element, compound, or alloy that is a good conductor of both electricity and heat

A metal (from Ancient Greek μέταλλον (métallon) 'mine, quarry, metal') is a material that, when freshly prepared, polished, or fractured, shows a metallic lustre, allows thermal conduction and is an electrical conductor. Metals typically have properties of ductility (may be drawn by tension into wire) and malleability (formable under compression). These properties are the result of metallic bonding between the atoms or molecules of the metal. A metal may be a chemical element such as iron; an alloy such as stainless steel; or a molecular compound such as polythiazyl. Metals are usually inclined to form cations through electron loss. Most will react with oxygen to form oxides.

Melting metal for casting


Mercury Fountain
  • While Paracelsus was pressing his doctrines on all sides, and endeavouring to lead chemistry into a new channel, another, Agricola, was quietly at work among the mines of Saxony, utterly indifferent to all but the advance of his science. It is to Agricola's systematic observations that we trace the beginnings of the science of mineralogy. In metallurgy, also, he was a pioneer, the first to give a clear and succinct account of the preparation of many metals. He taught the condensation and purification of sulphur given off during the roasting of many ores, the separation of silver from gold by means of nitric and sulphuric acid, the preparation of such bodies as salt, alum, and saltpetre on a large scale. The apparatus described by Agricola and employed by him for the smelting and testing of ores were still in use at the end of the eighteenth century. Agricola stands out solitary among the men of his time as one pursuing chemistry from pure love of the science; his work had no other aim than the increase of knowledge.
Historical Metal Working
  • Iron yields to certain degrees of beatings or repeated pressure; its impenetrable molecules, purified by man and made homogeneous, disintegrate; and, without being in fusion, the metal no longer has the same virtue of resistance. Marshals, locksmiths, tool makers, all the workers who constantly work this metal then express the state of it by a word of their technology: "The iron is retty!" they say, appropriating this expression exclusively devoted to hemp, the disorganization of which is obtained by retting. Well, the human soul, or if you will the threefold energy of body, heart, and spirit, is in an iron-like situation, as a result of certain repeated shocks. It is thus with men like hemp and iron — they are retty.
    • Honoré de Balzac, Splendeurs et misères des courtisanes or The Splendors and Miseries of Courtesans (1838-1847) part IV. La dernière Incarnation de Vautrin or The Last Incarnation of Vautrin, Les Adieux or Farewells.
  • A neutral salt, which is composed of an acid and alkali, does not possess the acrimony of either of its constituent parts. It can easily be separated from water, has little or no effect upon metals, is incapable of being joined to inflammable bodies, and of corroding and dissolving animals and vegetables; so that the attraction both of the acid and alkali for these several substances, seems to be suspended till they are again separated from one another.
  • One worker on one of the supports... either manually or with a trowel distributes the mortar over the chicken wire... Simultaneously, another worker from within the room... holds the mortar which is applied from the outside with a metal float or trowel in order that the mortar does not fall. Once this operation is completed, the required finish is applied both from the outside and the inside.
    • J. Castro, "Ferrocement Roofing Manufactured on a Self-Help Basis" (July, 1977) Universidad Autonoma Metropolitana Mexico, Journal of Ferrocement, Vol. 7, No. 1, pp. 17-27.
  • The export of aluminium into Italy was strictly forbidden; but aluminium was almost the only metal that Italy produced in quantities beyond her own needs. The importation of scrap iron and iron ore into Italy was sternly vetoed in the name of public justice. But as the Italian metallurgical industry made but little use of them, and as steel billets and pig iron were not interfered with, Italy suffered no hindrance. Thus, the measures pressed with so great a parade were not real sanctions to paralyse the aggressor, but merely such half-hearted sanctions as the aggressor would tolerate, because in fact, though onerous, they stimulated Italian war spirit. The League of Nations, therefore, proceeded to the rescue of Abyssinia on the basis that nothing must be done to hamper the invading Italian armies. These facts were not known to the British public at the time of the election. They earnestly supported the policy of the sanctions, and believed that this was a sure way of bringing the Italian assault upon Abyssinia to an end.
  • The Franklin sold at £4. 6s, each at the furnace, and at Philadelphia £18 per ton, the price varying with the metal.
    • William Watts Hart Davis, Warren Smedley Ely, John Woolf Jordan, History of Bucks County, Pennsylvania From the Discovery of the Delaware to the Present Time Vol. II (1905) p. 148.
