Friday 16 March 2018

Antonie van Leeuwenhoek
Anthonie van Leeuwenhoek (1632-1723). Natuurkundige te Delft Rijksmuseum SK-A-957.jpeg
A portrait of Antonie van Leeuwenhoek (1632–1723) by Jan Verkolje
Born (1632-10-24)24 October 1632
Delft, Dutch Republic
Died 26 August 1723(1723-08-26) (aged 90)
Delft, Dutch Republic
Nationality Dutch
Known for The first acknowledged microscopist and microbiologist[note 1]
Microscopic discovery of microorganisms (animalcule)
Scientific career
Fields Microscopy
Microbiology
Influences Robert Hooke
Regnier de Graaf
Influenced History of biology and life sciences
Natural history
Scientific Revolution
Age of Reason
Signature
Antonie van Leeuwenhoek Signature.svg

Antonie Philips van Leeuwenhoek[note 2] (/ˈleɪvənhʊk/; Dutch: [ɑnˈtoːni vɑn ˈleːuə(n)ˌɦuk] (About this sound listen); 24 October 1632 – 26 August 1723) was a Dutch businessman and scientist in the Golden Age of Dutch science and technology. A largely self-taught man in science, he is commonly known as "the Father of Microbiology", and one of the first microscopists and microbiologists.[5][6] Van Leeuwenhoek is best known for his pioneering work in microscopy and for his contributions toward the establishment of microbiology as a scientific discipline.

Raised in Delft, in the Dutch Republic, van Leeuwenhoek worked as a draper in his youth and founded his own shop in 1654. He became well recognized in municipal politics and developed an interest in lensmaking. In the 1670s, he started to explore microbial life with his microscope.[note 3] This was one of the notable achievements of the Golden Age of Dutch exploration and discovery (c. 1590s–1720s).

Using single-lensed microscopes of his own design, van Leeuwenhoek was the first to experiment with microbes, which he originally referred to as animalcules (from Latin animalculum = "tiny animal"). Through his experiments, he was the first to relatively determine their size. Most of the "animalcules" are now referred to as unicellular organisms, although he observed multicellular organisms in pond water. He was also the first to document microscopic observations of muscle fibers, bacteria, spermatozoa, red blood cells, crystals in gouty tophi, and blood flow in capillaries. Van Leeuwenhoek did not write any books; his discoveries came to light through correspondence with the Royal Society, which published his letters.

Early life and career

van Leeuwenhoek's birth house in Delft, in the Netherlands, in 1926 before it was demolished

Antonie van Leeuwenhoek was born in Delft, Dutch Republic, on 24 October 1632. On 4 November, he was baptized as Thonis. His father, Philips Antonisz van Leeuwenhoek, was a basket maker who died when Antonie was only five years old. His mother, Margaretha (Bel van den Berch), came from a well-to-do brewer's family. She remarried Jacob Jansz Molijn, a painter. Antonie had four older sisters, Margriet, Geertruyt, Neeltje, and Catharina.[7] When he was around ten years old his step-father died. He attended school in Warmond for a short time before being sent to live in Benthuizen with his uncle, an attorney. At the age of 16 he became a bookkeeper's apprentice at a linen-draper's shop in Amsterdam,[8] which was owned by the Scot William Davidson. Van Leeuwenhoek left there after six years.[9][10]

Van Leeuwenhoek married Barbara de Mey in July 1654, with whom he fathered one surviving daughter, Maria (four other children died in infancy). That same year he returned to Delft, where he would live and study for the rest of his life. He opened a draper's shop, which he ran throughout the 1650s. His wife died in 1666, and in 1671, Van Leeuwenhoek remarried to Cornelia Swalmius with whom he had no children.[11] His status in Delft had grown throughout the years. In 1660 he received a lucrative job as chamberlain for the assembly chamber of the Delft sheriffs in the city hall, a position which he would hold for almost 40 years. In 1669 he was appointed as a land surveyor by the court of Holland; at some time he combined it with another municipal job, being the official "wine-gauger" of Delft and in charge of the city wine imports and taxation.[12]

