Milestone-Proposal:String galvanometer to record the human electrocardiogram


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Docket #:2018-11

This proposal has been submitted for review.


To the proposer’s knowledge, is this achievement subject to litigation? No

Is the achievement you are proposing more than 25 years old? Yes

Is the achievement you are proposing within IEEE’s designated fields as defined by IEEE Bylaw I-104.11, namely: Engineering, Computer Sciences and Information Technology, Physical Sciences, Biological and Medical Sciences, Mathematics, Technical Communications, Education, Management, and Law and Policy. Yes

Did the achievement provide a meaningful benefit for humanity? Yes

Was it of at least regional importance? Yes

Has an IEEE Organizational Unit agreed to pay for the milestone plaque(s)? Yes

Has an IEEE Organizational Unit agreed to arrange the dedication ceremony? Yes

Has the IEEE Section in which the milestone is located agreed to take responsibility for the plaque after it is dedicated? Yes

Has the owner of the site agreed to have it designated as an IEEE Milestone? Yes


Year or range of years in which the achievement occurred:

Einthoven worked on the string galvanometer several years preceding the first publication of its operating principles in 1901 [1-4]. The first electrocardiograms made with the string galvanometer were published in 1902 and 1903 [5-6]. A breakthrough was achieved when a telephone-wire connection between the Academic Hospital Leiden (now Leiden University Medical Center) and Einthoven’s laboratory had been realized and ECG`s could directly be recorded from patients in the hospital. This „telecardiogram“ was first described in 1906 [7, 8, 9]. Details about the construction of the string galvanometer were described in 1908 [11, 12]. Several publications about the interpretation of the recorded electrocardiograms [10, 13, 14] established the physiological and medical value of this invention, leading to the Nobel prize for Medicine or Physiology in 1924. Einthoven’s Nobel-lecture [15] is an impressing overview of the physical principles underlying the galvanometer, its constructional intricacies, testing and engineering aspects. Overviews of Einthoven’s work can be found in numerous publications, amongst others in the obituary by Thomas Lewis [16], the biography by Herman Snellen [17], and the “Scanning our past” paper in the 2006 volume of the Proceedings of the IEEE by Dijk and Van Loon [18].

Title of the proposed milestone:

String galvanometer to record the human electrocardiogram, 1901-1905.

Plaque citation summarizing the achievement and its significance:

Invention of the string galvanometer electrocardiograph by Willem Einthoven (1886-1927), with which the first successful electrocardiogram in a patient in this hospital was recorded on March 22, 1905. The development of the string galvanometer by Einthoven marked the starting point of electrocardiography as a major clinical diagnostic tool. Einthoven, “Father of Electrocardiography”, was awarded the 1924 Nobel Prize in Physiology or Medicine.

In what IEEE section(s) does it reside?

Benelux Section

IEEE Organizational Unit(s) which have agreed to sponsor the Milestone:

IEEE Organizational Unit(s) paying for milestone plaque(s):

Unit: Benelux Section
Senior Officer Name: Senior officer name masked to public

IEEE Organizational Unit(s) arranging the dedication ceremony:

Unit: Benelux Section
Senior Officer Name: Senior officer name masked to public

IEEE section(s) monitoring the plaque(s):

IEEE Section: Benelux Section
IEEE Section Chair name: Section chair name masked to public

Milestone proposer(s):

Proposer name: Proposer's name masked to public
Proposer email: Proposer's email masked to public

Please note: your email address and contact information will be masked on the website for privacy reasons. Only IEEE History Center Staff will be able to view the email address.

Street address(es) and GPS coordinates of the intended milestone plaque site(s):

Leiden University Medical Center,

Albinusdreef 2, 2333 ZA Leiden, The Netherlands.

Coordinates: 52.166128, 4.477316

Describe briefly the intended site(s) of the milestone plaque(s). The intended site(s) must have a direct connection with the achievement (e.g. where developed, invented, tested, demonstrated, installed, or operated, etc.). A museum where a device or example of the technology is displayed, or the university where the inventor studied, are not, in themselves, sufficient connection for a milestone plaque.

