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Introductory Note to a Classic Article by Augustus D. Waller

August D. Waller was graduated from the University of Edinburgh with a medical degree in 1881. Dr. Waller made many contributions to physiology and medicine including the influence of anesthetic gases (ether and chloroform) on the irritability of nerves and muscles. He is best known for his recording and publication of the first human electrocardiogram in Journal of Physiology in 1887 entitled “A Demonstration on Man of Electromotive Changes Accompanying the Heart’s Beat”1 and reprinted in this history of cardiology section of Annals of Noninvasive Electrocardiology (ANE). The recording was made without opening the chest. The “electromotive changes” were recorded with a capillary electrometer built by Thomas Goswell, a technician in his laboratory. The capillary electrometer was invented by the French physicist, Gabriel Lippmann, in 1872. It is a thin glass tube with a column of mercury beneath sulphuric acid (Fig. 1). The mercury meniscus moves with varying electrical potential and is observed through a microscope and photographed. Because of the inertia of mercury, the movements of the mercury meniscus were severely damped, and this is evident in the figures in the accompanying article by Waller. A few years later, Dr. G. J. Burch of Oxford devised an arithmetical correction for the observed damped fluctuations of the mercury meniscus. The initial deflections prior to the correction formula were labeled A, B, C, and D. Einthoven used the term “electrocardiogram” at a meeting of the Dutch Medical Association in 1893 (later he claimed that Waller was the first to use the term; Lancet 1912;1:853–861). Einthoven, using an improved electrometer and an enhanced correction