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constant current circuits and in detecting circuits for end-point designation. In addition, some procedures for evaluating the time integral of transported charge have involved electronic principles or components. There has been a most encouraging interplay between fundamental chemical researches and instrumental progress in this field, apparently with each pacing the other. Following the definitive investigations of Lingane, the more recent work of Furman and coworkers has given an exciting view of the extension of coulometric techniques to the ultramicro region. Simultaneously DeFord and his associates have made a broad extension of the whole field, by developing a means for the external coulometric generation of reagents. There is scant sanction here for extended comment on their work [ANAL. CHBM., 23,938,941 (1951)],
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.but we cannot refrain from expressing great enthusiasm for this work and the conviction that it holds untold promise for analytical as well as instrumental progress. These authors have not only established the reliability and versatility of this mode of electrically generating reagents, but have extended the process to the completely automatic performance of titrations. Another field of wide applicability anticipated by these authors is the automatic generation of standard solutions, wherein electrical generation of reagent at 100% efficiency for a stated period of time and at constant current will yield a definite amount of reagent. It was von Helmholtz who first suspected the discrete nature of electrical charge, as a consequence of Michael Faraday's researches on the electrochemical equivalent. This century-old familiarity with the equivalence between electrical charge and particulate matter does not diminish our satisfaction with the promise that we can now visualize our reagents in purely electrical terms. Electrical quantities can be dispensed, controlled, counted, or recorded far more expeditiously than solutions can be handled. In the same connection, one suspects that the large field of electro-organic chemistry can be re-examined with profit. Many reactions with 100% electrode efficiency are known and others of potential value could be improved with the help of these very same techniques.