Iron pillar of Delhi
  • The art of tempering and casting iron developed in India long before its known appearance in Europe; Vikramaditya, for example, erected at Delhi (ca. 380 A.D.) an iron pillar that stands untarnished today after fifteen centuries; and the quality of metal, or manner of treatment, which has preserved it from rust or decay is still a mystery to modern metallurgical science. Before the European invasion the smelting of iron in small charcoal furnaces was one of the major industries of India. The Industrial Revolution taught Europe how to carry out these processes more cheaply on a larger scale, and the Indian industry died under the competition. Only in our own time are the rich mineral resources of India being again exploited and explored.
    • Will Durant, Our Oriental Heritage (1935) Part 1. Our Oriental Heritage p. 478 (1942 edition).
  • [T]here are not really 2-dimensional metals because conventional metals, for physics reasons... don't really like to be in the 2-D state, and most of them immediately oxidize anyway... So by discovering MXenes... we created materials which are 2-dimensional metals. So we... closed the gap in existing the series of materials.
  • Tradition has it that Menes not only concerned himself with the unification of Egypt but also with the control of the river: to him is attributed the first damming of the Nile, the digging of dikes for agricultural purposes and indeed the first attempt to control and apportion the waters of the river. The wealth of Egypt was thus, with Mesopotamia, based upon its agricultural output. However, unlike Mesopotamia, the Egyptians had on their doorstep a number of mineral resources that they were able to exploit with little effort, including copper ores, gold and a wide range of rocks suitable for building and the making of a wide variety of ornaments.
    [S]hortly before the year 3000 metallurgists made a discovery that was to transform the entire "industry." mixing a small quantity of tin ore with the copper ores when... smelted... they discovered the alloy bronze. The occurrence of tinstone... does not occur in the same type of deposit as do the ores of copper, but rather, [near] veins of gold. ...Thus tinstone ...may well have been noticed during washing for gold... finding that the little black lumps of ore were relatively heavy, presumably made various attempts at smelting them until they arrived empirically at a suitable alloy... [T]he effect is to reduce the melting point... they had a far more fluid metal that was much easier to cast. ...the quality of casting improved dramatically.
    • Henry W. M. Hodges, Technology in the Ancient World (1970) Ch. 4 Of Monuments, Ships, Metallurgy and Military Technology (3000-2000 B.C.)
  • Aristotle had considered metals to be formed by the combination of moist and dry exhalations, and in the Jabirian works these... are... vapours of mercury and sulphur. The cause of the different metals was the... quality of the sulphur... The term sulphur a component of metals probably referred to a volatile combustible material to which no... substance corresponded exactly. Likewise mercury... may... have been... an approximation to the other volatile liquid component of metals. ...The notion that metals contained a combustible principle persisted, and... provided the inspiration for the phlogiston theory.
    • John Hudson, The History of Chemistry (2017) p. 23.
  • The Jabirian alchemists... believed that metals were ultimately composed of the four Aristotelian elements earth, water, air and fire... A base metal had to be treated with a medicine or elixir to adjust... qualities... with the proportions of gold. ...[Q]ualities of heat, cold, moisture and dryness could each be separated in pure form. ...First they subjected various organic materials to dry distillation... which often resulted in... a volatile combustible... (air), a liquid (water), a combustible tarry material (fire) and a dry residue (ash). [Each of] [t]hese elements were supposed... composed of two qualities, and... could be isolated by... purification. Thus water... could be converted into pure cold by repeated distillation... and further [distillations] in the presence of a drying agent. The resulting pure cold... a brilliant white solid.
    • John Hudson, The History of Chemistry (2017) p. 23.
    Lambot's bateau (1848)
Brignoles Museum, France
  • My invention shows a new product which helps to replace timber where it is endangered by wetness, as in wood flooring, water containers, plant pots, etc. The new substance consists of a metal net of wire or sticks which are connected or formed like a flexible woven mat. I give this net a form which looks in the best possible way, similar to the articles I want to create. Then I put in hydraulic cement or similar bitumen tar or mix, to fill up the joints.
    • Joseph-Louis Lambot (ca. 1841) translation by Gainor W. Jackson, W. Morley Sutherland, Concrete Boatbuilding: Its Technique and Its Future (1969) as quoted in "State-of-the-Art Report on Ferrocement", ACI 549R-97 (1997) ACI Committee 549.
