holt

Photo of a red, British phone box alongside a wooded, country road

Phone box in Holt Forest, Dorset, England

23 October 2024

Holt, a word for a wooded area, a copse, goes back to Old English. Its root is common Germanic, with cognates found in Old Norse, Old Frisian, Old Saxon, Old High German, and others.

The word appears in Beowulf when the hero’s men abandon him when faced with the dragon:

Nealles him on heape    handgesteallan,
æðelinga bearn     ymbe gestodon
hildecystum,    ac hy on holt bugon,
ealdre burgan.

(His companions in the company, sons of nobles, did not at all stand by him valorously, by they fled into the holt to save their lives.)

But perhaps the most famous appearance of the word is in opening lines of General Prologue to Chaucer’s Canterbury Tales and its description of spring:

Whan that Aprill with his shoures soote
The droghte of March hath perced to the roote,
And bathed every veyne in swich licour
Of which vertu engendred is the flour;
Whan Zephirus eek with his sweete breeth
Inspired hath in every holt and heeth
Tendre croppes, and the yonge sonne
Hath in the Ram his half cours yronne,
And smale foweles maken melodye,
That slepen al the nyght with open ye
—So priketh hem Nature in hir corages—
Thanne longen folk to goon on pilgrimages,
And palmeres for to seken straunge strondes,
To ferne halwes, kowthe in sondry londes;
And specially from every shires ende
Of Engelond to Caunterbury they wende,
The hooly blisful martir for to seke,
That hem hath holpen whan that they were seeke.

(When April with its showers sweet
The drought of March has pierced to the root,
And bathed every vein in such liquid
By which is engendered the vitality of the flower;
When Zephyr also with his sweet breath
Has in every holt and heath breathed life into
Tender buds, and the young Sun
Has in Aries run half its course,
And small birds make melodies,
Those that sleep all the night with open eyes
—So Nature goads them in their hearts—
Then folk long to go on pilgrimages,
And pilgrims to seek foreign shores,
To distant shrines, known in sundry lands;
And especially from every shire’s end
Of England to Canterbury they go,
To seek the holy blessed martyr,
Who helped them when they were sick.)

In the modern period, holt developed another sense, that of a wooded hill. This probably developed from poetic descriptions of copses in highland regions. For instance, we see this use of highest holts in a poem by George Turberville published in 1567:

What Tongue can tell the wo?
what Pen expresse the plaint?
Vnlesse the Muses helpe at néede
I féele my wits to faint.
Yée that frequent the hilles
and highest Holtes of all,
Assist mée with your skilfull Quilles
and listen when I call.

But another of Turberville’s poems in the same collection uses holt in the sense of a wooded area, so when he wrote highest holts, the holt isn’t a hill, but a woods on a high hill:

For water slipped by
may not be callde againe:
And to reuoke forepassed howres
were labour lost in vaine.
Take time whilst time applies
with nimble foote it goes:
Nor to compare with passed Prime
thy after age suppoes.
The holtes that now are hoare,
both bud and bloume I sawe.

And by the mid-eighteenth century, the sense of holt as the hill itself was clearly established, as we can see from John Dyer’s use of craggy holt in his 1757 poem The Fleece:

High Cotswold also ’mong the shepherd swains
Is oft remember’d, though the greedy plough
Preys on its carpet: He, whose rustic muse
O’er heath and craggy holt her wing display’d,
And sung the bosky bourns of Alfred’s shires,
Has favour’d Cotswold with luxuriant praise.

It's worth noting, however, that in Old Icelandic holt meant both a woods and a stony hill or ridge. Iceland isn’t known for its trees, and it seems likely that the word changed in this language because there wasn’t much call for words meaning a wooded area. It is most likely that this parallel semantic development is unconnected to the one in English, but the possibility of an Icelandic influence on English usage cannot be completely discounted.

There is another holt, spelled and pronounced the same but with an entirely different meaning and origin. It is a variant of hold, meaning a fortress or refuge, as in stronghold, but referring to an animal’s den, particularly the den of an otter. This sense dates to the late sixteenth century. From Thomas Cockaine’s 1591 A Short Treatise on Hunting:

An Otter sometimes will be trayled a mile or two before he come to the holt where he lyeth, and the earnestness of the sporte beginneth not till he be found, at which time some must runne up the water, some downe to see where he beats, and so pursue him with great earnestness till bee he kild.

