title: Early detectors of the heart's electrical activity.
abstract: It was in Matteucci's rheoscopic frog in Pisa that evidence was first found for the electrical activity of the heart in 1844, and his results were confirmed and expanded 12 years later at Würzburg. The capillary electrometer gave a continuous record that could be photographed, and was used initially by Einthoven who, to obviate the onerous mathematical conversion of the electrometer record, developed the string galvanometer by the close of the century, and showed its clinical value in 1906.
authors.affiliation: Department of Physiology, NUI University College, Dublin, Ireland. caoimhghin.breathnach@ucd.ie
authors.forename: Caoimhghín S
authors.initials: CS
authors.lastname: Breathnach
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Westphal
mesh_terms: D000818:Animals; D004562:Electrocardiography / Q000266:history* / Q000295:instrumentation*; D004594:Electrophysiology / Q000266:history* / Q000295:instrumentation*; D005060:Europe; D006329:Heart Conduction System / Q000502:physiology*; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D049674:History, 21st Century; D006801:Humans; D014481:United States