Strasbourg Cathedral
pipe organ
  • Nothing can vex the Devil more
    Than the name of him whom we adore.
    Therefore doth it delight me best
    To stand in the choir among the rest,
    With the great organ trumpeting
    Through its metallic tubes, and sing:
    Et verbum caro factum est! [And the Word was made flesh!]
    These words the devil cannot endure,
    For he knoweth their meaning well!
    Him they trouble and repel,
    Us they comfort and allure,
    And happy it were, if our delight
    Were as great as his affright!
    • Henry Wadsworth Longfellow, Christus: A Mystery (1872) Part II. The Golden Legend: Second Interlude. Martin Luther. A Chamber in the Wartburg. Morning. Martin Luther Writing. Martin Luther.
  • In the history of war and society we single out three main innovations to describe significant changes before 1800: the introduction of metal, when humans abandoned stone weapons for ones made from bronze and iron; the domestication of the horse, which gave warriors greater mobility and speed; and the introduction of gunpowder, which transformed war on land and at sea. (Since other parts of the world, such as the Americas, did not have horses until the Europeans brought them in the sixteenth century and some parts of the world, such as Australia, never developed metal weapons, not all human societies have experienced change at the same time.) In each case, of course, many other things were happening both to technology and to society. Metal weapons were only a part of the story: societies had to develop the soldiers and the infrastructures to make use of them. Horses were more formidable when the wheel enabled them to pull chariots or later on when they could carry armed warriors. The introduction of gunpowder too was accompanied by other important developments: in metallurgy, for example, so that guns did not explode when they were fired, or in the design and navigation of ships, so that they could make use of the new cannon.
  • The metals are all essentially identical; they differ only in form. Now, the form brings out accidental causes, which the experimenter must try to discover and remove, as far as possible. Accidental causes impede the regular union of sulphur and mercury; for every metal is a combination of sulphur and mercury. A diseased womb may give birth to a weakly, leprous child, although the seed was good; the same is true of the metals which are generated in the bowels of the earth, which is a womb for them; any cause whatever, or local trouble, may produce an imperfect metal. When pure sulphur comes in contact with pure mercury, after more or less time, and by the permanent action of nature, gold is produced.
  • Mercury as a liquid metal is capable of dissolving other metals and forming metallic solutions. These are generally called 'amalgams.' The formation of these solutions is often accompanied by the development of a large amount of heat—for instance when potassium and sodium are dissolved... but sometimes heat is absorbed, as... when lead is dissolved. ...[T]he solution of metals in mercury is accompanied by the formation of definite chemical compounds of the mercury with the metals dissolved. ...[I]n many cases such compounds have undoubtedly been obtained, and their existence is clearly shown by the evident crystalline structure and characteristic appearance of many amalgams.
Bramley, Holy Trinity Church
  • Sonorous metal blowing martial sounds,
    At which the universal host up sent
    A shout that tore hell's concave, and beyond
    Frighted the reign of Chaos and old Night.
  • Few would defend a small view of Alchemy as "Mother of Chemistry", and confuse its true goal with those external metal arts. Alchemy is an erotic science, involved in buried aspects of reality, aimed at purifying and transforming all being and matter. Not to suggest that material operations are ever abandoned. The adept holds to both the mystical and physical work.
    • Jim Morrison, in The Lords and the New Creatures: Poems (1969), The Lords: Notes on Vision.
  • The history of science may be described as the breaking down, and the crumbling away, of artificially constructed barriers. All the great men of science have been famous wall-breakers. ...It is worthy to remark that the central conception of the alchemists ...was the unity of natural phenomena. ...[T]heir arguments would be somewhat as follows—Plants grow from seeds ...animals become larger, stronger, and more complete ...the plant may well be called more perfect than the seed, and the full grown animal more perfect than the immature ...both plants and animals grow, come to their prime, and decay; and there are degrees of perfection in the animal and vegetable worlds. Now—we may suppose the argument of the alchemist... minerals and metals and all inanimate things should grow, and change, from less perfect to more perfect forms; as there are degrees of perfectness and dignity in among all living things, so... among all things; some metals disappear in acrid liquids, and... are... easily worn away, they are readily melted and burnt to dross; but some other metals are not swallowed up by corrosive liquids, nor... worn away with ease, nor readily changed in fire; there are evidently noble and base metals, perfect and imperfect metals; and as the less perfect seed... produces the more perfect plant... rendered yet more perfect by cultivation, so the imperfect metals change slowly into... more perfect, and this... can be hastened by man's art and devices. ...[L]iving things are more perfect that inanimate things ...[M]uch more must changes from immature to mature forms be constantly proceeding from dead things like minerals and metals ...[I]t is probable that the plasticity of the minerals and metals will be greater ...hence will be a comparatively easy thing to grow a noble metal like gold from ignoble metals like lead and copper, although it is impossible to change one kind of animal into another or one sort of plant into another ...
