The Great Seal of California bearing the word eureka, referring to the discovery of gold there in 1848. A round seal depicting the goddess Athena/Minerva, a grizzly bear, ships sailing into San Francisco Bay, and a miner digging for gold.
8 August 2022
Eureka is a cry made upon discovering something or coming to a sudden realization. It is from the Greek εὕρηκα (I have found it).
Vitruvius (c.75–15 BCE), in his De archtectura, says that the cry originated with the mathematician Archimedes (c.287–c.212 BCE). King Heiro II of Syracuse had donated an amount of gold to be made into a votive crown for one of the temples in the city, but Hiero wanted to be sure the finished crown had not been adulterated by replacing some of the gold with silver. With the mathematics of the day incapable of calculating the volume of an irregularly shaped object like the crown, Archimedes puzzled over how to measure its volume. Then one day when in the bath, so the story goes, Archimedes realized that that he could indirectly measure the volume of the crown by measuring the amount of water it displaced when submerged. He supposedly leaped out of the bath and ran naked through the streets of Syracuse shouting, “Eureka! Eureka!” The crown, it turns out, had indeed been adulterated with silver.
The incident probably never occurred, at least not this way and especially not this dramatically. Archimedes makes no mention of it in any of his surviving works. And just as the mathematics of the day was not capable of calculating the volume of the crown, the precision required to measure the difference in water displacement between gold and silver was also not possible in Archimedes’s day. But Archimedes does outline the principle of a hydrostatic balance in his work On Floating Bodies, and he may have used such a balance to make the determination. But the bit about running through the streets naked and screaming is almost certainly mythical.
Still, a story need not be true to inspire a word’s use. And Vitruvius, and the others who repeated the tale, were widely read over the ensuing centuries. References to the tale and Archimedes’s alleged cry of Eureka! start appearing in English by the sixteenth century. A preface, written by John Dee, proto-scientist and mystic, to a 1570 translation of Euclid’s Geometry contains the following lines:
For this, may I (with ioy) say, EYPHKA, EYPHKA, EYPHKA: thanking the holy and glorious Trinity: hauing greater cause therto, then Archimedes had (for finding the fraude vsed in the Kinges Crowne, of Gold).
But Dee is using the Greek alphabet. We see it in Latin letters, with the spelling heureca, in Philemon Holland’s 1603 translation of Plutarch’s Morals:
As for Archimedes, he was so intentive and busie in drawing his Geometricall figures, that his servants were faine by force to pull him away to be washed and anointed; and even then he would from the strigil or bathcombe (which served to currie and rub his skin) draw figures even upon his very bellie: and one day above the rest, having found out whiles he was bathing, the way to know, how much golde the gold-smith had robbed in the fashion of that crowne which king Hiero had put forth to making, he ran foorth suddenly out the baine, as if he had beene frantike, or inspired with some fanaticall spirit, crying out; Heureca, Heureca, that is to say, I have found it, I have found it, iterating the same many times all the way as he went.
And by the mid eighteenth century, eureka was being used in English writing with the present-day spelling and without explicit allusion to Archimedes. The various editions of Henry Fielding’s satirical novel Joseph Andrews show the word in transition and anglicization. A passage from the 1742 second edition of the novel reads as follows:
They stood silent some few Minutes, staring at each other, when Adams whipt out on his Toes, and asked the Hostess “if there was no Clergyman in that Parish?” She answered, “there was.” “Is he wealthy?” replied he; to which she likewise answered in the Affirmative. Adams then snapping his Fingers returned overjoyed to his Companions, crying out, “Eureka, Eureka;” which not being understood, he told them in plain English “they give themselves no trouble; for he had a Brother in the Parish who would defray the Reckoning, and that he would just step to his House and fetch the Money, and return to them instantly.
The first edition, printed a earlier in 1742, uses the Greek letters, reading Ευρηκα, Ευρηκα. And the 1743 third edition reads, Heureka, Heureka. At this point, the word had not yet standardized or become fully anglicized, rapidly moving from being printed in Greek letters to different spellings in the Latin alphabet. Since then, the eureka spelling has become the standard, and heureka fell by the wayside.
Some claim that Eureka! is the greatest word in the history of science, but others have pointed out that most scientific discoveries are not heralded by Eureka! but rather by that’s weird.
Sources:
Dee, John. Elements of Geometrie (preface). H. Billingsley, trans. London: John Daye, 1570, sig. c.ii.v. Early English Books Online (EEBO).
Fielding, Henry. The History of the Adventures of Joseph Andrews, vol.1 of 2. A. Millar, 1742, 266. Eighteenth Century Collections Online (ECCO).
———. The History of the Adventures of Joseph Andrews, second edition, vol.1 of 2. London: A. Millar, 1742, 267. Eighteenth Century Collections Online (ECCO).
———. The History of the Adventures of Joseph Andrews, third edition, vol.1 of 2. A. Millar, 1743, 266. Eighteenth Century Collections Online (ECCO).
Oxford English Dictionary, second edition, 1989, s.v. Eureka, int. (and n.).
Plutarch. The Philosophie Commonlie Called, the Morals. Philemon Holland, trans. London: Arnold Hatfield, 1603, 590. Early English Books Online (EEBO).
Image credit: State of California, 1937. Public domain image as the copyright was not renewed.