Please give the address(es) of the plaque site(s) (GPS coordinates if you have them). Also please give the details of the mounting, i.e. on the outside of the building, in the ground floor entrance hall, on a plinth on the grounds, etc. If visitors to the plaque site will need to go through security, or make an appointment, please give the contact information visitors will need. The intended site is the entrance hall of the Leiden University Medical Center (LUMC), previously the Academic Hospital Leiden. On this location, the first human electrocardiogram was recorded in 1905 from a patient connected via a telephone line to the string galvanometer which was placed in the laboratory of Willem Einthoven (1886-1927). The development of the string galvanometer by Einthoven marked the starting point of electrocardiography as a major clinical diagnostic tool. Willem Einthoven, “Father of Electrocardiography”, was awarded the 1924 Nobel Prize in Physiology or Medicine.

Are the original buildings extant?

The present hospital (Leiden University Medical Center, LUMC) has been built at the same location as the original Academisch Ziekenhuis Leiden (AZL), where the first telecardiogram was recorded.

Details of the plaque mounting:

We intend the plaque to be mounted at eye level on a pillar in the entrance hall of the Leiden University Medical Center, where the first cardiogram from a patient was recorded via a telephone link and using the string galvanometer. The pillar (see Fig.1) is a few meters from the door of the main entrance.

Fig.1 The position of the plaque in the entrance hall of the Leiden University Medical Center. In the background is the reception desk.

How is the site protected/secured, and in what ways is it accessible to the public?

The LUMC is publicly accessible, but there is permanent surveillance by guards and video camera.

Who is the present owner of the site(s)?

Leiden University Medical Center (Leids Universitair Medisch Centrum).

What is the historical significance of the work (its technological, scientific, or social importance)?

Worldwide, 12-lead 10-second electrocardiograms are routinely made when a patient sees a cardiologist, and on many other occasions, including emergency situations like acute coronary syndrome (acute myocardial infarction), where the electrocardiogram contributes to important triaging decisions. Additionally, electrocardiography has new applications, e.g., in intensive care monitoring and in long-term ambulatory monitoring, the latter, e.g., for the purpose of the detection of cardiac rhythm disturbances. Thus, electrocardiography, and various forms of electrocardiographs, have become an important and indispensable part of medical practice. The three “Einthoven leads” (the electrocardiographic derivations as originally used by Willem Einthoven, using electrodes at the right and left arms and at the left foot) still constitute part of the current standard 12-lead electrocardiogram. By recording and interpreting electrocardiograms in a variety of patients and volunteers, and by commercially producing various copies of his string galvanometer, Einthoven was literary instrumental in the quick rise of interest of clinicians in electrocardiography.

What obstacles (technical, political, geographic) needed to be overcome?

The string galvanometer was developed by Einthoven to record the electrical current generated by the heart, and derived by electrodes on the body surface: the electrocardiogram (ECG) [1]. Einthoven and his contemporary international colleagues working in this field faced the problem that their equipment had to be sensitive enough (the maximal amplitude of the ECG is 1-2 mV, which is difficult to measure without electronic amplifiers) and also had a sufficiently high frequency response (much of the energy of an ECG is below 30-40 Hz, but higher frequencies are essential, and the current international ECG standard requires 150 Hz as upper frequency, while even 250 Hz is required for pediatric ECGs). At the turn of the 19th to 20th century, there was no instrument available with combined sufficient bandwidth and sufficient sensitivity to measure and record this type of signals.

The string galvanometer developed by Einthoven consisted of a thin silver-plated-quartz fiber to conduct the ECG current [1]. When placed in a magnet field, the fiber is displaced due to the force of the magnet field on the current. This is the same effect as is used in the electric motor. Since the heart beat current is very weak so is the displacement of the fiber. Therefore, the magnet field had to be very strong. Einthoven projected the shadow of the moving fiber on a running film sheet to record the signal and used an optical system to enhance its displacement considerably.

Fig. 2 Design drawing of the string galvanometer. In front the two poles of the electromagnet close to each other and the string in the narrow space in between. Also visible is the microscope assembly to record the string movement.


