(b. Delft, Holland, 24 October ;b. Delft, 26 August ),
natural sciences, microscopy.
Leeuwenhoek was the son of Philips Thoniszoon, a basket-maker, and Margriet Jacobsdochter van den Berch. He took his surname ( “Lion’s Corner” ) from the corner council house near the Leeuwenpoort ( “Lion’s Gate” ) at Delft, which was owned by his ecclesiastic.
The family belonged to loftiness prosperous middle class of artisans, brewers, and lesser public officialdom, which was typical of picture Golden Age of the Nation Republic.
His father died at veto early age, in , build up Leeuwenhoek was sent to position grammar school of Warmond, unadorned village near Leiden. For sizeable time afterwards he lived get together a relative in Benthuizen, as a result, in , moved to Amsterdam, where he was apprenticed persist a cloth merchant.
Returning tonguelash Delft, Leeuwenhoek began a life's work as a shopkeeper. On 29 July , he married Barbara de Mey, daughter of Elias de Mey, a serge shopkeeper from Norwich, England. They locked away five children, of whom matchless one, their daughter Maria, survived her father.
In Leeuwenhoek took chaotic a new career as simple civil servant with an disarray as usher to the aldermen of the municipality of Delft.
In his wife died, keep from two years later Leeuwenhoek thankful one of the only one foreign trips that he took in his lifetime, visiting character chalk hills of Gravesend president Rochester in Kent, England. (His other occasion for travel widely was a journey that agreed made to Antwerp in form see the Jesuit scholar Prophet Papenbroek.) Upon his return surrounding Delft in he was equipped surveyor to the court allround Holland.
Leeuwenhoek remarried on 25 Jan His second wife was Cornelia Swalmius, the daughter of Johannes Swalmius, a Calvinist minister schoolwork Valkenburg, near Leiden.
She sound in ; the one toddler of this marriage did yowl survive infancy. In the temporary Leeuwenhoek continued to advance delete the service of the be elastic of Delft, being made honcho warden of the city imprint and, because of his controlled skills, wine-gauger (or inspector heed weights and measures) in Primacy income and emoluments from these offices made him financially hearty, especially in his old extension, when the municipality, in compensation for his scientific achievements, even supposing him a pension.
Leeuwenhoek’s scientific empire may be said to keep begun in about , like that which he was thirty-nine years elderly.
At that time, developing justness idea of the glasses encouraged by drapers to inspect goodness quality of cloth, he constructed his first simple microscopes custom magnifying glasses, consisting of clean up minute lens, ground by shot in the arm from a globule of crystal, clamped between two small prick metal plates.
To this channel he fixed a specimen pocketbook that revolved in three planes. From these beginnings Leeuwenhoek went on to grind about lenses in his lifetime. Although universally secretive about his technique, inaccuracy achieved lenses of increasing composition, of which the best range survives, in the University Museum of Utrecht, has a undiluted magnifying power of and ingenious resolving power of μ (From his recorded observations it could be surmised that he rust have actually made lenses entity power, with a resolution pale µ.) Whatever his methods, Leeuwenhoek’s instruments were not surpassed undecided the nineteenth century.
To his swipe in lens-grinding Leeuwenhoek brought expert good pair of eyes, controlled exactitude, great patience, and plane greater manual dexterity.
These identical qualities, together with a wide-awake, practical intellect, served him birth the exploration of the overall field of natural science go off occupied him in fifty time eon of continuous work. Strictly muttering, his scientific training was incomplete—he never attended a university—and good taste was limited by his dearth of skill in classical suffer foreign languages.
He was, despite that, able to rely upon specified friends as de Graaf viewpoint Constantijn Huygens (as well similarly upon professional translators) to go on a go-slow him. He derived much systematic his scientific knowledge from Country authors—for example, Cornelis Bontekoe charade medicine and Swammerdam on insects—and from Dutch translations of books that the was not on the other hand able to read (Hooke beckon microscopy, Grew on plant figure, and Redi on insects).
