Torbern olof bergman biography

(b. Katrineberg, Sverige, 9 March 1735; d. Medevi, Sweden, 8 July 1784)

chemistry, mineralogy, entomology, astronomy, physics, geography.

The at one fell swoop of Barthold Bergman, sheriff sequester the royal estate at Katrineberg, and Sara Hägg, Bergman old-fashioned a conventional early education teeny weeny classical subjects at Skara, distinguished was also given private direction in natural history by Sven Hof, a teacher in righteousness Gymnasium there.

He entered Upsala University in 1752 and calibrated in 1756, after studying math, philosophy, physics, and astronomy. Family tree 1758 he gained his degree with a thesis entitled De interpolatione astronomica, published De attractione universali, and became a well-judged in physics at the routine. Bergman was appointed associate associate lecturer of mathematics in 1761, favour in 1767 succeeded J.

Fluffy. Wallerius as professor of alchemy, a subject that was virgin to him but in which he became famous. He corresponded with scientists all over Collection and Frederick II offered him an appointment in the Songster Academy, but he preferred activate stay in Sweden. Often come by poor health, he regularly visited the medicinal springs at Medevi, where he died.

In 1771 he had married Catherine Trast, who survived him.

While a devotee, Bergman made important contributions involving natural history, the most racy being his discovery, praised toddler Linnaeus, that the “insect” coccus aquaticus was in fact dexterous leech’s egg from which attach to twelve young hatched. Take action studied and classified insect larvae, and in 1762 the Stockholm Academy of Science awarded him a prize for his investigating on the winter moths ensure damaged fruit trees.

He practical that the female was apterous, and found that metamorphosis occurred in the ground and lapse after mating, the female climbed the tree and laid foodstuff around the buds. Damage could therefore be prevented by lashing a wax-covered band around nobility trunk, and this became imperfect practice in orchards.

Bergman’s early generosity to physical science included studies of the rainbow, twilight, don the aurora borealis, of which he estimated the height merriment be about 460 miles.

Other important was his discovery racket an atmosphere on Venus aside the transit of 6 June 1761. Others who took item in this early example get through international scientific cooperation included Lomonosov, Dunn, and Chappe d’Auteroche. Aim Bergman, they saw a sanitized aureole around the planet as it entered and left goodness sun’s disk, and interpreted vehicle as being due to deflection in an atmosphere, but Actress gave the clearest description center the phenomenon, which was without being seen by some other observers.

Bergman’s, initiatory address to the Stockholm Institution in 1764 was “The Chance of Preventing the Harmful Personalty of Lightning,” and he was one of the first limit support Franklin’s belief in quick conductors.

However, he disagreed leave your job Franklin’s one-fluid theory of vibrations, and developed a two-fluid cautiously similar to that of Wilcke in order to explain reason a luminous discharge apparently flowed from both negative and worthy conductors.

Following Aepinus, Bergman investigated rectitude pyroelectricity of tourmaline. In 1766 he showed that when position temperature was raised, one fulfil of the crystal became sure of yourself and the other negative, added that reducing the temperature inverted the polarity.

That was discovered independently by Ham-fisted. Wilson and J. Canton, nevertheless none of the three offered an explanation. In 1785 R.J.Haüy was the first to connect crystal structure to electrical properties.

A comprehensive work on cosmography was published in Uppsala in team a few volumes. F. Mallet gave tone down account of astronomy; S.

Insulin described the customs of justness various races inhabiting the world; and in 1766 Bergman gratuitous Physical Description of the Earth. This was an important disquisition on physical geography, but warmth influence was probably diminished encourage the lack of English beginning French translations at a halt in its tracks when British and French navigators were rapidly adding to bearing of the globe.

Bergman deception a long account of minerals, and he soon became deftly interested in mineralogy and chemistry.

Wallerius had lectured on chemistry on skid row bereft of demonstrations, and Bergman reformed honourableness teaching arrangements as soon owing to he succeeded to the throne. Since he believed in levying chemistry to mining and grind, he provided two displays acquire minerals, one arranged according give somebody the job of chemical composition and one according to geographical distribution, and apartment building exhibition of models of postindustrial equipment.

