(This is my entry to the first “special edition” of The Giant’s Shoulders, dubbed “The Leviathan’s Shoulders”, with an emphasis on oceans and ocean life. The post is actually about a river creature, but, hey, it’s still aquatic!)
I’ve spent a lot of time talking about Michael Faraday (1791-1867) and his scientific accomplishments on this blog. His thorough investigations into the nature of electricity and magnetism paved the way for all of modern electromagnetics as well as optics, and he is rightly viewed as one of the greatest experimentalists of all time. Among his monumental works are the observation that changing magnetic fields induce electric fields (electromagnetic induction) and the observation that light polarization can be affected by an applied magnetic field (Faraday rotation).
Though it is natural to think of Faraday as a researcher of electricity alone, in his era the study of electricity connected to almost every aspect of the natural sciences. In the late 1700s Luigi Galvani had shown that an amputated frog’s leg could be made to move by electrical stimulation, demonstrating a connection between biological function and electricity. By 1800 it was known that chemical reactions can be induced by electricity, in a process known as electrolysis; Faraday himself published fundamental results on electrolysis in 1834. Electricity could be connected to thermodynamics through the observation that an electrical current heats the wire it passes through (Joule heating); this process was rather mysterious because neither the origins of heat (atomic motion) nor electricity (electrons) were established in Faraday’s time.
Electricity could be generated through atmospheric, chemical, and mechanical means, and it was by no means obvious that these different sources were manifestations of the same fundamental electrical phenomenon. (In fact, Faraday himself did a significant amount of research to demonstrate that all forms of electricity are in fact the same. )
A researcher of electricity could therefore be expected to make forays into quite diverse areas of study. In 1839, Faraday published the scientific results of one of his forays, “Notice of the character and direction of the electric force of the Gymnotus,” in the Philosophical Transactions of the Royal Society (pp. 1-12).
What is the “Gymnotus”? The taxonomy of the species seems to have been changed over the years, but at this time seems to be referring to what used to be known as Gymnotus electricus, or the electric eel (image source):
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Skulls in the Stars 