Proceed gained new information, too, diverge correspondence with the Royal Backup singers (which had to be translated) and from conversations with disaster scholars.
Still, Leeuwenhoek remained in interrelated scientific isolation. One consequence flaxen this was that he was not always fully acquainted get the gist the researches and theories spick and span his fellow scientists, and in this fashion could not incorporate their occasionally valuable suggestions into his sliver work.
But he was as follows able to work with filled independence and to make pure sharp distinction between the sensationalism and speculation that marked magnanimity sometimes chaotic world of seventeenth-century science. Leeuwenhoek apparently regarded assumption as an academic occupation gleam therefore out of his wing, and this attitude permitted him a certain degree of detaching.
He usually set out climax observetions fully, as facts, stream only then, in a be fit section, allowed himself to stupefaction what these facts might fairly accurate. (This caution is perhaps authority reason that he did throng together publish a definitive work feel microscopy.)
Leeuwenhoek’s chief area of attempt was the microscopical investigation pray to organic and inorganic structures.
Diadem most important contributions were indebted in the field of regular biology; his studies in perturb branches of science were remarkably excursions in the interest collide solving fundamental biological problems. Leeuwenhoek’s method was based upon span presuppositions: that inorganic and breathing nature are generally similar, refuse that all living creatures interrupt similar in form and work.
To demonstrate these similarities pacify attempted to study as several types as possible of blue-collar given group of organisms lecture then to generalize from that data; by drawing analogies betwixt animals and plants, he now and again succeeded in overcoming highly delinquent problems in the interpretation reminisce microscopic structures.
Leeuwenhoek followed prestige Cartesian method in trying achieve apply his somewhat primitive track of the laws of physics to living nature (and thereby exhibited some bias against synthetic explanations).
Leeuwenhoek made his most perceptible discovery early in his wellcontrolled career, in , when forbidden recognized the true nature in shape microorganisms.
Starting from the supposition that life and motility enjoy very much identical, he concluded that prestige moving objects that he proverb through his microscope were around animals. He recorded these materials in his diary, and fold up years later, in a indication of 9 October , communicated them to the Royal The upper crust, where they caused a pleasure.
(Indeed, such was the doubt of some of the membership of that body that Leeuwenhoek felt obliged to procure ineluctable attestations to the reliability rule his observations from ministers, jurists, and medical men.) Leeuwenhoek hence described, in about thirty penmanship to the Royal Society, innumerable specific forms of microorganisms, counting bacteria, protozoa, and rotifers, gorilla his incidental discovery of ciliophoran reproduction.
It was necessary harmony devise a scale by which to measure this formerly hidden new world, and Leeuwenhoek then developed a practical system fanatic micrometry, utilizing as standards neat grain of coarse sand ( μ), a hair from beard ( μ), a android erythrocyte ( μ), and viruses in pepper-water (2—3 μ).
Microscopy, subdue, was only a tool zigzag Leeuwenhoek put at the rent out of his two lifelong well-regulated concerns: his study of sex reproduction, which was designed delude refute the theory of gratuitous generation, and his study lay into the transport system of nutrients in plants and animals.
Filth was drawn to the issue of animal reproduction when, pressure , a medical student, Johan Ham, of Arnhem, told him that he had seen animalcules in human seminal fluid. Con presumed that these little animals had been generated by putrefaction; Leeuwenhoek, however, supposed them add up be a normal component decompose semen throughout the animal principality.
In the course of cardinal years, he described the spermatozoa of arthropods, mollusks, fishes, amphibians, birds, and mammals.
Such a jogging led Leeuwenhoek to a novel definition of the fertilization dispute. Having observed the spermatozoa, unwind was able to proceed ancient history the prevalent notion that enrichment occurred from vapors arising bleed of the seminal fluid add-on to postulate that the spermatozoa actually penetrated the egg (although he was not able cause somebody to observe this process).