Painting of man with scroll and compass, standing by sunlit window
The Geographer by Johannes Vermeer

Van Leeuwenhoek was a contemporary of another famous Delft citizen, the painter Johannes Vermeer, who was baptized just four days earlier. It has been suggested that he is the man portrayed in two Vermeer paintings of the late 1660s, The Astronomer and The Geographer, but others argue that there appears to be little physical similarity. Because they were both relatively important men in a city with only 24,000 inhabitants, it is likely that they were at least acquaintances; Van Leeuwenhoek acted as the executor of Vermeer's will after the painter died in 1675.[13][note 4]

Microscopic study

See also: Microscopic discovery of microorganisms

While running his draper shop, van Leeuwenhoek wanted to see the quality of the thread better than possible using magnifying lenses then available. He began to develop an interest in lensmaking, although few records exist of his early activity. Van Leeuwenhoek's interest in microscopes and a familiarity with glass processing led to one of the most significant, and simultaneously well-hidden, technical insights in the history of science.[citation needed]

By placing the middle of a small rod of soda lime glass in a hot flame, van Leeuwenhoek could pull the hot section apart to create two long whiskers of glass. Then, by reinserting the end of one whisker into the flame, he could create a very small, high-quality glass sphere. These spheres became the lenses of his microscopes, with the smallest spheres providing the highest magnifications.[14]

See caption
A microscopic section of a one-year-old ash tree (Fraxinus) wood, drawing made by van Leeuwenhoek

Recognition by the Royal Society

After developing his method for creating powerful lenses and applying them to the study of the microscopic world, van Leeuwenhoek introduced his work to his friend, the prominent Dutch physician Reinier de Graaf. When the Royal Society in London published the groundbreaking work of an Italian lensmaker in their journal Philosophical Transactions of the Royal Society, de Graaf wrote to the editor of the journal, Henry Oldenburg, with a ringing endorsement of van Leeuwenhoek's microscopes which, he claimed, "far surpass those which we have hitherto seen". In response, in 1673 the society published a letter from van Leeuwenhoek that included his microscopic observations on mold, bees, and lice.[15]

Page in a handwritten manuscript volume
A 1677 letter from van Leeuwenhoek to Oldenburg, with the latter's English translation behind, the full correspondence remains in the Royal Society Library

Van Leeuwenhoek's work fully captured the attention of the Royal Society, and he began corresponding regularly with the society regarding his observations. At first he had been reluctant to publicize his findings, regarding himself as a businessman with little scientific, artistic, or writing background, but de Graaf urged him to be more confident in his work.[16] By the time van Leeuwenhoek died in 1723, he had written some 190 letters to the Royal Society, detailing his findings in a wide variety of fields, centered on his work in microscopy. He only wrote letters in his own colloquial Dutch; he never published a proper scientific paper in Latin. He strongly preferred to work alone, distrusting the sincerity of those who offered their assistance.[17] The letters were translated into Latin or English by Henry Oldenburg, who had learned Dutch for this very purpose. Despite the initial success of van Leeuwenhoek's relationship with the Royal Society, soon relations became severely strained. In 1676, his credibility was questioned when he sent the Royal Society a copy of his first observations of microscopic single-celled organisms. Previously, the existence of single-celled organisms was entirely unknown. Thus, even with his established reputation with the Royal Society as a reliable observer, his observations of microscopic life were initially met with some skepticism.[18]

Eventually, in the face of van Leeuwenhoek's insistence, the Royal Society arranged for Alexander Petrie, minister to the English Reformed Church in Delft; Benedict Haan, at that time Lutheran minister at Delft; and Henrik Cordes, then Lutheran minister at the Hague, accompanied by Sir Robert Gordon and four others, to determine whether it was in fact van Leeuwenhoek's ability to observe and reason clearly, or perhaps, the Royal Society's theories of life that might require reform. Finally in 1677,[19] van Leeuwenhoek's observations were fully acknowledged by the Royal Society.[20]

