and containing metal salts are ignited. When the balloon explodes, the characteristically colored flame for that metal is seen. This is best performed outside or in a ...