    A vague conception of the unity of nature... led to little accurate knowledge..; all that could be done was to perform a vast number of inaccurate and incomplete experiments, and to state the results in loose and slipshod language of the vague but sonorous hypothesis which prompted the experiments. And so although the hypothesis postulated the unity of nature there was no unity in the experimental results... collected to support the hypothesis. ...A man who sets out to discover what is must endeavour to put aside all his notions of what ought to be; it is only when he has gained a solid foundation of verified and accurate facts that he may venture to make a definite guess concerning the cause ...but unless he makes clearly stated guesses ...scientific hypotheses—he will remain a mere collector of half facts ...
  • M. M. Pattison Muir, The Story of the Chemical Elements (1897) pp. 16-19.
  • RECOMMENDATION 6: Ferrocement in Disaster Relief.
    After fires, floods, droughts, and earthquakes... [t]ransportation is often disrupted... Supplies of bulky conventional building materials may be stranded outside the disaster area, whereas the basic ingredients of ferrocement may be available on the site or easily transported. The versatility of ferrocement also reduces logistical supply problems: wire mesh, cement, sand, and water can be substituted for the metal used for roofing, woods or plastic for shelters and clinics, asphalt for helipads, steel for bridges, and so on. Moreover, most ferrocement structures, though built for an emergency, will last long after the emergency is over. ...[F]errocement could be used at a disaster site for many purposes: Transport facilities, from simple boats to barges, docks, marinas, helipads, and simple floating bridges or short footbridges as well as road repairs. ...Food-storage facilities, quickly designed to local needs and quickly built, to preserve emergency food supplies. ...Emergency shelters such as, for example, the quonset type of roof, which is easy to erect and highly efficient. ..Public health facilities, such as latrines and clinics, built with ferrocement roofs and stucco-type walls of the same wire mesh and mortar. ...[C]adres of ferrocement workers could be trained in emergency applications and the supervision of local laborers at the disaster site.
  • From this epocha the hypothesis of the tria prima seems wholly to have been abandoned: whilst a very different doctrine was proposed by Beccher in his Physica Subterranea [1669], and to which we are perhaps indebted for the present advanced state of chemical science; since he was the first to point out chemical analysis as the only true method of ascertaining the elements of bodies. According to his doctrine, all terrestrial bodies are composed of water, air, and three earths; viz. the fusible, the inflammable or sulphureous, and the mercurial. The three earths, combined in nearly equal proportions, compose the metals: when the proportion of mercurial earth is very small, they compose stones; when the fusible predominates, the resulting compounds are the precious stones; when the sulphureous predominates, and the fusible is deficient, the compounds are the calorific earths: fusible earth and water compose an universal acid, very much resembling sulphuric acid, from which all other acids derive their acidity; water, fusible earth, and mercurial earth, constitute common salt; sulphureous earth and the universal acid form sulphur.
    Such was the theory of Beccher, which was afterward considerably modified by Stahl.
    • William Nisbet, A General Dictionary of Chemistry Containing the Leading Principles of Science, in regard to Facts, Experiments, and Nomenclature, for the Use of Students (1805) pp. 257-258.
Bicycle Rohloff Speedhub Parts
  • I've noticed that people who have never worked with steel have trouble seeing this... that the motorcycle is primarily a mental phenomenon. They associate metal with given shapes... pipes, rods, girders, tools, parts... all of them fixed and inviolable, and think of it as primarily physical. But a person who does machining or foundry work or forge work or welding sees "steel" as having no shape at all. Steel can be any shape you want if you are skilled enough, and any shape but the one you want if you are not.
