AUTOMATIC CHEMICAL ANALYSIS

The conference on automatic chemical analysis on which this monograph is based was held only a few days after the announcement of the award of the Nobel Prize in Chemistry to Jaroslav Heyrowsky. I t was thirty-five years ago that this distinguished Czechoslovakian scientist, working with Shikata, invented a machine to perform an analysis automatically. This machine recorded current-voltage curves automatically a t a dropping mercury electrode, and would tell the analyst not only what substance was present, in terms of the half-wave potential, but also how much! Any learned analyst of that time would have explained that this was not only absurd but impossible. Analysis was just not done in this simple fashion, and the general idea of automatic analysis, aside from its impossibility, seemed slightly indecent. To avoid the accusation of unwarranted cynicism, I report a personal experience illustrating the point. In 1938, more than thirteen years after Heyrowsky announced his invention, John Petras, a second-generation United States citizen of Czechoslovakian origin, and I were engaged in a study of polarography, in particular, the oscillographic presentation of polarograms. We showed that these phenomena could be displayed on a cathode ray tube screen. At about this time I was invited to address a physical chemistry colloquium a t one of our renowned metropolitan universities. As my title, I chose “Polarography.” Although I was an alumnus of the institution and its staff included old and respected friends, the invitation was almost withdrawn. As a result of my “take it or leave it,” attitude, however, my lecture was given. Petras and I brought along about 400 pounds of equipment to take, record, and project polarograms for the audience in an attempt to demonstrate Heyrowsky’s claims. The experiments were elegant and should have been convincing, but I think almost everyone in the audience felt that he was being subjected to some sort of electronic trickery. The thing that saved the day was my solemn resolve to give the complete mathematical derivation of the Ilcovic equation. This presentation was received with rapt attention and dignified approval, particularly because the equations were liberally punctuated with activity coefficients-all of which were canceled later by mutual agreement. I was congratulated on giving a very scholarly discourse and teased unmercifully for still believing that a machine could perform an analysis automatically. It is a matter of record that Heyrowsky’s visit to the United States in 1933 was frustrating and greatly discouraging to him. With a single exception,* instrument manufacturers were indifferent to his device and most analysts and physical chemists either did not believe in or scoffed at his idea. In the hands of a few United States chemists, however, interest in his subject slowly gained momentum and, a few years later, several instrument companies capitulated and built polarographs. * The E. H. Sargent Co.