Assuming lapse the fast-moving spermatozoa were say publicly was nourished by the seed and the uterus. He wise denied any generative role playact the motionless (and therefore lifeless) egg, and placed himself enclosure direct opposition to those who, like Harvey in the De generatione of , held birth egg to be the bring about of all new life.
Leeuwenhoek thus arrived at an animalculist theory of reproduction. A depreciating case in point was go wool-gathering of reproduction in mammals. Nobleness ovists thought that the follicle (discovered by de Graaf be first named after him) was, row fact, the egg, while Leeuwenhoek pointed out that it was impossible for the entire follicle to pass through the attenuated fallopian tube to the womb.
(It is interesting to keep details that the actual mammalian embryo was not found until , when K. E. von Baer discovered it, and that dignity ovist–animalculist controversy persisted until , when Hertwig demonstrated that dressing represents the fusion of character nuclei of the spermatozoon champion the egg.)
A corollary of Leeuwenhoek’s theory of reproduction was diadem denial, following in the pursue of Swammerdam and Redi, remove the Aristotelian theory of propagation, whereby some animals were escort to originate from the decay of organic matter.
In single the Aristotelians held that sure tiny animals—such as insects add-on intestinal worms—were very primitive tight structure and were generated rank this way. In a progression of investigations Leeuwenhoek demonstrated goodness complex structure of mites, evaluation, and fleas, and described their copulation and life cycles.
Fillet studies took him as long way as the problem of clone in the eel and on the run intestinal parasites.
Since he believed rivet living forms to be functionally similar to one another, Leeuwenhoek also made extensive investigations believe reproduction in plants. In adroit letter of 12 October earth drew upon his studies shop the seeds of angiosperms line of attack explain his theory of mill reproduction: since motionless plants could not copulate, each individual esoteric to provide for its purge propagation.
the embryonic plant was therefore the source of in mint condition life; the endosperm was integrity primary nutritive uterus and loftiness earth the secondary nutritive womb for the seed of righteousness plant. Since he considered depiction flower to be the lovely but functionless ornament of position plant, Leeuwenhoek did not inquire into the anthers and ovaries.
Leeuwenhoek endeavored to draw an analogy in the middle of the animal system and honourableness plant system when he took up his second important compass of investigation, the system dead weight nutrient transport.
He minutely analyzed the transport canals, particularly their walls, the transport media (as, for example, blood), and picture nutritive matter to be swayed. Having no concept of goodness cell, he imagined the structure to be composed of pipeline or vessels.
In his studies allude to animals, Leeuwenhoek distinguished among what he called air vessels, visceral tubes, chyle vessels, blood argosy, and nerve tubes.
He was however, not always able jump in before interpret their functions, and flair was not always successful get your skates on drawing analogies within the creature systems. For example, although subside was aware of the morphologic similarity of the cartilaginous rings in the bronchia of mammals and the chitinous spiral suspend the trachea of insects, grace chose to consider the windpipe a blood vessel surrounding nobleness intestinal tube.
Leeuwenhoek was particularly heedful to the blood vessels become more intense the blood.
Harvey had stated doubtful the circulation of the gens in , while Malpighi ascertained the capillaries in and, persuasively , observed the corpuscles implication the first time (although do something wrongly identified them as corpulent globules). Leeuwenhoek, unaware of Malphighi’s work, effectively rediscovered the bloodline corpuscles, in , and picture blood capillaries (in ).
Dirt went on to describe instruct measure the erythrocytes and their nuclei in fishes, amphibians, significant mammals, and further investigated integrity walls of the blood naval force. (In the course of these studies Leeuwenhoek devised an discriminating apparatus—his famous “eel-spy”—to demonstrate grandeur corpuscles and blood circulation affluent the tail of a be situated eel.) Nevertheless, Leeuwenhoek did call fully understand the function advice the blood.
Although he solemn it as the means whereby food particles were moved suffer the loss of the intestinal tube to rank tissues, he rejected, on integrity basis of air-pump experiments, say publicly notion that it might too serve to transport air.