(The use of beat here is in a hunting sense meaning to attempt to escape, especially along a stream or river.)

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Sources:

Chaucer, Geoffrey. “General Prologue.” The Canterbury Tales, lines 1.1–18. Harvard’s Geoffrey Chaucer Website.

Dictionary of Old English: A to Le, 2024, s.v. holt, n.

Dyer, John. The Fleece: A Poem in Four Books. London: R. and J. Dodsley, 1757, lines 2.381–86, 65.

Fulk, R. D., Robert E. Bjork, and John D. Niles. Klaeber’s Beowulf, fourth edition, Toronto: Toronto UP, 2008, lines 2596–99a, 89.

Middle English Dictionary, 2019, s.v. holt, n.

Oxford English Dictionary, second edition, 1989, s.v. holt, n.1.

Turberville, George. Epitaphes, Epigrams, Songs and Sonets. London: Henry Denham, 1567, 56, 33. ProQuest: Early English Books Online.

Zoëga, Geir. A Concise Dictionary of Old Icelandic (1910), University of Toronto Press, 2004, s.v. holt, n.

Photo credit: Toby, 2006. Wikimedia Commons. Licensed under a Creative Commons Attribution-Share Alike 2.0 Generic license.

thorium

Oil on canvas painting of Thor on his goat-driven chariot and wielding his hammer against giants

Tors strid med jättarna (Thor's Fight with the Giants), Mårten Eskil Winge, 1872

18 October 2024

Thorium is a chemical element with atomic number 90 and the symbol Th. It is named after the Norse god Thor + -ium. It is a soft, malleable, silver-colored metal. All the isotopes of thorium are radioactive, but the most stable one, 232Th, has a half-life of over 14 billion years, or equal to the age of the universe. Thorium has some uses in scientific instruments, high-end optics, gas mantles, and vacuum tubes, but these uses are dwindling. It has been suggested as a possible fuel for nuclear reactors, and a few experimental reactors using the element as fuel have been constructed.

In 1815 chemist Jöns Jacob Berzelius announced what he thought to be a new element, and three years later he dubbed it thorjord (thor’s earth; thorina in French), after the ancient Norse god Thor. But Berzelius was mistaken, and the mineral was actually a compound of yttrium. The chemist retracted his discovery in 1824. But in 1829, Berzelius identified the element in a different ore, which had been found and given to him by amateur minerologist Morten Thrane Esmark, and he recycled the earlier name:

Detta mineral innehåller en förut obekant metallisk kropp, hvilken, i afseende till sina egenskaper hörer till dem, som bilda de så kallade egentliga jordarterna, och dess oxid är en jord, som närmast liknar zirkonjorden och som, bysynnerligt nog, har största delen af de egenskarper och kännetecken, dem jag i min äldre beskrifning af thorjorden has denna funnit. Denna omständighet föranledde mig att, i början af denna undersökning, fästa namnet thorjord vid den nya jorden; och ehuru jag, vid en förnyad undersökning af hvad some ännu âterstod af det mineral, i hvilket jag trott mig finna den äldre thorjorden, icke kunde upptäcka det minsta spår af den nya sâ har jag dock trott mig med så mycket större skäl kunna för den sistnämda behålla samma namn, som den äldre beskrifningen till det mesta passar derpå, och detta namn en gång är i vetenskapen infödt. Detta medförer en gifven grund för det nya mineral, som jag kallar Thorit.

(This mineral contains a previously unknown metallic body, which, in regard to its properties, belongs to those which form the so-called proper earths, and its oxide is an earth which most closely resembles zircon ore, and which, curiously enough, has the greater part of the characteristic features and characteristics, those I have found in my older description of thorjorden. This circumstance induced me, at the beginning of this investigation, to attach the name thorjord to the new earth; and although, on a renewed examination of what still remained of the mineral in which I thought I found the older thor soil, I could not discover the smallest trace of the new one, yet I have believed myself with much greater reason to be able for the latter retain the same name, as the older description mostly fits it, and this name is once native to science. This provides a given basis for the new mineral, which I call Thorite.)

In early English use, the element was called the element thorina or thorinum, after the French name thorina, but these names had gone out of use by the late nineteenth century, and the form thorium was universally adopted.