Einthoven had to overcome several obstacles in order his invention to be applied in medical practice. Initially he approached the German instrument maker Siemens & Halske. They answered him that the instrument didn’t fit into their production lines. Next Einthoven contacted two Dutch instrument making shops with the question to produce the equipment. However, the device was very bulky, heavy (some 600 lbs) and complicated to operate; five people were needed to make an electrocardiogram. The instrument makers convinced Einthoven that considerable effort was required to simplify the design and to make it market-ready. They had no time and money to do that job. Moreover, they estimated that only a small number of devices could be sold and no return on investment could be achieved. His following effort was more successful.


The Cambridge Scientific Instruments Company (CSI) was closely associated with the famous Trinity College. This company was a workshop for the development and supply of physiological instrumentation for the Cambridge scientific community. From the start, CSI showed an interest in manufacturing Einthoven’s string galvanometer. CSI could see the potential of the instrument but also realized that it had to be changed before it would sell. Before Einthoven and CSI came to a business agreement, legal difficulties appeared to put the agreement into jeopardy. At the same time as arranging a business deal with CSI in the United Kingdom, Einthoven was also negotiating an agreement with the firm of Max Edelmann in Germany. Edelmann’s physico-mechanical institute produced electrical measuring devices at the beginning of the 20th century and was located in Munich. Edelmann was very interested in manufacturing Einthoven’s apparatus. It was not long before Einthoven was caught up in the middle of competition between CSI and Edelmann. CSI was clearly trying to protect its English and American markets. But the company was threatened by Edelmann, who wanted access to the same markets. Edelmann was unwilling to leave the English and American markets to CSI. The matter was made more complicated by the fact that Einthoven did not own the patent rights to the instrument. He did not own these rights because there was no patent law in the Netherlands between 1869 and 1910. It is not clear why Einthoven did not claim the rights to the instrument in England and Germany. While Einthoven and CSI were building up a fruitful relationship, the association with Edelmann was taking a turn for the worse. After 1907, the agreement was cancelled unilaterally by Edelmann.


CSI improved the design and the first commercial instruments to be sold were marketed as physiological instruments. In 1905 a CSI instrument was sold to a physiological laboratory in Sheffield. The whole system was mounted on a table, so that it was easier to install. Actually, the string galvanometer might prove its worth in any job where small, rapidly alternating currents had to be recorded, and CSI wanted to reach a wider market than the physiological laboratories alone. A list of the first customers to buy the string galvanometer shows that the first models were not sold exclusively to physiologists or physiological institutions. The other organizations used it for telegraphic purposes. Although the string galvanometer was produced and found its way to customers, it was not until the further development of the field of cardiology that it became a predominantly medical instrument. Einthoven stayed in touch with the CSI Company until 1919 as an adviser.

Fig. 3 Finished string galvanometer. The long sides of the magnet are covered together by the windings of the tube for water cooling.

Having initially turned down Einthoven’s offer in 1902, Siemens renewed its interest in the instrument when the company read about Einthoven’s experiments in the Nord Deutsche Algemeine Zeitung. After Einthoven’s visit to Berlin the two parties discussed legal aspects. For Siemens legal protection for their innovations was a critical factor. Siemens wanted to know from Einthoven if he had any patents. However, by mid-1913 Siemens had two reasons for abandoning the string galvanometer for a second time. Being able to take out patents on Einthoven’s instrument was a cardinal point for them. Siemens published a new catalog for its medical instrument range in 1913 that included its own cardiograph, based on the so-called mirror galvanometer. Einthoven’s work on the development of the string galvanometer did merit a mention in the introduction to this catalog, but there was also reference to the drawbacks of the heavy and bulky design of his type of cardiograph. This first type of cardiograph marked the beginning of Siemens’s technological involvement in the field of cardiology.

What features set this work apart from similar achievements?

When Einthoven started his experiments, several others were involved in developing sensitive galvanometers to record the electrical signal of the heart. However, none of these approached the sensitivity and reliability of the string galvanometer.


Einthoven started to analyze the data resulting from the experiments performed with the Lipmann capillary electrometer, the Arsonval galvanometer and the Thomson galvanometer. This analysis led him to investigate the physical/mathematical characteristics of the instruments. Lipmann’s electrometer in particular held his attention. Not being a physicist, Einthoven had to overcome the problems of the mathematical equations. With the help of Nobel prize winner H. A. Lorentz (1853–1928), the famous Leiden professor of physics, he was able to solve the mathematical calculations that modeled the physical behavior of the mercury column. This mathematical approach provided him with a sound basis for the development of a new instrument, the string galvanometer. This instrument would combine the best of both worlds: the swiftness of the galvanometers and the sensitivity of the capillary electrometer.