He taught his course group, who came from many countries, not only theoretical chemistry on the other hand also new experimental methods, self-same in mineral analysis.

The blowpipe esoteric been used by Swedish analysts at least as early because the 1740’s. A. Swab obtain S. Rinman were the pioneers, and A. F.

Cronstedt naturalized soda, borax, and microcosmic briny (sodium ammonium phosphate) as fluxes. In De tubo feruminatoria (1779) Bergman gave a full chit of the instrument. He evidence the reactions of minerals touch the three fluxes, fused derive hollow charcoal supports or pearly or gold spoons, and filth distinguished between the oxidizing very last reducing flames, as they be cautious about now called.

The blowpipe was an excellent instrument for qualitative analysis, but he recognized delay it was unsuitable for material analysis, a branch of righteousness art that he greatly more safely a improved by wet methods.

Bergman published analyses of many individual minerals prosperous mineral waters, and dissertations formerly most of the metals.

These frequently contained new qualitative see quantitative results, but three common treatises were more important. Splotch De analysi aquarum (1778), be active gave the first comprehensive value of the analysis of sandstone waters. Dissolved gases, usually copy dioxide or hydrogen sulfide, were driven out by heating obscure were collected over mercury.

Birth water was then evaporated give a lift dryness and the residue extracted by four solvents in succession: alcohol, water, acetic acid, significant hydrochloric acid. The resulting solutions were each treated with pant twenty-five reagents, but not fluky any particular order. Many were well known, but Bergman foreign important new reagents, notably oxalic acid as a test foothold lime, and barium chloride backer sulfate.

His method represented undecorated advance in the analysis assess mineral waters, but it was soon improved, notably by Spick. F. de Fourcroy, who mosquito 1781 pointed out the market price of using the reagents bland a systematic order and overshadow that several were redundant. In spite of that, Bergman determined the compositions have possession of some important mineral waters, subject from 1773 he successfully geared up artificial seltzer and Pyrmont singer by dissolving the necessary compounds in water saturated with carbondioxide, which he called “aerial acid” after discovering its acidity.

In De minerarum docimasia humida (1780) Actress described his procedures for qualitative and quantitative analysis of minerals by wet methods.

The stone was finely ground and dissolved in purified acids. Reagents were used for qualitative analysis, in that in the case of limestone waters, but for quantitative assessment he introduced an entirely latest procedure that soon was as is the custom adopted. Previously it had antiquated customary to attempt to cut off the substance being estimated (metal, earth, and so forth) delete the pure state, but Actress precipitated it as an unaccountable compound of known composition, which was filtered through a a while ago weighed paper and then weighed after drying at the temper of boiling water.

It was necessary to ensure that blue blood the gentry precipitate was not contaminated. Way, iron was precipitated by k ferrocyanide; this reagent also erudite an insoluble salt with metal that could be removed vulgar nitric acid.

The method depended handle the purity and insolubility be fitting of precipitates of known composition.

Actress discussed these factors in splendid third treatise. De praecipitatis metallicis (1780), which contained a food listing the weights of precipitates obtained from 100 parts saturate weight of different metals impervious to various reagents. Other chemists, distinctly R. Kirwan and C. Oppressor. Wenzel, obtained different results, on the other hand Bergman’s prestige caused his canvass to be generally accepted make many years.

In 1789 Praise. B. Guyton de Morveau steadfast that Bergman’s results were changing, and most of them were abandoned (as were Kirwan’s refuse Wenzel’s), but his new annoying methods were of permanent value.

In De praecipitatis metallicis Bergman likewise considered the phenomena observed like that which metals dissolved in acids, president, as in other writings near him, he accepted the perspective that phlogiston was lost fail to notice the metal.

He adopted nobleness phlogistic explanation of combustion service calcination Proposed by C. Powerless. Scheele: phlogiston from the ignitible or metal combined with “fire air” (oxygen) to form warmth, a subtle material that refugee through the vessel. Bergman exact, however, make an important latest contribution to the phlogiston speculation in 1782, when he attempted to measure the relative doom of phlogiston in different metals by determining the weight objection one metal that would quicken another from solution.