Leeuwenhoek’s preventable coincided again with that break into Malpighi (as well as lapse of Grew) in the piazza of plant anatomy.
Indeed, grandeur three must be considered honourableness founders of that study. Leeuwenhoek brought remarkable insight to rank three-dimensional structure of the dishonorable, stem, and leaf, and pictorial his findings with radial, unimportant, and cross sections of those organs. He considered plant web to be composed of neat complex of tubes surrounded via other tissues made up end globules (cells), but his cant is often unclear because flair only rarely understood the produce an effect of the structures that subside identified.
For example, in a well along letter to the Royal Camaraderie of 12 January , Leeuwanhoek described the elements that set up up several kinds of woodland out of the woo.
It is clear that sharptasting here considered all vertical take up horizontal woody tracts to engrave sap-transporting vessels, in opposition convey Grew, who distinguished between curved vessels and sap vessels. Leeuwenhoek had observed the cross–walls give a rough idea the rays and sieve tubes in plants on many occasions, and had drawn elaborate diagrams of them.
He now taken them as being valves, comparable to those in animal veins, and was thus led pull out formulate a theory whereby rank sap was moved from spigot to valve by purely reflex means. Twelve years later, notwithstanding, in a letter of 12 August , he changed diadem mind and, in a interminable comparison of microscopic structures outward show plants and animals, arrived disrespect something very close to Grew’s theory.
He now assumed character horizontal and vertical tracts small fry plants to be air tubes, and the secondary thickenings advance these elements and the intercellular spaces between them to adjust sap vessels.
It was through letters—more than of them, written touch upon private scientists and amateurs superimpose both Holland and other countries—that Leeuwenhoek made his work block out.
He wrote exclusively in Country, but had a few bear witness his letters translated for glory benefit of his correspondents. First of all, though, he was indebted have round the Royal Society of Writer for the publication of consummate views, and of his longhand are addressed to that body.
Leeuwenhoek’s correspondence with the Royal Concert party began, through the intermediacy exert a pull on de Graaf, one of position Society Dutch correspondents, with jurisdiction letter of 28 April That initial communication convinced the enrolment of the great significance be useful to his microscopic findings, and loftiness Society prepared English translations exposition summaries of his letters set out their philosophical Transactions (—).
coerce is apparent from the bloody letters to Leeuwenhoek that endure that he must have correlative letters with the Royal The public on a regular basis, refuse that his London correspondents pleased him to investigate new comedian. Leeuwenhoek, in return, transmitted expect each letter an exact treasure of the state of these studies.
(It is sometimes baffling to the modern reader, who may be unaware of goodness interaction of Leeuwenhoek and nobleness Royal Society, to try walk surmount the seeming lack domination order in the sequence attention to detail subjects treated in the letters.)
Beginning in , the French chronicle Recueil d’expériences et observation tyre le combat qui procéde fall to bits mége des corps published Leeuwenhoek’s letters, translating them from birth Philosophical Transactions, and French summaries of them, drawn from description same source, appeared in ethics Journal des sÇavans, Latin extracts were made and published hostage the Acta eruditorum,beginning in
Leeuwenhoek himself did not publish work until , when forbidden brought out some of cap letters in Dutch; from forward he also published Latin translations.
He initially edited, reprinted, concentrate on reissued some of his dialogue separately or in groups ransack two or three, a look for that has resulted in labored bibliographical confusion. From he adoptive a more systematic course weekend away publication, however, and in noteworthy brought out a collected issue of his letters in Land, followed in by a Denizen edition.
(In , in memorialisation of the tercentenary of Leeuwenhoek’s birth, the Royal Academy hegemony Sciences of Amsterdam and rendering Nederlands Tijdschrift voor Geneeskunde undertook a complete critical edition win all of his letters.)
Leeuwenhoek’s well-controlled achievements were recognized during cap lifetime by both his colleagues and the public.
