The Anode and the Sunrise Every chemist and physicist connects the phenomenon of electrolysis with the great English self-taught scientist Michael Faraday. It is he who has given us the laws of electmlysis a s well as the terms describing the phenomena involved. Faradav was venr careful in chwsina - new scientific terms. havoid false assmiation with the meanings i n common parlance he prefemd to derive them from dead, ancient languages. As he knew no Greek he ean~ultedhis friends Dr. Whitlack NlLhols and the Rev. Robert W~llisH e called also for aid of the Rex Wdliam Whewell of h n i t y Collrge, Cnmhndge ( 1 , .A h r some earrespondencr with Rev Whewrll. Varaday accepted new terms, which fin hls theory. According to Faraday's views, when two endings of the electrostatic machine or of the Voltaic pile were dipped into electrolyte solution, the electric current entered mto the solution through one ofthem and left it through the other. Each of thrse endings was thus the way uf electricity, and, rmce in Greek "way" is &n, Faxaday named lhcse ends "electrde" (2). Faradafs study of electrical decomposition of substances followed immediately after his study on electromagnetism. The following passage of his lecture read in 1833 and 1834 is thus easily understood (3). (The parts of phrases in parenthesis are written a s notes a t the bottom of the page in the original.) Wishing for a neutral standard of electric direction to which I might refer these, expressive of their difference and a t the same time free from all theory, I have thought i t might be found in the earth. If the magnetism of the earth he due to electric currents passing round it, the latter must be in constant direction, which according to present usage of speech, would be from east to west, which will strengthen this help to memory, that i n which sun appears to move. If in any case of electmdecomposition we consider the decomposing hody as placed so that the current passing it shall be in the same direction, and parallel to that supposed to exist i n the earth, then the surfaces a t which the electricity is passing into and out of the substance would have invariable reference and exhibit constantly the same relation of powers. Upon this notion we purpose calling that towards the east anode Lava upwards downwards and 0% away; the and 0605 away; the way which the sun rises] and that toward the west cathode [qa~a way the sun sets]." , as "ion", (the wanderer), "anion" (an ion wandering towards a n anode) and Many terms introduced by F a r a d a ~such "cation" (an ion wandering towards cathode) (4) are used generaUy i n modern science. I t should be noted that Faraday in his~lecture "the electrical deeomoosition" of substances and never used the term. "electmlvsis". This .... ~ . sooke r about ~ ~ ~ ~ term, a n analogy to rhrmieal decompoaition-analysis was formed in later yrars. It is, however. ~stnruvhingthorin no tenbook leven in the I'artingtnn's p e a t Hisloryo/Chemirtrj, nor in no popular publication can the etymology of the terms -anodr" and "cathode" I w found. This information would add color to rwry lecture and text. ~
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Literature Cited 1. Wll~anw.L. P MtchdFomdny. Plenum New York. 1965. pp 25WkR.Thomar.J H.(%pmlatr) m X D o m 1S81.27l8.765 2. Farads). 31. h ' x p n m n a l Rxearchea m Elrrrnr,n. lmndnn, lh38.. 9 662 J ~ ~ ~ , . d ~ y . ~ . ~ ~ p efi.rarrhsr n r n p n m ~~ l e m m y ~. a n d . m .1 0 8 , . E 661 4 I'AT..~.,. M E l r p n m n m l & h w n - h r x mF - r l r r o o . London. I618. 5 565
Roman Mierreckl University of Warsaw Warsaw, Poland
Volume 69 Number 8 August 1992
657