Einthoven conducted clinical trials when he connected his laboratory with the academic hospital Leiden. The string galvanometer he had constructed was too heavy to be transported to the hospital. However, patients at the academic hospital were connected to the string galvanometer in Einthoven’s laboratory at about 1.5 km distance by means of a telephone line. Readable electrocardiograms were successfully taken. Based on these clinical recordings Einthoven characterized the shape of electrocardiograms as a number of successive “waves”, the in the time zones P, Q, R, S, and T and U waves, a convention which is still in use.

Fig. 4 Patient sitting in the university hospital while his telecardiogram is being taken in the physiological laboratory. The hands are immersed in a strong salt solution (NaCl) for good contact between the body and the telephone line.


In 1924, Einthoven was awarded the Nobel Prize in Physiology or Medicine "for his discovery of the mechanism of the electrocardiogram".

References to establish the dates, location, and importance of the achievement: Minimum of five (5), but as many as needed to support the milestone, such as patents, contemporary newspaper articles, journal articles, or citations to pages in scholarly books. You must supply the texts or excerpts themselves, not just the references. At least one of the references must be from a scholarly book or journal article.

Nota bene: In the days of Einthoven, the lingua franca of science was dynamically changing. This caused Einthoven to write his scientific papers in German, in French and later also in English. The non-English titles of the following reference list have all been translated into English [English titles between square brackets]. Papers in the English language have been marked by an *.


[1] Einthoven W., "Über die Form des menschlichen Elektrocardiogramms", [About the shape of the human electrocardiogram]. Pflüg Arch ges Physiol 60: 101-123, 1895.

[2] Einthoven W., "Beitrag zur theorie des Capillar-Elektrometers", [A contribution to the theory of the capillary electrometer]. Pflüg Arch ges Physiol 79: 1-25, 1900.

[3] Einthoven W., "Über das normale menschliche Elektrocardiogramm und über die capillär-elektrometrische Untersuchung einiger Herzkranken", [About the normal human electrocardiogram and about investigating some cardiac patients with the capillary electrometer (with K. de Lint)]. Pflüg Arch ges Physiol 80: 139-160, 1900.

[4] Einthoven W., "Un nouveau galvanomètre", [A novel galvanometer]. Arch néerl des Sciences Exact Nat serie 2 vol 6: 625-633, 1901.

[5] Rosenstein S.S., "Galvanometrische registratie van het menschelijk electrocardiogram", [Galvanometric registration of the human electrocardiogram]. In: Remembrance Volume, pp. 101-106, Eduard IJdo, Leiden, The Netherlands, 1902.

[6] Einthoven W., "Die galvanometrische Registerung des menschlichen Elektrokardiogram: Zugleich eine Beurteilung der Anwendung des Capillär-Elektrometers in der Physiologie", [Galvanometric recording of the human electrocardiogram: at the same time an evaluation of the use of the capillary electrometer in physiology]. Pflüg Arch ges Physiol 99: 472–480, 1903.

[7] Einthoven W., "Le télécardiogramme", [The telecardiogram]. Arch Int Physiol 4: 132-164, 1906

[8*] Mathewson F.A.L. and Jackh H., "The telecardiogram", [Translation of selected paragraphs from Einthoven W., "Le télécardiogramme". Arch Int Physiol 4: 132-164, 1906]. Am Heart J 49: 77-82, 1955.

[9*] Blackburn H.W., "The telecardiogram", [Translation, starting at paragraph 35, from Einthoven W., "Le télécardiogramme". Arch Int Physiol 4: 132-164, 1906]. Am Heart J 53: 602-615, 1957.

[10] Einthoven W., "Weiteres über das Elektrokardiogramm"; nach gemeinschaftlich mit Dr. B. Vaandrager angestellten Versuchen mitgeteilt [More about the electrocardiogram; communicated after research in cooperation with Dr. B. Vaandrager]. Pflüg Arch ges Physiol 122: 517-584, 1908.

[11] Einthoven W., "Die Konstruktion des Saitengalvanometers", [Construction of the string galvanometer]. Pflüg Arch ges Physiol 130: 287-321, 1909.

