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Alchemical and archaic chemistry terms

Part I (A-K)

Originally prepared by Carmen Giunta at with some later additions by Gleb Butuzov
Partial list of sources:
Julius Grant, Chemical Dictionary, 3rd ed. (Philadelphia: Blakiston, 1944)
James Bryant Conant, ed., Harvard Case Histories in Experimental Science, vol. 1 (Cambridge, MA: Harvard, 1957)
W. E. Flood, The Dictionary of Chemical Names (New York: Philosophical Library, 1963)
Frederick Soddy, "Radioactivity", Chemical Society Annual Reports 10, 262-88 (1913)

Go to Part II (L-Z)


acid of shugar: oxalic acid.

acidum salis: hydrochloric acid (HCl, marine acid, muriatic acid, spirit of salt); literally "acid of salt".

ad siccum: to dryness, as in evaporation to dryness.

aer fixus: fixed air

aether: ether. Aether nitri, literally "nitric ether", was ethyl nitrate (C2H5NO3)

aes cyprium. Cyprian brass or copper.

air: formerly a general term for any gas (elastic fluid).

alembroth, salt of: a double chloride of mercury and ammonium, Hg2(NH4)2Cl4.H2O.

algaroth, powder of: antimony oxychloride (SbOCl), an emetic named after its inventor, a Vittorio Algarotti.

alkahest: a term invented by Paracelsus to denote a universal solvent.

alkali: a basic substance. Caustic alkalis were usually hydroxides, while mild alkalis were carbonates. (See alkaline air, fossil alkali, marine alkali, mineral alkali, vegetable alkali, volatile alkali.)

alkaline air: ammonia gas (NH3); see spirit of hartshorn, volatile alkali.

alcanet root - alcanna tinctoria.

alum: originally potassium aluminum sulfate (i.e., KAl(SO4)2); more recently the term also includes salts in which sodium or ammonium substitute for potassium.

antimony. From latin 'antimonium' used by Constantinius Africanus (c. 1050) to refer to Stibnite.

aqua fortis: nitric acid (HNO3, nitrous acid, spirit of nitre).

aqua regia or aqua regis: a mixture of concentrated nitric and hydrochloric acids capable of dissolving the "royal metal" gold.

aqua tofani. Arsenious oxide. Extremely poisonous. Used by Paracelsus.

aqua vitae: concentrated aqueous ethanol (C2H5OH), typically prepared by distilling wine [Arnald of Villanova] (spirit of wine)

Armenian bole: red clay.

atom: does not necessarily correspond to the modern picture of the ultimate particle of an element. For example, Dalton meant something more along the lines of "ultimate particle of a substance"; to him the smallest unit of a chemical compound was a compound atom (molecule in modern terminology), while the smallest particle of a chemical element was a simple atom (now just atom, although several of Dalton's simple atoms turned out to be molecules of elements, such as O2). (See molecule.)

aurum fulminans (fulminating gold): gold hydrazide (AuHNNH2), an olive-green powder that can explode on concussion.

azote: nitrogen, named because it did not support respiration and was therefore "lifeless" (N2, phlogisticated air; see also mephitic air).

barilla: impure sodium carbonate extracted from soap-wort.

baryta and barytes: were both used for the earth from which barium was eventually isolated, namely barium oxide (BaO). Barytes can also refer to barite, a barium sulfate (BaSO4) mineral also known as heavy spar. Baryta can also refer to barium hydroxide or its hydrate. Barytium is an older name for barium.

benzine: ligroin or petroleum ether; sometimes benzene (C6H6)

bismuth: often the ore for extracting mercury

bismuth glance (bismuth sulphide)-- apparently a shiny substance

bittern: solution of magnesium salts

black ash: impure sodium carbonate

black lead: graphite, an allotrope of carbon

bleaching powder: calcium chloro-hypochlorite (CaOCl2).

blende (German 'deceptive': zinc sulphide)--because it looked like galena (lead sulphide), but produced no lead.

blue stone: copper sulphate.

boule (bole): bole armeniac.

brimstone: sulfur (S).

butter: In addition to its still current meanings of a low-melting vegetable fat or a high milk-fat foodstuff, a butter could be a soft substance such as an inorganic chloride. Butter of antimony was antimony trichloride (SbCl3), named so because of its waxy quality, butter of arsenic was arsenic trichloride (AsCl3), butter of tin was a hydrate of tin tetrachloride (SnCl4.5H2O), and butter of zinc was zinc chloride (ZnCl2)

butter of tin: hydrated stannic chloride.

