ABSTRACT
Among modern instrumental methods of chemical analysis, mass spectrometry has perhaps the longest history. The first mass spectrum was recorded in 1912 [1]. However, the mass spectrometers of today, with modern electronics, computerized operation, and multiple methods of sample introduction and ionization, have little in common with the instruments that were individually handcrafted in the laboratories of the 1920s and 1930s. The experiments of this era were primarily concerned with isotope measurements and the determination of appearance potentials.