  • Alchemical theory was essentially static throughout the medieval period. ...Paracelsus was the herald of a new era, an era of iatrochemistry. His contribution to alchemical theory lay in the addition to sulphur and mercury of a third principle, which he called 'salt.' Materially this was recognised as the principle of uninflammability and fixidity. ...[T]he tria prima, or three 'hypostatical principles' could be interpreted in either a material or a spiritual sense. In the words of Paracelsus himself: 'Know, then, that all the seven metals are born from a threefold matter... Mercury is the spirit, Sulphur is the soul, and Salt is the body... the soul... unites those two contraries, the body and spirit, and changes them into essence.' ...similar to the material effect of the liquid menstruum, or Hermetic Stream, in uniting sophic sulphur and sophic mercury to produce the Philospher's Stone.
    • John Read, From Alchemy to Chemistry (1957) p. 24.
Pierre & Marie Curie (1895)
  • It seemed probable that the large activity of some of these minerals, compared with uranium and thorium, was due to the presence of small quantities of some very active substance, which was different from the known bodies thorium and uranium. This supposition was completely verified by the work of M. and Mme Curie, who were able to separate from pitchblende by purely chemical methods two active bodies, one of which in the pure state is over a million times more active than the metal uranium. This important discovery was due entirely to the property of radio-activity possessed by the new bodies. The only guide in their separation was the activity of the products obtained. ...The activity of the specimens thus served as a basis of rough qualitative and quantitative analysis, analogous in some respects to the indication of the spectroscope.
  • The magnetism as exhibited in iron is an isolated phenomenon in nature. What it is that makes this metal behave so radically different from all other materials in this respect has not yet been ascertained, though many theories have been suggested. As regards magnetism, the molecules of the various bodies behave like hollow beams partly filled with a heavy fluid and balanced in the middle in the manner of a see-saw. Evidently some disturbing influence exists in nature which causes each molecule, like such a beam, to tilt either one or the other way. If the molecules are tilted one way, the body is magnetic; if they are tilted the other way, the body is non-magnetic; but both positions are stable, as they would be in the case of the hollow beam, owing to the rush of the fluid to the lower end. Now, the wonderful thing is that the molecules of all known bodies went one way, while those of iron went the other way. This metal, it would seem, has an origin entirely different from that of the rest of the globe. It is highly improbable that we shall discover some other and cheaper material which will equal or surpass iron in magnetic qualities.
  • [M]etals remained the alchemists' chief concern... they seemed in their own way alive, whereas the calces (oxides) from which they were manufactured crumbled to dust and looked like cinders. Theory at once suggested a natural analogy. The metal was formed from the calx by the incorporation of pneuma or spirit; and this theory of metal-formation long remained in favour, being revived around 1700 as the 'phlogiston' theory. The central problem about metals was to identify the volitile constituents which combined with the calces to form the finished metal. For a long time, the status of quicksilver was ambiguous... resembling much more the volatile reagents which corrode metallic surfaces: mercury, in fact, forms an amalgam with other metals, and is even capable of dissolving gold... So the Alchemy of Avicenna classed mercury as a 'spirit' rather than a 'body'...
by Humphry Davy is a brief sketch of the history of chemistry contained in the Introduction to The Elements of Chemical Philosophy (1812) Part I. Vol. I.; and in the Introduction to Vol. IV of the Collected Works of Sir Humphry Davy (1840) ed. John Davy.
Pouring gold
  • Theophrastus, the successor of Aristotle, ...says, in the beginning of his book on fossils, 'stones are produced from earth, metals from water.' ...Theophrastus is perhaps the best observer among the ancients, whose works are in our possession, and [his] theories... cannot be considered as an unfavourable specimen of the theoretical physics of the age.
    • pp. 5-6.
  • [E]early chemical discoveries led to the pursuit of alchemy, the objects of which were to produce a substance capable of converting all other metals into gold: and an universal remedy calculated indefinitely to prolong the period of human life.
    • p. 10.
  • The processes supposed to relate to the transmutation of metals, and the elixir of life, were probably first made known to the Europeans during the time of the crusades...
    • p. 11-12
  • Arnald of Villa Nova... was one of the earliest European inquirers who attended to chemical operations. ...[H]e firmly believed in the transmutation of metals; the same opinions are attributed to him and to Geber; and he seems to have followed the study with no other views than those of preparing medicines, and attempting the composition of the philosopher's stone.
    • p. 13.
  • Beccher, ...after having studied with minute attention, the operations of metallurgy, and the phænomena of the mineral kingdom, formed the bold idea of explaining the whole system of the earth by the mutual agency and changes of a few elements. And by supposing the existence of a vitrifiable, a metallic, and an inflammable earth, he attempted to account for the various productions of rocks, crystalline bodies, and metallic veins, assuming a continued interchange of principles between the atmosphere, the ocean, and the solid surface of the globe, and considering the operations of nature as all capable of being imitated by art.