Cadet's fuming liquid (Cadet's liquid): heavy brown liquid first prepared by the French chemist Louis Claude Cadet de Gassicourt. Cadet's liquid is highly toxic, smells strongly of garlic, and spontaneously bursts into flame when exposed to air. It is mainly cacodyl oxide ([(CH3)2As]2O) with other cacodyl compounds such as dicacodyl ([(CH3)2As]2). Berzelius coined the name kakodyl (later changed to cacodyl) for the dimethylarsinyl radical ((CH3)2As) from the Greek kakodes (evil-smelling) and hyle (matter).

cadmia, which was also called Tuttia or Tutty, was probably zinc carbonate.

calamine. Zinc carbonate.

calcareous earth: calcium oxide (CaO, lime, quicklime). Caustic calcareous earth was calcium hydroxide (Ca(OH)2, slaked lime) and mild calcareous earth was calcium carbonate (CaCO3, chalk, carbonate of lime).

calces: See calx.

calcination: formation of a calx, i.e., oxidation of a metal, often by roasting.

calomel. Mercurous chloride. Purgative, made by subliming a mixture of mercuric chloride and metallic mercury, triturated in a mortar. This was heated in a iron pot and the crust of calomel formed on the lid was ground to powder and boiled with water to remove the very poisonous mercuric chloride.

caloric: a postulated elastic fluid associated with heat flow.

calx (plural calces): a metal oxide (earth), the result of roasting a metal or mineral. Sometimes used for a particular calx, namely lime. Name like calx of mercury (mercuric oxide) was virtually a recipe for its creation; a calx was a powder formed by roasting a mineral or metal, generally what we would call an oxide.

carbonic acid: carbon dioxide (CO2, fixed air)

carbonic oxide: carbon monoxide (CO)

carburetted hydrogen: methane (CH4)

cathode rays: streams of electrons issuing from the cathode of an evacuated tube. They were identified as what are now called electrons late in the 19th century.

caustic marine alkali. Caustic soda. Sodium hydroxide. Made by adding lime to natron.

caustic volatile alkali. Ammonium hydroxide.

caustic wood alkali. Caustic potash. Potassium hydroxide. Made by adding lime to potash.

ceruse: lead carbonate (PbCO3)

chalk: calcium carbonate (CaCO3, carbonate of lime, mild calcareous earth). Acid of chalk is carbon dioxide (CO2, carbonic acid, fixed air)

charcoal: either a charred carbonaceous material or its primary constituent, namely carbon. Lavoisier coined the term carbone (carbon) to distinguish the element from impure charred material; however, the distinction was not universally adopted right away.

caustic potassa: hydrate potassium.

caustic soda: sodium hydroxide.

Chili niter: sodium nitrate.

chrome green: chromic oxide.

chrome orange. Mixture of chrome yellow and chrome red.

chrome red. Basic lead chromate.

chrome yellow. Lead chromate.

chymical: sometimes the modern term alchemical is more accurate than chemical. Similarly chymist often means alchemist.

cinnabar or vermillion. Mercuric sulphide.

cobalt. Named by the copper miners of the Hartz Mountains after the evil spirits the 'kobolds' which gave a false copper ore; despised because of its uselessness and unhealthiness (it was often found mixed with arsenic), and because it resembled silver but wasn't.

colcothar: iron (III) oxide (Fe2O3) by-product from sulfuric acid manufacture.

common salt. Sodium chloride.

copper glance. Cuprous sulphide ore.

copper-nickel, named for another devil, because it looked like copper but wasn't-- our nickel.

copperas: iron (II) sulfate (FeSO4.7H2O, green vitriol); blue copperas: copper sulphate.

corpuscle: generally (and still) a small particle; in the late 19th and early 20th centuries, a competing name for the electron.

corrosive sublimate of mercury: mercuric chloride (HgCl2).

cream of tartar: bitartrate potassium.

creech: calcium sulfate (CaSO4)

cuprite. Red cuprous oxide ore.

dephlogisticated air: oxygen (O2, pure air, vital air); see phlogiston.

dephlogisticated marine acid: chlorine (Cl2, oxymuriatic acid). See marine acid.

didymium: a mixture of praseodymium (Pr) and neodymium (Nd) believed to be an element until 1885.

Dragon's blood: (sometimes) resin from Rattan palm fruit.

dram (drachm): unit of apothecary weight equal to 3.888 g. fluid dram: unit of volume equal to 1/8 fluid ounce (3.55 mL)

dry alum: sulphate aluminium & potassium.

Dutch oil (Dutch liquid, Oil of the Dutch chemists): ethylene chloride, (C2H4Cl2) first prepared by the action of chlorine on ethylene (hence olefiant gas) in 1794 by four Dutch chemists Johann Rudolph Deimann, Adrien Paets van Troostwyck, Anthoni Lauwerenburgh and Nicolas Bondt.