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Sources:

Berzelius, Jöns Jacob. “Undersökning af ett nytt mineral, som innehåller en förut obekant jord” (1829). Kungl. Svenska vetenskapsakademiens handlingar. Stockholm: P. A. Norstedt & Söner, 1830,1–30 at 2–3. Biodiversity Heritage Library.

Miśkowiec, Pawel. “Name Game: The Naming History of the Chemical Elements: Part 2—Turbulent Nineteenth Century.” Foundations of Chemistry, 8 December 2022. DOI: 10.1007/s10698-022-09451-w.

Oxford English Dictionary, second edition, 1989, s.v. thorium, n., thorina, n., thorinum, n.

Image credit: Mårten Eskil Winge, 1872. Nationalmuseum Sweden. Wikimedia Commons. Public domain image.

heaven / seventh heaven

Portion of an Old English homily that refers to the seventh heaven, Cambridge, Corpus Christi College, MS 162, 384

16 October 2024

The word heaven can be traced to the Proto-Germanic root *hemina- / *hemna-. That root gives us the Old English heofon, which is cognate with the Old Saxon heƀan, the Old Icelandic himinn, and the Old High German himil, among others. Going further back, the exact connection to Proto-Indo-European is muddy and uncertain, but it may be from a root something like *ke-men.

The basic meanings of the word that we still use today were mostly present in Old English. The use of heaven to mean the sky or firmament in which the celestial objects move can be seen in Beowulf, line 1571, when Beowulf first sees the sword that he will use to kill Grendel’s mother; the light shining from the sword is compared to the sun in the sky:

Lixte se leoma,    leoht inne stod,
efne swa of hefene    hadre scineð
rodores candel.

(The radiance gleamed, the light stood within, as from heaven, the sky’s candle clearly shines)

That’s heaven in the singular, but the use of the plural to mean the same thing can be seen in an Old English gloss on Psalm 8 found in the Vespasian Psalter. The Latin psalter was copied in the second quarter of the eighth century, and the Old English gloss added in the early ninth:

for ðon ic gesie heofenas werc fingra ðinra monan & steorran ða ðu gesteaðulades.

quoniam uidebo caelos opera digitorum tuorum, lunam et stellas quas tu fundasti

(for I see the heavens, the work of your fingers, the moon and the stars which you have created)

We see heaven used to mean the abode of God in Cynewulf’s poem Elene. Elene, or Helena, was the mother of Emperor Constantine, who led a pilgrimage to the Holy Land to find the True Cross:

                       Sie þara manna gehwam
behliden helle duru,    heofones ontyned,
ece geopenad    engla rice,
dream unhwilen,    ond hira dæl scired
mid Marian,    þe on gemynd nime
þære deorestan    dæg-weorðunga
rode under roderum,    þa se ricesða
ealles ofer-wealdend     earme beþeahte.

(For every one of those who commemorate the feast-day of most beloved cross under the skies that the mightiest Overlord took into his arms may the door of hell be closed, the heavens revealed, the kingdom of angels eternally opened, joy everlasting, and their part decreed by Mary.)

In Old English, heaven could also be used to refer to the abode of non-Christian gods. We see this in the translation of Boethius’s Consolation of Philosophy, which dates to the late ninth century:

ðu geherdest oft reccan on ealdum leasum spellum þætte Iob Saturnes sunu sceolde beon se hehsta god ofer ealle oðre godas, and he scelde bion þæs heofenes sunu and scolde ricsian on heofenu.

(You have often heard tell in old false stories that Jove, the son of Saturn, was supposed to be the highest god over all the other gods, and he was supposed to be the son of heaven and supposed to rule in the heavens.)

The phrase seventh heaven, or more accurately seofoðan heofon, also dates to Old English. Heaven, according to the Talmud, is divided into seven parts, with the seventh being the abode of God. The idea of seven probably arises out of a connection with the seven “planets” of the ancients (Mercury, Venus, Mars, Jupiter, Saturn, the moon, and the sun; cf. planet). This idea carried over into Islam and is referred to in the Qur’an and in the Hadith, as well as into Christian tradition, although the concept doesn’t appear in the Christian Bible. We can see this Old English use of seventh heaven in an early eleventh-century homily for Easter Sunday:

Ærest, æt fruman, he geworhte heofonas & eorðan, sunnan & monan, & ealle gesceafta, & þa seofon heofonas mid nigon engla endebyrdnyssum. Þone seofoðan heofon he geworhte him sylfum on to sittenne. Þ[æt] is þonne þære halgan þrynnysse heofon.on þam sit se ælmihtiga God, se ðe þone man of eorðan slime geworhte.