    • p. 29.
  • Cobalt had been used to tinge glass in Saxony in the sixteenth century; but the metal was unknown till the time of Brandt, and this celebrated Swedish chemist discovered it in 1733.
    • p. 49.
  • The properties of manganese, which was announced as a peculiar metal by Kaim in 1770, were minutely investigated by Scheele and Bergman a few years after.
    • p. 49.
  • Platina had been brought into Europe and examined by Lewis in 1749 and in 1803, Descotils, Fourcroy, and Vauquelin announced a new metallic substance in it; but the complete investigation of the properties of this extraordinary body was reserved for Messrs. Tennant and Wollaston, who in 1803 and 1804 discovered in it no less than four new metallic substances, besides the body which exists in it in the largest proportion, namely, iridium, osmium, palladium, and rhodium.
    • p. 50.
  • By researches, the commencement of which is owing to Messrs. Nicholson and Carlisle, in 1800, which were continued by Cruickshank, Henry, Wollaston, Children, Pepys, Pfaff, Desormes, Biot, Thenard, Hissinger, and Berzelius, it appeared that various compound bodies were capable of decomposition by electricity; and experiments, which it was my good fortune to institute, proved that several substances which had never been separated into any other forms of matter in the common processes of experiment, were susceptible of analysis by electrical powers; in consequence of these circumstances, the fixed alkalies and several of the earths have been shewn to be metals combined with oxygene; various new agents have been furnished to chemistry, and many novel results obtained by their application, which at the same time that they have strengthened some of the doctrines of the school of Lavoisier, have overturned others, and have proved that the generalizations of the Antiphlogistic philosophers were far from having anticipated the whole progress of discovery.
  • From the first discovery of the production of metals from rude ores, to the knowledge of the bleaching liquor, chemistry has been continually subservient to cultivation and improvement.
    • p. 58.
  • The relations of the common metals to the bases of the alkalies and earths, and the gradations of resemblance between the bases of the earths and acids, point out as probable a similarity in the constitution of all inflammable bodies; and there are not wanting experiments, which render their possible decomposition far from a chimerical idea.
    • p. 60.
Thomas Edward Thorpe, ed., Sir Henry E. Roscoe
  • The whole work was done under conditions of great mental excitement. His cousin Edmund Davy,.. his assistant, relates that when he [Humphrey Davy] saw the minute globules of the quicksilver-like metal burst through the crust of potash and take fire, his joy knew no bounds; he actually danced about the room in ecstasy, and it was some time before he was sufficiently composed to continue his experiments. The rapidity with which he accumulated results after this first feeling of delirious delight had passed was extraordinary.
    • pp. 114-115.
  • Before the middle of November he had obtained most of the leading facts. In a letter dated November 13th he tells W. H. Pepys
"I have decomposed and recomposed the fixed alkalies, and discovered their bases to be two new inflammable substances very like metals; but one of them lighter than ether, and infinitely combustible. So that there are two bodies decomposed, and two new elementary bodies found."
  • p. 115.
  • He had observed that although potash when dry is a nonconductor, it readily conducts when it becomes damp by exposure to air, and in this state "fuses and decomposes by strong electrical powers."
"A small piece of pure potash, which had been exposed for a few seconds to the atmosphere, so as to give conducting power to the surface was placed upon an insulated disc of platina, connected with the negative side of the battery of the power of 250 of 6 and 4, in a state of intense activity; and a platina wire communicating with the positive side was brought in contact with the upper surface of the alkali. ..."
"Under these circumstances a vivid action was soon observed to take place. The potash began to fuse at both its points of electrization. There was a violent effervescence at the upper surface; at the lower, or negative surface, there was no liberation of elastic fluid; but small globules having a high metallic lustre, and being precisely similar in visible characters to quicksilver appeared, some of which burnt with explosion and bright flame, as soon as they were formed, and others remained, and were merely tarnished, and finally covered by a white film which formed on their surfaces."
  • p. 117.
  • It is frequently stated that Davy was enabled to isolate the metals of the alkalis because of the large and powerful voltaic battery which he had at his disposal in the Royal Institution. This is not correct. The battery he employed was of very moderate dimensions, and not by any means extraordinary in power. It was the success he thus achieved that caused the large battery, which is probably referred to, to be constructed, by special subscription, in 1809.