Antonie van Leeuwenhoek was elected to the Royal Society in February 1680 on the nomination of William Croone, a then-prominent physician.[note 5] Van Leeuwenhoek was "taken aback" by the nomination, which he considered a high honor, although he did not attend the induction ceremony in London, nor did he ever attend a Royal Society meeting.[22]

Scientific fame

By the end of the seventeenth century, van Leeuwenhoek had a virtual monopoly on microscopic study and discovery. His contemporary Robert Hooke, an early microscope pioneer, bemoaned that the field had come to rest entirely on one man's shoulders.[23] He was visited over the years by many notable individuals, such as the Russian Tsar Peter the Great. To the disappointment of his guests, van Leeuwenhoek refused to reveal the cutting-edge microscopes he relied on for his discoveries, instead showing visitors a collection of average-quality lenses.[24]

An experienced businessman, van Leeuwenhoek believed that if his simple method for creating the critically important lens was revealed, the scientific community of his time would likely disregard or even forget his role in microscopy. He therefore allowed others to believe that he was laboriously spending most of his nights and free time grinding increasingly tiny lenses to use in microscopes, even though this belief conflicted both with his construction of hundreds of microscopes and his habit of building a new microscope whenever he chanced upon an interesting specimen that he wanted to preserve. He made about 200 microscopes with a different magnification.[citation needed]

Van Leeuwenhoek was visited by Leibniz, William III of Orange and his wife, Mary II of England, and the burgemeester (mayor) Johan Huydecoper of Amsterdam, the latter being very interested in collecting and growing plants for the Hortus Botanicus Amsterdam, and all gazed at the tiny creatures. In 1698, van Leeuwenhoek was invited to visit the Tsar Peter the Great on his boat. On this occasion van Leeuwenhoek presented the Tsar an "eel-viewer", so Peter could study blood circulation whenever he wanted.[citation needed]

Techniques and discoveries

Schematic drawings
van Leeuwenhoek's microscopes by Henry Baker

Antonie van Leeuwenhoek made more than 500 optical lenses. He also created at least 25 single-lens microscopes, of differing types, of which only nine have survived. These microscopes were made of silver or copper frames, holding hand-made lenses. Those that have survived are capable of magnification up to 275 times. It is suspected that van Leeuwenhoek possessed some microscopes that could magnify up to 500 times. Although he has been widely regarded as a dilettante or amateur, his scientific research was of remarkably high quality.[25]

The single-lens microscopes of van Leeuwenhoek were relatively small devices, the largest being about 5 cm long.[26][27] They are used by placing the lens very close in front of the eye, while looking in the direction of the sun. The other side of the microscope had a pin, where the sample was attached in order to stay close to the lens. There were also three screws to move the pin and the sample along three axes: one axis to change the focus, and the two other axes to navigate through the sample.

Van Leeuwenhoek maintained throughout his life that there are aspects of microscope construction "which I only keep for myself", in particular his most critical secret of how he made the lenses. For many years no-one was able to reconstruct van Leeuwenhoek's design techniques, however, in 1957, C.L. Stong used thin glass thread fusing instead of polishing, and successfully created some working samples of a van Leeuwenhoek design microscope.[28] Such a method was also discovered independently by A. Mosolov and A. Belkin at the Russian Novosibirsk State Medical Institute.[29]

See caption
A replica of a microscope by van Leeuwenhoek

Van Leeuwenhoek used samples and measurements to estimate numbers of microorganisms in units of water.[30][31] He also made good use of the huge advantage provided by his method. He studied a broad range of microscopic phenomena, and shared the resulting observations freely with groups such as the British Royal Society.[32] Such work firmly established his place in history as one of the first and most important explorers of the microscopic world. Antonie van Leeuwenhoek was one of the first people to observe cells, much like Robert Hooke.[33]