(First, at the beginning, he created the heavens & the earth, the sun & the moon, & all creation, & the seven heavens with nine orders of agnels. The seventh heaven he created for himself to abide in. That is therefore the heaven of holy Trinity in which abides the almighty God, he who created man from earthly slime.)

But extended uses of heaven come somewhat later. The use to mean a state of bliss dates to the Middle English period, and we see that sense in Chaucer’s Troilus and Criseyde:

This yard was large, and rayled alle th’aleyes,
And shadewed wel with blosmy bowes grene,
And benched newe, and sonded alle the weyes,
In which she walketh arm in arm bitwene,
Til at the laste Antigone the shene
Gan on a Troian song to singen cleere,
That it an heven was hire vois to here.

(The garden was large, and all the paths fenced and well shaded with blossomy green boughs, and newly provided with benches, and all the paths sanded, in which walked arm in arm between, till at last Antigone the bright began to sing a Trojan song clearly, so that it was a heaven to hear her voice.)

And we see seventh heaven used to mean a state of bliss by the late eighteenth century. Here is an example from a 1786 anecdote about the late writer Henry Fielding:

The invitation was accepted—the viands were spread—the exhilarating juice appeared—and cares were given to the winds. The moments flew joyous, and unperceived; they both partook largely of “the feast of reason, and the flow of soul.” In the course of their tête-à-tête, Fielding became acquainted with the state of his friend’s pocket. He emptied his own into it; and parted, a few periods before Aurora’s appearance, greater and happier than a monarch. Arrived at home, his sister, who waited his coming with the greatest anxiety, began to question him as to his cause for staying. Harry began to relate the felicitous rencontre—his sister Amelia tells him, the Collector had called for the taxes twice that day. This information let our worthy author down to earth again, after his elevation, in his own reflections, to the seventh heaven. His reply was laconic, but memorable: “Friendship has called for the money, and had it:—let the Collector call again.”

Nothing can bring one down to earth faster than a visit from the tax man.

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Sources:

American Heritage Dictionary Indo-European Roots Appendix, 2022, s.v. ak-.

Boethius. The Old English Boethius, vol. 1 of 2. Malcolm Godden and Susan Irvine, eds. Oxford: Oxford UP, 2009, B-text, 35.117–19, 333. Oxford, Bodleian Library, Bodley 180, fol. 61v.

Chaucer, Geoffrey. Troilus and Criseyde, in The Riverside Chaucer, third edition. Larry D. Benson, ed. Boston: Houghton Mifflin, 1987, 2.820–26, 500.

Cynewulf. Elene, in The Old English Poems of Cynewulf. Robert E. Bjork, ed. Dumbarton Oaks Medieval Library 23. Cambridge: Harvard UP, 2013, lines 1228a–35, 228.

Dictionary of Old English: A to Le, 2024, s.v. heofone, heofone, n.

Fulk, R. D., Robert E. Bjork, and John D. Niles. Klaeber’s Beowulf, fourth edition. Toronto: University of Toronto Press, 2008, lines 1570–72a, 54.

G. S. “Anecdote of the late Harry Fielding.” Scots Magazine, June 1786, 297. Gale Primary Sources: British Library Newspapers.

Kroonen, Guus. Etymological Dictionary of Proto-Germanic, vol. 2. Leiden: Brill, 2013, 220. Archive.org.

Kuhn, Sherman M., ed. The Vespasian Psalter. Ann Arbor: University of Michigan Press, 1965, Psalms 8, 5. Archive.org. London, British Library, Cotton MS Vespasian A.i.

Oxford English Dictionary, third edition, June 2008, s.v. heaven, n.; March 2021, s.v. seventh heaven, n.

Schaefer, Kenneth Gordon. An Edition of Five Old English Homilies for Palm Sunday, Holy Saturday, and Easter Sunday (PhD diss., Columbia University, 1972), 175. ProQuest Dissertations & Theses Global, 7525717. Cambridge, Corpus Christi College, MS 162, 384. Parker on the Web.