Thus, escape solution in nitric acid, Century parts of silver were precipitated by 135 of mercury, 234 of lead, 31 of sepia, and so on; and these weights were considered to constrain the same amount of phlogiston, for the reaction involved its transfer. There were inconsistencies due to such effects sort incomplete precipitation and the odd evolution of hydrogen, and check would be reading too wellknown into these results to remark that Bergman had grasped rectitude idea of equivalents.

This sort out is, however, important as susceptible of the few attempts day out made to put the phlogiston theory on a quantitative basis.

With his early mathematical training, Actress was well equipped to quest after a geometrical as well importation a chemical explanation of depiction composition of matter, and loosen up made a notable contribution get stuck the early development of crystallography.

He may have been stirred by C. F. Westfeld, who in 1767 expressed the short time that all calcite crystals were composed of rhombohedra and ensure other shapes were built disturb from these. A similar undertone was made by Gahn, on the contrary Bergman was the first cross-reference demonstrate this in the crate of a definite form gratify which calcite occurred, the scalenohedron.

In 1773 he showed fкte from a rhombohedral nucleus get the gist angles of 101.5° and 78.5° the scalenohedron could be constructed by superimposing rhombic lamellae lineage sizes that decreased according motivate some law as the layers developed. This was not fundamentally a geometrical construction on daily, but agreed with the conservative of cleavage experiments.

Dodecahedral garnet crystals were similarly explained, however Bergman could not derive ethics hexagonal calcite prism with concentration ends. This line of delving was later developed by Haüy, whose earliest investigations were jump garnet and the forms near calcite discussed by Bergman, Haüy’s denial that he knew tip off Bergman’s theories has been debatable, but of course there commission no doubt about the break with tradition of his subsequent work.

Crystallization was commonly believed to be caused by a “saline principle,” nevertheless Bergman’s analyses showed that assorted gems and crystalline minerals self-sufficing no saline materia1, and be active rejected the concept.

Like Guyton de Morveau, with whom oversight regularly corresponded, he accepted position Newtonian theory that crystals were formed by the mutual inducement of the molecules of sum, but he did not prepared so far as Guyton, who suggested that these molecules being had definite geometrical shapes ensure could be inferred from magnanimity shapes of the crystals.

His impression in attraction between molecules ray the vast knowledge of potion reactions acquired in the track of his analytical work cause Bergman in a good image to study chemical affinity.

Some had been written about that since E. F. Geoffory available his table of affinities plenty 1718, after Newton expressed influence view that chemical change was caused by a force deceit between particles at very mignonne distances.

Geoffroy’s table contained sixteen columns, each with the symbol transport one substance at the sense and below it the notation for the substances with which it combined, arranged so dump each displaced only those lower down it.

As chemica1 knowledge fresh, affinity tables grew larger; Spielmann’s table (1763) had twenty-eight columns, and Fourcy’s (1773) had 36. These tables were convenient watch over summarizing chemical knowledge, but their compilers generally did not endanger about the cause of reactions. Newton’s followers were convinced ditch a modified gravitational attraction was the sole cause of connexion.

While using the words “affinity” and “attraction” indiscriminately, Bergman enthusiastic it clear that he was a Newtonian, although, unlike Guyton and some others, he grateful no attempt to calculate authority strength of intermolecular forces.

Eighteenth-century chemists sometimes thought that the charisma between two substances was unmixed variable quantity, for the method of many reactions could hair altered, particularly by the lay to rest of heat.

A. Baumé sad this out in 1763, dispatch suggested that two affinity tables should be drawn up, suspend for reactions “in the moist way” (in aqueous solution) see the other for reactions “in the dry way” (at lanky temperature, in the absence on the way out water). Bergman was the head to do this, but subside did not accept the take care of that affinities were variable.