Van Leeuwenhoek's main discoveries are:

In 1687, van Leeuwenhoek reported his research on the coffee bean. He roasted the bean, cut it into slices and saw a spongeous interior. The bean was pressed, and an oil appeared. He boiled the coffee with rain water twice and set it aside.[36]

Like Robert Boyle and Nicolaas Hartsoeker, van Leeuwenhoek was interested in dried cochineal, trying to find out if the dye came from a berry or an insect.[37][38][39]

Antonie van Leeuwenhoek's religion was "Dutch Reformed" Calvinist.[40] He often referred with reverence to the wonders God designed in making creatures great and small. He believed that his amazing discoveries were merely further proof of the great wonder of God's creation.[41][42]

Legacy and recognition

Gravestone with Dutch inscription
Antonie van Leeuwenhoek is buried in the Oude Kerk in Delft.
A cluster of Escherichia coli bacteria magnified 10,000 times. In the early modern period, Leeuwenhoek's discovery and study of the microscopic world, like the Dutch discovery and mapping of largely unknown lands and skies, is considered one of the most notable achievements of the Golden Age of Dutch exploration and discovery (c. 1590s–1720s).

By the end of his life, van Leeuwenhoek had written approximately 560 letters to the Royal Society and other scientific institutions concerning his observations and discoveries. Even during the last weeks of his life, van Leeuwenhoek continued to send letters full of observations to London. The last few contained a precise description of his own illness. He suffered from a rare disease, an uncontrolled movement of the midriff, which now is named van Leeuwenhoek's disease.[43] He died at the age of 90, on 26 August 1723, and was buried four days later in the Oude Kerk in Delft.[citation needed]

In 1981, the British microscopist Brian J. Ford found that van Leeuwenhoek's original specimens had survived in the collections of the Royal Society of London. They were found to be of high quality, and all were well preserved.[44][45][46] Ford carried out observations with a range of single-lens microscopes, adding to our knowledge of van Leeuwenhoek's work.[47]

Ford, as a Leeuwenhoek expert, wrote of him (1992):

“Antony van Leeuwenhoek remains one of the most imperfectly understood figures in the origins of experimental biology. The popular view is that Leeuwenhoek worked in a manner that was essentially crude and undisciplined, using untried methods of investigation that were lacking in refinement and objectivity. He has often been designated as a 'dilettante.' His microscopes, furthermore, have been described as primitive and doubt has been expressed over his ability to have made many of the observations attributed to him. Recent research shows these views to be erroneous.
"His work was carried out conscientiously, and the observations were recorded with painstaking diligence. Though we may see evidence of his globulist understanding of organic matter (and indeed, this view has frequently been cited as evidence of his observational inadequacies), this minor preoccupation cannot detract from two firm principles that underlie his work: (a) a clear ability to construct experimental procedures which were, for their time, rational and repeatable, and (b) a willingness both to fly in the face of received opinion – for example, over the question of spontaneous generation – and to abandon a previously held belief in the light of new evidence.
"In his method of analysing a problem, Leeuwenhoek was able to lay many of the ground rules of experimentation and did much to found, not only the science of microscopy, but also the philosophy of biological experimentation.” [25]

With regard to Leeuwenhoek's importance in history of microbiology and science in general, British biochemist Nick Lane has written (2015):

“More than being the first to see this unimagined world of 'animalcules', he was the first even to think of looking—certainly, the first with the power to see. Using his own deceptively simple, single-lensed microscopes, he did not merely observe, but conducted ingenious experiments, exploring and manipulating his microscopic universe with a curiosity that belied his lack of a map or bearings. Leeuwenhoek was a pioneer, a scientist of the highest calibre, yet his reputation suffered at the hands of those who envied his fame or scorned his unschooled origins, as well as through his own mistrustful secrecy of his methods, which opened a world that others could not comprehend.” [18]

The Antoni van Leeuwenhoek Hospital in Amsterdam, named after van Leeuwenhoek, is specialized in oncology.[48]

In 2004, a public poll in the Netherlands to determine the greatest Dutchman ("De Grootste Nederlander") named van Leeuwenhoek the 4th-greatest Dutchman of all time.