Photo credit: Cambridge, Corpus Christi College, MS 162, 384. Parker on the Web. Used under a Creative Commons Attribution Non Commercial 4.0 International license.

spitting image

Astronauts and identical twins Mark and Scott Kelly, 2015

14 October 2024

The phrase spitting image, used to describe someone who looks very much like another person, particularly a close family member, is a relatively recent coinage based on a much older idea. That original idea has disappeared from our collective consciousness, making the phrase a dead metaphor, one that is no longer productive or understood. As a result many variations—folk etymologies—of it and etymythologies about spitting image’s origin have arisen.

That original idea is that of spitting out an exact likeness of oneself. (And that, in turn, may be a euphemistic metaphor for male ejaculation during sex.) We see this idea expressed at the beginning of the seventeenth century. From Nicholas Breton’s 1602 Wonders Worth the Hearing, in which he provides an unflattering description of the participants in a country wedding:

and after the rowte of such a fight of Rascals, as one would rake hell for such a rabblement, followes the Groome my young Colt of a Cart bréed, led betwixt twoo girles for the purpose, the one as like an Owle, the other as like an Urchin, as if they had béene spitte out of the mouthes of them.

John Dryden expresses it in his 1668 play Sir Martin Mar-all, when he has a character say:

My dear Father, I know it is you by instinct; for methinks I am as like you as if I were spit out of your mouth.

By the nineteenth century, the underlying metaphor becomes more hidden, and we see the noun spit, in the phrase the very spit of, being used to express the idea. From Charles Dibdin’s 1897 novel Henry Hooka:.

She had low ideas, was the very spit of her mother, no elegant notions of gentility, a perfect stranger to the delicate feelings with which great minds were sensitively and susceptibly touched.

And by mid century we get the phrase spit and fetch, with fetch being an Irish dialectal term for one’s doppelganger or likeness. From George Augustus Sala’s 1859 Gaslight and Daylight, in a passage describing ship’s figureheads:

They all seem to have been chiselled from the same models, designed in the same train of thought. Caucus, now, with the addition of a cocked hat and epaulettes, and minus an eye or an arm, would be twin-brother to Admiral Nelson, bound to Singapore, close by; with a complete coat of gold-leaf, a fiercely-curled wig and a spiky crown, he would do excellently well for “King Odin.” screw-steamer for Odessa; with an extra leer notched into his face, his whiskers shaved off, and in his hand a cornucopia resembling a horse's nosebag, twisted and filled with turnips, he would pass muster for Peace or Plenty; while with a black face, a golden crown and bust, and a trebly-gilt kitchen-poker or sceptre, he would be the very spit and fetch of Queen Cleopatra. Distressingly alike are they, these figure-heads.

The phrase spitten picter is recorded in William Dickinson’s 1878 glossary of the Cumberland dialect. In his entry we see that a commenter with the initials W.W.S. is unfamiliar with the metaphor of spitting out a copy of oneself and thus suggests a false etymology:

Spitten picter, c. a strong likeness. “Yon barn ’s his varra spitten picter.” (I suspect spitten means pricked. One way of getting a an exact copy of a drawing is to prick out the outline with a pin.—W.W.S.)

Finally, by the end of the nineteenth century, the phrase spitting image, as we know it today, is recorded. From a story “Alone in the Smuggler’s Lair” that appeared in the 9 May 1891 issue of The Boy’s Standard:

And so by that means I got to Truro, and from there I tramped to Penzance, about thirty miles, and having found my uncle, who kept a large ship-chandlery store, I rather startled him. He had never seen me before.

“By Jove!” said he, “you are the very spit and image of your poor dead brother. I only hope you will turn out as good and bright a man.”

We’ve seen how the original idea behind the phrase has been lost. The metaphor is dead, and the phrase spitting image is a linguistic fossil. Such fossils often give rise to wrong ideas about their origins as people try to make sense of them. We’ve also seen one false etymology, that of spitten meaning pricked, but it’s not the last. The folk etymology (that is an alteration of an idiom in an attempt to make sense of it) splitting image appears by 1894. We see it in a poem, Kitty Kirkie’s Kersmassing, written in the Westmorland dialect:

We’re nowt bet human natur, barn,
Soa t’ Kersmas up i' t’ fells
El just be t’ splitten image
Ov a Kersmas ’mang yersells.

(We’re nothing but human nature, child [born?], so the Christmas up at the fells will just be the splitting image of a Christmas among yourselves.)

