A Century-Old Experiment Still Relevant Today

RH 1918 rev

Prof. Rudolf Höber, Kiel, around the time he published his article on measuring electric current inside cells.


There are about 75 million cells in a tablespoon of blood.  My grandfather, Rudolf Höber, an early cellular physiologist, spent his whole life studying these microscopic entities, trying to figure out how they work.  He and others knew that electric current is conducted within and between these cells.  How much electric current?  How does it work? How do you measure it?  My grandfather figured it out.  He published the method of measuring conductivity in cells in a German scientific journal, Pflüger’s Archiv für die gesamte Physiologie der Menschen und der Tiere [“Journal of General Physiology of Humans and Animals.”]  In the original, it looked like this:

Rudolf Höber’s article on measuring electrical current inside blood cells, as it originally appeared in “Pflügers Archiv” in 1910.

Apparatus diagrams as published in “Pflügers Archiv” in 1910.

A couple of years ago, I was surprised to learn that my grandfather’s work on the measurement of electrical current in cells was still considered relevant, sufficiently so that it warranted publication of its own commemorative article.  Ron Pethig, Professor of Bioelectronics and Dr. Ilke Schmueser, Researcher, both at the University of Edinburgh, published “Marking 100 Years Since Rudolf Höber’s Discovery of the Insulating Envelope Surrounding Cells and of the Beta-Dispersion Exhibited by Tissue” (Journal of Electrical Bioimpedence, vol. 3, pp. 74-49, 2012).


Recently, I was unexpectedly contacted by James C. M. Hwang, a senior research professor in materials science at Cornell University.  He had just completed an article on “Label-free Noninvasive Cell Characterization by Broadband Impedance Spectroscopy, to be published next year by the Institute of Electrical and Electronic Engineers in its IEEE Microwave Magazine .  His article reviews work done by various scientists in the past, including that of my grandfather, and finds that the principles they explored may be adapted to promise advances in science and engineering using today’s technologies.  He found the work of my grandfather sufficiently interesting and relevant today that he enlisted a German-native-speaker colleague, Prof. Dieter G. Ast, to collaborate with him on producing an English translation.  And now I am very pleased to be able to present “A Method to Measure the Electrical Conductivity Inside Cells,” available for the first time in English, thanks to Profs.  Hwang and Ast.  In the continuing documentation of our family’s history, we are grateful to them for this work. The complete translation appears at the end of this post.


I have been told that  my Opa Rudi, the great physiologist, had hopes that I might follow him into a career in the sciences.  Alas, my life took me in different directions.  As a result, I must admit that my understanding of my grandfather’s groundbreaking article is limited, even in English.  Nevertheless, it is a great satisfaction that scientists who do have the necessary knowledge find his work of a century ago to be relevant for further research, discovery and invention in the twenty-first century.

NOTE: The copyright on my grandfather’s original article is arguably still owned by the successor to the original publisher.  Hence the following notice:  Translated by permission of Springer Nature, Rudolf Höber,  Pflüger’s Archiv für die gesamte Physiologie der Menschen und der Tiere, “Eine Methode, die Leitfähigkeit im Innern von Zellen zu messen,” copyright 1910.

Hwang 1 (3)

Hwang 2(3)

Hwang 3(3)

Hwang 4(3)

Hwang 5(3)

Hwang 6(3)

Hwang 7(3)