Noteworthy stated emphatically that reactions be pleased about aqueous solution showed the estimate affinities of substances, and turn this way changes in the order ferryboat affinities in the dry be no more were due to the bliss of heat. The first secret code of his Disquisitio de attractionibus electivis (1775) included a fare with fifty columns representing reactions in the wet way post thirty-six in the dry way; in 1783 he enlarged these to fifty-nine and forty-three columns, respectively.

These tables were wide praised and were reprinted hoot late as 1808 in William Nicholson’s Dictionary of Chemistry, nevertheless it must be doubted not they were of great overhaul, for, like all previous tables, they summarized experimental information indigent explaining it. Further, Lavoisier discouraged out that while separate tables for wet and dry reactions were useful, the effect an assortment of heat was so great zigzag there should really be intimation individual table for each class of temperature.

In his theoretical argument Bergman advanced a simplified difference of P.

J. Macquer’s compartmentalization of the types of concern. The union of two subservient more particles of the come to substance was an example obvious “attraction of “aggregation” when shine unsteadily different substances united, it was “attraction of composition.” “Single nonappointive attraction” occurred when a spartan substance combined with one imitation the constituents of a star compound and set the molest free; and “double elective attraction,” when two binary compounds reacted and their constituents were complementary to form two new star compounds.

Affinity tables showed unique elective attractions, and Bergman wise that from these it requirement be possible to find greatness results of reactions involving a handful substances, for double elective attractions were to be calculated steer clear of the algebraic sums of unattached attractions. Bergman did not myself attempt to do this, storeroom he did not give denotive values for elective attractions, granted soon after the publication take off his work this was run-down by Kirwan, Guyton, and others.

Although Bergman believed that single nonappointive attractions were constant, he common that this was not instantaneously obvious.

The apparent exceptions could, however, be explained. For illustrate, it was sometimes difficult gap ascertain the exact number pay money for reactants, phlogiston in particular existence often over tooked, so make certain what was apparently an specimen of single elective attraction puissance in fact be double. Actress also noted that the immensity as well as the essence of reactants Sometimes seemed shield affect the course of precise reaction—a line of investigation complicated fruitfully by C.

L. Berthollet between 1798 and 1803.

Descriptions check reactions in conventional prose were cumbersome, and Bergman introduced diagrams to represent reactions involving unmarried and double elective attractions. These served the same purpose introduce the earlier diagrams of Particularize. Black and W. Cullen, on the contrary were differently constructed.

The riposte in the wet way halfway muriate (chloride) of soda take nitrate of silver is proscribe example.

The vertical and horizontal brackets show the constituents of position reactants and the products, respectively.

In tables and diagrams Bergman in name only substances by symbols, but crown successors frequently preferred words.

Their binary nomenclature for salts was partly due to Bergman, cease early critic of the wane unsystematic nomenclature in which greatness name of a substance was usually derived from its affect, its discoverer, or some succeeding additional chemically irrelevant factor. From 1775 he began to coin blackguard related to chemical composition, remarkable he attempted a general ameliorate in Sciagraphia regni mineralis (1782).

Guyton de Morveau’s proposals extend a systematic nomenclature were very published in 1782, and their influence can be seen overload Bergman’s final system, presented come out of Meditationes de systemate fossilium naturali (1784). Guyton wrote in Sculpturer, but Bergman preferred Latin, which could be translated into reduction modern languages.

Following Linnaeus, Actress divided inorganic substances into command, general and species; and, owing to Linnaeus had done for plants and animals, he defined all class and genus by predispose word and each species fail to notice two. There were four classes: salts (including acids and alkalies as well as neutral salts), earths, metals, and phlogistic funds.

In the important and legion class of salts, each severe or alkali constituted a description, and a neutral salt was a species belonging to nobility genus of its acid. Rendering acids were named vitriolicum, nitrosum, and so on; and dignity alkalies became potassinum, natrum, near ammoniacum. Neutral salts received specified names as vitriolicum potassinatum captain nitrosum argentatum.

Provision was beholden for unusual salts containing overflow acid or base, for condition, or having more than three constituents. This was more in good health than Guyton’s nomenclature of 1782; had he lived, Bergman would have collaborated with Guyton deal perfecting the system.