Another folk etymology/false etymology has it that spitting image is a variation on spirit and image. A nice idea, but wrong.

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Sources:

“Alone in the Smugglers’ Lair.” The Boy’s Standard, 9 May 1891, 28/1. Gale Primary Sources: Nineteenth Century Collections Online.

Breton, Nicholas. Wonders Worth the Hearing. London: E. Allde for John Tappe, 1602, sig. B4r. ProQuest: Early English Books Online.

Dibdin, Charles. Henry Hooka: A Novel, vol. 1 of 3. London: C. Chapple, 1807, 188. Gale Primary Sources: Nineteenth Century Collections Online.

Dickinson, William. A Glossary of Words and Phrases Pertaining to Dialect of Cumberland. English Dialect Society, Series C, 8. London: Trübner, 1878, 92/2. HathiTrust Digital Archive.

Dryden, John. S[i]r Martin Mar-all, or the Feigned Innocence. London: H. Herringman, 1668, 5.1, 60. ProQuest: Early English Books Online.

Horn, Lawrence R. “Spitten Image: Etymythology and Fluid Dynamics.” American Speech, 79.1, Spring 2004, 33–38. Project Muse.

Oxford English Dictionary, second edition, 1989, spit, n.2, spitten, adj., spitting image, n., splitting, n.

Sala, George Augustus. Gaslight and Daylight. London: Chapman and Hall, 1859, 334. HathiTrust Digital Archive.

Wilson, William. “Kitty Kirkie’s Kersmassing.” In Thomas Clarke and William Wilson. Specimens of the Dialects of Westmorland, part second. Kendal: Atkinson and Pollitt, 1894, 36. HathiTrust Digital Archive. (The OED, in an entry dated 1914, gives this citation an 1880 date, but I can only find an 1894 edition that contains this poem. It’s also unclear whether Wilson is the author of the poem or merely the one who contributed it to the book.)

Wright, Joseph. The English Dialect Dictionary, vol. 5 of 6. Oxford: Henry Frowde, 1905, s.v. spit, 669–70. HathiTrust Digital Archive.

Photo credit: NASA/Robert Markowitz, 2015. Wikimedia Commons. Flickr.com. Public domain image.

 

thallium

Photo of silver-colored, crystalline rods among dirt particles

Crystals of hutchinsonite, an ore containing thallium

11 October 2023

Thallium is a chemical element with atomic number 81 and the symbol Tl. It was discovered independently by chemists William Crookes and Claude-Auguste Lamy in 1861, but Crookes was the first to publish and was the one to name the element. The name is from the Greek θαλλός (thallos, green plant shoot) + -ium, after the bright green line in the element’s spectrum.

Crookes published his discovery in March 1861, but the announcement did not propose a name. Two months later, he named it:

I have thought it best to give in the present article a few additional observations which I have since made, and also to propose for it, the provisional name of Thallium, from the Greek θαλλός, or Latin thallus, a budding twig,—a word which is frequently employed to express the beautiful green tint of young vegetation; and which I have chosen as the green line which it communicates to the spectrum recals [sic] with particular vividness the fresh colour of vegetation at the present time.

Thallium and its compounds are highly toxic. Thallium sulfate was once widely used as a pesticide, but this use is now generally banned out of safety concerns. Thallium salts were also used to treat various medical conditions, but these uses have largely been superseded by more effective and safer medicines. It is currently used in the manufacture of optical glass and of electronic components. A radioactive isotope is used in nuclear medicine, and the element may have practical applications in high-temperature superconductors.

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Sources:

Crookes, William. “Further Remarks on the Supposed New Metalloid.” The Chemical News, 3.76, 18 May 1861, 303. HathiTrust Digital Archive.

———. “On the Existence of a New Element, Probably of the Sulphur Group.” The Chemical News, 3.69, 30 March 1861, 193–94. HathiTrust Digital Archive.

Miśkowiec, Pawel. “Name Game: The Naming History of the Chemical Elements: Part 2—Turbulent Nineteenth Century.” Foundations of Chemistry, 8 December 2022. DOI: 10.1007/s10698-022-09451-w.

Oxford English Dictionary, second edition, 1989, s.v. thallium, n.

Photo credit: Robert M. Lavinsky, before 2010. Wikimedia Commons. Licensed under a Creative Commons Attribution-Share Alike 3.0 Unported license.