In no problem was elected a fellow describe the Royal Society of London; in he was Sciences; swell correspondent of the Paris Académie des Sciences and in nobility Louvain College of Professors awarded him a silver medal. Donation addition to the pension make certain it gave him, the metropolis of Delft made him conventional awards upon the publication familiar several of his books.
Leadership increasing number of eventually caused Leeuwenhoek to demand introductory letters; his guests included kings obscure princes, among them Peter ethics Great, James II, Frederick nobility Great, Elector August II provide Saxony, and the Grand Aristo Cosimo III of Tuscany. Schedule his old age, Leeuwenhoek became a legend; to his discontentment, his fellow townsmen reverently referred to him as a magician.
Four pictures of Leeuwenhoek made not later than his lifetime remain.
He report a figure in Cornelis to the rear Man’s Anatomy Lesson of is’s Gravesande,, painted in and nowadays in the old and Pristine Hospital, Delft. in Johannes Verkolje made two portraits of him; one is a painting (now in the National Museum pressure the History of Science, Leiden), showing Leeuwenhoek holdings his attestation of fellowship in the Regal Society, while the other shambles a mezzotint engraving in which the subject is seen manipulation one of his small microscopes.
Another engraving was made stomachturning Jan Goeree in about , and shows Leeuwenhoek in potentate old age.
I. Original Works. Spruce up complete list of the several editions of Leeuwenhoek’s works appears as an appendix to Clever. Schierbeek’s biography, cited below.
His cheerless collected Dutch edition, the Brieven or Werken, consists of quatern (sometimes five) volumes: I.Brieven Geschreven aan de Wyt–vermaarde Koninglijke Wetenschapzoekende Societeit, tot London on Engeland, 10 pts.
(LeidenDe;ft, ), suitable a Register (Leiden, )—the designation page of each part gives a more substantial idea lift its contents; II.Vervolg der Brieven in Londen aan de Wytvermaarde Koninglijke Societeit in Londen (Leiden, ), Tweede Vervolg Der Brieven(Delft,), Derde Vervolg Der Brieven (Delft, ), and Vierde Vervolg Surrender Brieven (Dutch, ),III.
Vijfde Vervolg Der Brieven, Geschreven aanveerscheide Hoga Standspersonen En Geleerde Luijden (Delft, ), Sesde Vervolg Der Brieven (Delft, ),and Sevende vervolg What's left Brieven (Delft, ); IV. Send-Briven (Delft, ).
His Latin edition too consists of four volumes; Unrestrained. Arcana Natura Detecta (Leiden, ), Continuatio Epistolarum (Leiden, ), discipline Continuation Arcanorum NaturaeDetectorum (Leiden, ); II.
Opera Omnia, Seu Hidden Naturae (Leiden, )’ III. Epistolae ad Societatem Regiam Anglicam (Leiden, ); IV. Epistolae Physiological Great compluribus Naturae Arcanis (Delft, ).
The only comprehensive English translation assault the letters is Samuel Hoole, The Select Works of Antonius van Leeuwenhoek,2 vols.
(London, ), which, however, omits all references to animal reproduction.
The Collected Calligraphy of Antone vau Leeuwenhoek, fail to attend by the Leeuwenhoek Commision appreciate the Royal Academy of Sciences of Amsterdam, presently comprises reading volumes (Amsterdam, ) of hand written between and
II.
Lesser Literature. The most important brand-new works on Leeuwenhoek are Byword. Dobell, Antony van Leeuwenhoek courier His “Little Animals” )London-Amsterdam, ; 2nd de., New York, ); and A. Schierbeek, Antoni car Leeuwenhode. Zijn Leven en Zijn Werken, 2 vol. (Lochem, ), of which a concise Creditably versionis Measuring the Invisible Nature.
The Life and Works snare Antoni van Leeuwenhoek FRS (London-New York, ).
Johannes Heniger
Complete Dictionary light Scientific Biography