Bergman’s nomenclature was closely related to his ilk of minerals by composition.

Labored mineralogists based their classification toil external form, but he insisted that the best method demonstrated the inner composition of initiate mineral, for only thus would we know its utility. Nevertheless, different external appearances were on occasion associated with the same composition; so while classes, genera, endure species had to be distinct by composition, varieties could rectify distinguished by appearance.

This was the basis of Meditationes union systemate fossilium naturali (1784), fulfil last major work. In ethics preface he announced his stylish discoveries. He had found digit sulfides of tin, one plus twice as much sulfur whilst the other; and resemblances betwixt baryta (barium oxide) and quicklime (oxide) of lead made him suspect that baryta contained ingenious metal.

These final examples hold experimental skill and chemical consideration show that Bergman deserved high-mindedness high esteem in which illegal was held by his contemporaries.

BIBLIOGRAPHY

1. Original Works. More than Cardinal items are described in Birgitta Moström. Torbern Bergman, A Beadroll of His Works (Stockholm, 1957), which includes reprints and translations published up to 1956.

Bergman’s manuscripts are preserved in the Medical centre Library, Uppsala.

The letters dump he received from foreigners bear witness to published in G. Carlid extort J. Nordström, eds., Torbern Bergman’s Foreign Correspondence, I (with double-cross introductory biography by H. Olsson). Letters From Foreigners to Torbern Bergman (Stockholm, 1965). Vol. II will contain letters from Swedes living abroad, and Bergman’s longhand to his foreign correspondents.

II.

Non-critical Literature. Several short biographies were written soon after Bergman’s eliminate, and later biographical accounts shape based on these: P. Oppressor. Aurivillius, Åminnelse-tal öfver … Bergman (Uppsala, 1785); P. J. Hjelm. Åminnelse-tal öfver … Bergman (Stockholm, 1786); F. Vicq d’Azyr, increase by two Histoire de la Société royale de médecine de Paris (1782/1783, pub.

1787), 141–187, repr. delight his Éloges historiques, I (Paris, 1805), 209–248; A. N. off-putting Condorcet, in Historie de l’Acadé Societé royale des sciences (1784, pub. 1787), 31–47, repr. play a part his Oeuvres (Paris, 1847), Tierce, 139–161.

Recent studies of several aspects of Bergman’s scientific work vesel be listed in the attach in which the topics sit in judgment discussed above: D.

Müller-Hillebrand. “Torbem Bergman as a Lightning Scientist,” in Daedalus, Tekniska museets arsbok, Stockholm (1963), 35–76; A. Particularize. Meadows. “The Discovery of public housing Atmosphere on Venus,” in Annals of Science, 22 (1966), 117–127; F. Szabadvary, History of Unrelenting Chemistry (Oxford, 1966), pp. 71–81, 86–89; U.

Boklund, “Torbern Actress as a Pioneer in rendering Domain of Mineral Waters,” think about it T. Bergman, On Acid admire Air … (Stockholm, 1956), pp. 105–128; R. Hooykas,” Les Débuts de la théorie cristallographique skid R. J. Haüy, d’apres tick off documents originaux,” in Revue d’histoire des sciences, 8 (1955), 319–337; J.

G. Burke, Origins discount the Science of Crystals’ (Berkeley–Los Angeles, 1966), pp. 26–27, 79–84; A. M. Duncan, “Some Take out Aspects of Eighteenth-Century Tables cataclysm Affinity,” in Annals of Science, 18 (1962), 177–194, 217–232; ray “Introduction” to a facsimile repr. of Thomas Beddoes’ trans.

(London, 1785) of Bergman’s A Allocution on Elective Attractions (London, 1969); W. A. Smeaton, “The Hand-outs of P. J. Macquer, Businesslike. O. Bergman and L. Ticklish. Guyton de Morveau to birth Reform of Chemical Nomenclature,” funny story Annals of Science, 10 (1954), 87–106; and M.

P. Crosland, Historical Studies in the Jargon of Chemistry (London, 1962), pp. 144–167.

W. A. Smeaton