    • p. 117 (footnote).
  • It would seem from his description of its properties that the potassium he obtained was most probably alloyed with sodium derived from impure potash. Potassium is solid up to 143° F.; but, as Davy subsequently found, an alloy of potassium and sodium is fluid at ordinary temperatures. ...When the potassium was exposed to air its metallic lustre was immediately destroyed, and it was ultimately wholly reconverted into potash by absorption of oxygen and moisture.
    • p. 118.
  • The "basis" of potash at 50° F. was a soft and malleable solid with the lustre of polished silver.
"At about the freezing point of water it becomes harder and brittle, and when broken in fragments, exhibits a crystallized texture, which in the microscope seems composed of beautiful facets of a perfect whiteness and high metallic splendour."
  • p. 119.
  • It may be converted into vapour at a temperature approaching a red-heat, and may be distilled unchanged; it is a perfect conductor of electricity and an excellent conductor of heat. Its most marked difference from the common run of metals was its extraordinarily low specific gravity.
    • p. 119.
  • Although no great stress can be laid on numbers so obtained, they serve to indicate that Davy had not yet obtained the pure metal.
    • p. 119.
  • The "basis" of soda is described as a white opaque substance of the lustre and general appearance of silver. It is soft and malleable, and is a good conductor of heat and electricity. Its specific gravity was found by flotation in a mixture of oil of sassafras and naphtha... It was found to fuse at about 180° F. (the real melting point of sodium is 197.5°). Its action on a number of substances—oxygen, hydrogen, water, etc.—is then described, and its general behaviour contrasted with that of the "basis" of potash.
    • pp. 119-120.
  • He then enters upon some general observations on the relations of the "bases" of potash and soda to other bodies.
"Should the bases of potash and soda be called metals? The greater number of philosophical persons to whom this question has been put, have answered in the affirmative. They agree with metals in opacity, lustre, malleability, conducting powers as to heat and electricity, and in their qualities of chemical combination." ...
"Potasium [sic] and sodium are the names by which I have ventured to call the new substances; and... these terms can scarcely express an error; for they may be considered as implying simply the metals produced from potash and soda. ...and though a name for the basis of soda might have been borrowed from the Greek, yet an analogous one could not have been applied to that of potash, for the ancients do not seem to have distinguished between the two alkalies."
  • pp. 120-121.
  • He begins by again drawing attention to the various surmises which had been made respecting the true nature of potassium and sodium. Although these substances had been isolated, and in the hands of chemists for upwards of two years, their properties were so extraordinary when compared with those of the metals in general, that many philosophers hesitated to consider them as true metals.
    • p. 131.

The Centenary of Davy's Discovery of the Metals of the Alkalis (1908)

by Thomas Edward Thorpe. A Discourse delivered before the Royal Institution, January 17, 1908. The Chemical News and Journal of Physical Science Vol. 97, No. 2527, pp. 210-211. (May 1, 1908)
  • The general properties and chemical activities of potassium and sodium are so very similar that as a matter of commercial production that metal which can be most economically obtained is necessarily the one most largely manufactured, and of the two that metal is sodium. To-day, sodium is made by thousands of tons, and by a process which in principle is identical with that by which it was first made by Davy, i.e., by the electrolysis of fused caustic soda.
  • [A]fter a series of revolutions in its manufacture, sodium, having been produced from time to time on a manufacturing scale by a variety of metallurgical methods involving purely thermal processes of reduction and distillation, entirely dissociated from electricity, we should have now got back to the very principle of the process which first brought the metal to light. 'And that this has been industrially possible is entirely owing to another of Davy's discoveries - possibly indeed the greatest of them all—Michael Faraday.
  • Before me, stretching down to the river, was the factory where a score of workers, clad in helmets and gauntlets and swathed like so many Knights Templar, travel-stained and war-worn, their visages lit up by the yellow soda flames, and their ears half-deafened with the sound of exploding hydrogen—a veritable inferno—were repeating on a Gargantuan scale the little experiment first made a century ago in the cellars of this building; turning out, day and night, hundredweights of the plastic metal in place of the little pin-heads which then burst upon the astonished and delighted gaze of Davy.

History of Chemistry (1909)

by Sir Edward Thorpe, Volume 1. From the Earliest Times to the Middle of the Nineteenth Century.