[12] Einthoven W., "Über die Deutung des Elektrokardiogramms", [About the interpretation of the electrocardiogram]. Pflüg Arch ges Physiol 149: 65-86, 1912.

[13] Einthoven W., Fahr G. and De Waart A., "Über die Richtung und die manifeste Grosse der Potentialschwankungen im menschlichen Herzen und uber den Einfluss der Herzlage auf die Form des Elektrokardiogramms", [On the direction and manifest size of the variations of the potentials in the human heart and on the influence of the position of the heart on the form of the electrocardiogram]. Pflugers Arch ges Physiol 150: 275-315, 1913.

[14*] Hoff H.E. and Sekelj P., "On the direction and manifest size of the variations of potential in the human heart and on the influence of the position of the heart on the form of the electrocardiogram", [Translation of Einthoven W., Fahr G. and De Waart A., "Über die Richtung und die manifeste Grosse der Potentialschwankungen im menschlichen Herzen und uber den Einfluss der Herzlage auf die Form des Elektrokardiogramms", Pflugers Arch ges Physiol 150: 275-315, 1913]. Am Heart J 40: 163-211, 1950

[15*] Einthoven W., "The string galvanometer and the measurement of the action currents of the heart", (Nobel Lecture, December 11, 1925). In: Nobel Lectures, Physiology or Medicine 1922-1941, Elsevier Publishing Company, Amsterdam, 1965

[16*] Lewis T. "Willem Einthoven, MD, PhD", (Obituary). Br Med J 2(3483): 664-665, 1927

[17*] Snellen H.A., "Willem Einthoven, Father of electrocardiography". Kluwer Academic Publishers, Dordrecht, The Netherlands, 1995.

[18*] Dijk J, and Van Loon, B., "The electrocardiogram centennial: Willem Einthoven (1860-1927)". Proc IEEE 94: 2182-2185, 2006

Supporting materials (supported formats: GIF, JPEG, PNG, PDF, DOC): All supporting materials must be in English, or if not in English, accompanied by an English translation. You must supply the texts or excerpts themselves, not just the references. For documents that are copyright-encumbered, or which you do not have rights to post, email the documents themselves to ieee-history@ieee.org. Please see the Milestone Program Guidelines for more information.

[1] Media:Einthoven-1895_Article_UeberDieFormDesMenschlichenEle.pdf

[2] Media:Einthoven-1900_Beitrag_zur_theorie_des_Capillar-Elektrometers_1900.pdf

[3] Media:Einthoven-1900-Über_das_normale_menschliche_Elektrocardiogramm.pdf

[4] Media:Einthoven-1902_Un_nouveau_galvanomètre_1901.pdf

[5] Media:Einthoven-1902_Boek-Rosenstein.pdf

[6] Media:Einthoven-1903_Die_galvanometrische_Registerung_des_menschlichen_Elektrokardiogram.pdf

[7] Media:Einthoven-1906_Le_Telecardiogramme_nw_scan.pdf

[8] Media:Mathewson-1955_Translation_Einthoven-1906_TheTelecardiogram_AmHeartJ_(translation).pdf

[9] Media:Blackburn-1957_Translation_Einthoven-1906_TheTelecardiogram_(translation)_AmHeartJ_apr1957.pdf

[10] Media:Einthoven-1908_Weiteres_über_das_Elektrokardiogramm.pdf

[11] Media:Einthoven-1909_Die_konstruktion_des_seitengalvanometer_scanned_600dpi.pdf

[12] Media:Einthoven-1912_Über_die_Deutung_des_Elektrokardiogramms.pdf

[13] Media:Einthoven-1913_UberDieRichtung_1913.pdf

[14] Media:Hoff-1950_Translation_Einthoven-1913_On_the_direction_(translation_by_Hoff)_AmHeartJ_Aug1950.pdf

[15] Media:Einthoven-1925_Nobel-lecture.pdf

[16] Media:Lewis-1927_Willem_Einthoven_MD_PhD_Obituary_BritishMedJ_Oct8_1927.pdf

[17] Media:Snellen-1995_Book_WillemEinthoven18601927Father.pdf

[18] Media:ScanOurPast2006+Einthoven.pdf

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