provided the basis for much of our present day technology.1
1 There is an interesting aside to Oersted's career. In 1801 after finishing his training as a
physicist, he traveled throughout Europe visiting other scientists. For several weeks he
stayed with Carl Ritter, a prominent physicist in Jena. Ritter had discovered the existence of
ultraviolet light, invisible to the eye, and was very much interested in the Galvani-Volta
controversy. he was the eccentric genius type, given to both sound experiment and wild
speculation. After Oersted left, the two continued to correspond, and in May 1803 Ritter
wrote to Oersted that in the years in the which earth's plane of the ecliptic was maximally
inclined, major discoveries were made in the science of electricity. He predicted that
another major discovery would be made in 1819-1820---it was, by Oersted himself.
The controversy over "animal electricity" continued unabated even though most of the original
protagonists had retired from the scene. A major technological discovery did much to both clarify and
to cloud the issue. Working from Oersted's discovery, Nobeli, professor of physics at Florence invented
the static galvanometer, which was capable of sensing extremely small currents. In the 1830's Carlo
Matteucci, professor of physics at Pisa, began a series of experiments that were to continue until his
death in 1865. His primary interest was in the "animal electricity" demonstrated by Galvani in his
second series of experiments not involving contact with metals. Using Nobeli's galvanometer Matteucci
was able to prove beyond a doubt that an electrical current was generated by injured tissues and that in
fact, serial stacking of such tissue could multiply the current in the same fashion as adding more
bimetallic elements to a Voltaic pile. The current was continuously flowing--a direct current-- and the
existence of at least this type of "animal electricity" was finally and unequivocally proven. However, it
was not located within the central nervous system per se and seemed to have little relationship to the
long sought "vital force."
Matteucci published many of his observations in a book in 1847 which came to the attention of
Johannes Müller, then the foremost physiologist in the world and professor at the medical school in
Berlin. Müller had been of the opinion that while electricity could stimulate a nerve, it was not
involved in its normal function in any manner, and he continued to embrace the vitalistic doctrine of a
mysterious "vital force." When he obtained a copy of Matteucci's book he gave it to one of his best
students, Du Bois-Reymond, with the suggestion that he attempt to duplicate Matteucci's experiments.
Du Bois-Reymond was a skilled technical experimenter and within a year he had not only duplicated
Matteucci's experiments. but had extended them in a most important fashion. he discovered that when a
nerve was stimulated an electrically-measurable impulse was produced at the site of stimulation and
then traveled at high speed down the nerve producing the muscular contraction. Du Bois-Reymond had
discovered the nerve impulse, the basic mechanism of information transfer in the nervous system. he
was not unaware of the importance of his discovery, writing, " I have succeeded in realizing in full
actuality (albeit under a slightly different aspect) the hundred years dream of physicists an
physiologists."
This great contribution was tarnished somewhat by Du Bois-Reymond's intemperate and
uncalled for attacks upon Matteucci. In fact he seemed to be of a particularly argumentative nature for
he shortly became embroiled in a bitter dispute with one of his own students--Hermann--over the
resting potential. The resting potential was a steady voltage that could be observed on unstimulated
nerve or muscle. Hermann believed that all resting potentials were due to the injury currents of
Matteucci and that without injury there would be no measurable potential. Du Bois-Reymond was
ELECTROMAGNETISM & LIFE - 15