Dutch White. Mixture of one part of white lead to three of barium sulphate.

earth: a metal oxide (calx); see calcareous earth, magnesian earth, siliceous earth.

elastic fluid: usually a descriptive term for gas (air); however, certain elastic fluids were postulated which correspond to no material (caloric, ether, phlogiston).

emanation: a radioactive gas (radon) produced in the decay of other radioactive elements. Specifically, thorium emanation (also thoron) is 220Rn (half life = 55 s) produced from the decay of thorium; radium emanation is 222Rn (half life = 3.8 d) produced from the decay of radium; actinium emanation is 219Rn (half life = 4 s).

epsom salts: sulphate of magnesia.

ether (or aether; sometimes luminiferous ether): a hypothetical elastic fluid postulated to support the transmission of light. (The organic chemistry meaning is still current: namely an organic compound whose formula is ROR', where R and R' are alkyl or aryl groups; especially diethyl ether (C2H5OC2H5).)

Ethiops mineral black: sulphide of mercury.

Fahrenheit scale: temperature scale devised in 1717 by G. D. Fahrenheit and denoted by °F. The normal freezing point of water is 32°F and the normal boiling point of water is 212°F.

fixed air (aer fixus): carbon dioxide (CO2, carbonic acid).

flowers of antimony (arsenic trioxide), obtained by roasting orpiment or realgar (arsenic di- and trisulphide)-- which are beautiful names themselves. Antimony and arsenic have similar properties and were often confused; their compounds were not really disentangled till the 19th century. Antimony was very popular in medieval times as a medicine, and the confusion with arsenic probably prematurely dispatched many a patient.

flowers of sulphur. light yellow crystalline powder, made by distilling sulphur.

flowers of zinc: crude zinc oxide (ZnO, pompholix). Found as a deposit in zinc chimneys. "Flower" means "flour" here; the words are etymologically the same.

fluoro acid air: silicon tetrafluoride (SiF4).

fool's gold (iron sulphide).

fossil alkali: sodium carbonate (common mineral alkali, marine alkali, soda)

fulminating gold. Made by adding ammonia to the auric hydroxide formed by precipitation by potash from metallic gold dissolved in aqua regis. Highly explosive when dry.

fulminating silver. Silver nitride, very explosive when dry. Made by dissolving silver oxide in ammonia.

funiculus: an invisible membrane postulated to hold up a column of mercury in the Torricellian experiment [Linus]

galena: native lead sulfide (PbS), or lead or silver ore, or the slag remaining after refining lead.

glass of Antimony. Impure antimony tetroxide, obtained by roasting stibnite. Used as a yellow pigment for glass and porcelain.

Glauber's salt: sodium sulfate (Na2SO4.10H2O, sal mirabilis)

glucinium or glucinum: beryllium (Be).

grain : unit of mass. For late 18th-century French system, see livre.

green lion -- a widely used alchemical term; Vera Prima Materia of the Stone, often confused with iron sulphate.

green copperas, yet another name for green vitriol (iron sulphate). Copperas, 'coppery water', should have been restricted to copper sulphate.

gros: Unit of mass in late 18th-century France; see livre.

gypsum. Calcium sulphate.

hartshorn (spirits of): ammonia; (slats of) ammonium carbonate.

hepar: This Latin word for liver referred to reddish-brown (i.e., liver-colored) metal sulfides. (See sulphuret.) Hepar sulphuris (liver of sulphur) was a synonym either for potassa sulphurata (a mixture of various compounds of potassium and sulfur made by fusing potassium carbonate and sulfur) or, in homeopathic contexts, for calcium sulfide (CaS).

hepatic air: hydrogen sulfide (H2S, sulphuretted hydrogen)

horn silver, argentum cornu. A glass like ore of silver chloride.

igneous fluid: a postulated elastic fluid sometimes used synonymously with caloric (matter of heat), sometimes with phlogiston (matter of fire), and sometimes as a substance with the postulated properties of both.

inflammable air: hydrogen (H2).

ionium: an isotope of thorium produced in uranium decay, namely 230Th (half-life = 80 kyr).

Jeweller's Putty: oxide of tin.

kelp: ashes of seaweed from which carbonates or iodine were extracted

Kelvin scale: an absolute temperature scale (i.e., one in which absolute zero is assigned the value zero) named after William Thomson, first (and last) Baron Kelvin of Largs, who first proposed an absolute temperature scale. One Kelvin (denoted simply K or sometimes in older sources °K) is the same size as a Celsius degree, so the normal boiling point of water is 273.15 K and the normal boiling point is 373.15 K.

King's Yellow. A mixture of orpiment with white arsenic.

Go to Part II (L-Z) of the Alchemical and archaic chemistry terms