  • Even before the appearance of The Sceptical Chemist there was a growing conviction that the old hypotheses as to the essential nature of matter were inadequate and misleading. ...[T]he four "elements" of the Peripatetics had become merged into the tria prima—the "salt," "sulphur," and "mercury"—of the Paracelsians. As the phenomena of chemical action became better known... the conception of the tria prinui, as understood by Paracelsus and his followers, was incapable of being generalised into a theory of chemistry. Becher, while clinging to the conception of three primordial substances as making up all forms of matter, changed the qualities hitherto associated with them. According to the new theory, all matter was composed of a mercurial, a vitreous, and a combustible substance or principle, in varying proportions, depending upon the nature of the particular form of matter. When a body was burnt or a metal calcined, the combustible substance—the terra pinguis of Becher—escaped.
    • p. 70.
  • Other metals, like lead and mercury, did not appear to burn; but on heating them they gradually lost their metallic appearance, and became converted into calces. This operation was known as calcination. In the act of burning or of calcination phlogiston was expelled. Hence metals were essentially compound: they consisted of phlogiston and a calx, the nature of which determined the character of the metal. By adding phlogiston to a calx the metal was regenerated. Thus, on heating the calx of zinc or of lead with coal, or charcoal, or wood, metallic zinc or lead was again formed. When a candle burns, its phlogiston is transferred to the air; if burned in a limited supply of air, combustion ceases, because the air becomes saturated with phlogiston.
    • p. 72.
  • Some of the alchemists had discovered that a metal gained, not lost, weight by calcination. This was known as far back as the sixteenth century. It had been pointed out by Cardan and by Libavius. Sulzbach showed that such was the case with mercury. Boyle proved it in the case of tin, and Rey in that of lead. Moreover, as knowledge increased it became certain that Stahl's original conception of the principle of combustion as a ponderable substance he imagined, with Becher, that it was of the nature of an earth was not tenable. The later phlogistians were disposed to regard it as probably identical with hydrogen. But even hydrogen has weight, and facts seemed to require that phlogiston, if it existed at all, should be devoid of weight.
    • p. 85.

by James Campbell Brown

  • [T]he writings and labours of the alchemists were both extensive and important. ...[T]heir studies, although misdirected, were not... haphazard. The alchemists had a definite, and... logical, system of philosophy... [T]hey recognised—(1) the unity of matter; (2) the three principles—philosophical mercury, sulphur, and salt; (3) the four elementsfire, air, water, and earth; and (4) the seven metals—gold, silver, mercury, copper, iron, tin, and lead.
    • p. 129.
  • [W]hen an alchemist converted a metal into its oxide, or, as they expressed it, "made a calx" of it, he thought he had volatilised its mercury and fixed its sulphur. When he distilled ordinary mercury and found a solid residue in the alembic, he called it the "sulphur" of mercury; when he found a sublimed product in the receiver (mercury bichloride), he termed it the "mercury" of mercury or "corrosive sublimate."
    • p. 130.
  • The more logical mind of Artephius Longaevus introduced a modification of this theory. He distinguished two properties in a metal—the visible and the occult. The former, comprehending its colour, lustre, extension, and other properties visible to the eye, he called its "sulphur"; the latter, comprehending its fusibility, malleability, volatility, and other properties not visible until after... special treatment, he called its "mercury."
    • p. 130.
  • The mercury of a metal... represented its lustre, volatility, fusibility, and malleability; the sulphur of the metal, its colour, combustibility, affinity, and hardness.
    • p. 130.
Andrei Rublev, Trinity
  • The salt of the metal was merely a means of union between the mercury and the sulphur, just as the vital spirit in man unites soul and body. It was doubtless devised to impart a triple form to the idea, in conformity with the method of the theological schoolmen.
    • p. 130.
  • At a still later date [post-16th century] it was argued that exact and natural sciences proceed by induction and deduction, and occult and spiritual sciences by analogy. Following out this line of thought the alchemists produced the following remarkable trilogy:—
Material world Sulphur Mercury Salt
Human world Body Soul Spirit
Divine world Father Son Holy Ghost
...Each of these was a trinity in unity, and a unity in trinity. In each world was a distinct design,—in the material, the perfection of the metals; in the human, the perfection of the soul; in the divine, the contemplation of the Deity in His splendour.
  • p. 133.

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