On 24 October 2016, Google commemorated the 384th anniversary of van Leeuwenhoek's birth with a Doodle that depicted his discovery of "little animals" or animalcules, now known as bacteria.[49]

Leeuwenhoek Medal, Leeuwenhoek Lecture, Leeuwenhoek (crater), Leeuwenhoeckia, Levenhookia (a genus of species in the family Stylidiaceae), and Leeuwenhoekiella (an aerobic bacterial genus) are named after him.

Notable quotes

See also

Notes

  1. Jump up ^ Van Leeuwenhoek is universally acknowledged as the father of microbiology because he was the first to undisputedly discover/observe, describe, study, conduct scientific experiments with microscopic organisms (microbes), and relatively determine their size, using single-lensed microscopes of his own design.[1] Leeuwenhoek is also considered to be the father of bacteriology and protozoology (recently known as protistology).[2][3]
  2. Jump up ^ The spelling of van Leeuwenhoek's name is exceptionally varied. He was christened as Thonis, but always went by Antonj (corresponding with the English Antony). The final j of his given name is the Dutch tense i. Until 1683 he consistently used the spelling Antonj Leeuwenhoeck (ending in –oeck) when signing his letters. Throughout the mid-1680s he experimented with the spelling of his surname, and after 1685 settled on the most recognized spelling, van Leeuwenhoek.[4]
  3. Jump up ^ Note that the existence of microscopic organisms (microbes, microorganisms) was predicted or hypothesized many centuries before they were first observed by van Leeuwenhoek.
  4. Jump up ^ In A Short History of Nearly Everything (p. 236) Bill Bryson alludes to rumors that Vermeer's mastery of light and perspective came from use of a camera obscura produced by Van Leeuwenhoek. This is one of the examples of the controversial Hockney–Falco thesis, which claims that some of the Old Masters used optical aids to produce their masterpieces.
  5. Jump up ^ He was also nominated as a "corresponding member" of the French Academy of Sciences in 1699, but there is no evidence that the nomination was accepted, nor that he was ever aware of it.[21]
  6. Jump up ^ The "Lens on Leeuwenhoek" site, which is exhaustively researched and annotated, prints this letter in the original Dutch and in English translation, with the date 17 September 1683. Assuming that the date of 1676 is accurately reported from Pommerville (2014), that book seems more likely to be in error than the intensely detailed, scholarly researched website focused entirely on van Leeuwenhoek.
  7. Jump up ^ Sixty-two years later, in 1745, a physician correctly attributed a diarrhea epidemic to van Leeuwenhoek's "bloodless animals" (Valk 1745, cited by Moll 2003).

References

  1. Jump up ^ Lane, Nick (6 March 2015). "The Unseen World: Reflections on Leeuwenhoek (1677) 'Concerning Little Animal'." Philos Trans R Soc Lond B Biol Sci. 2015 Apr; 370 (1666): 20140344. [doi:10.1098/rstb.2014.0344]
  2. Jump up ^ Dobell, Clifford (1923). "A Protozoological Bicentenary: Antony van Leeuwenhoek (1632–1723) and Louis Joblot (1645–1723)". Parasitology. 15: 308–19. doi:10.1017/s0031182000014797. 
  3. Jump up ^ Corliss, John O (1975). "Three Centuries of Protozoology: A Brief Tribute to its Founding Father, A. van Leeuwenhoek of Delft". The Journal of Protozoology. 22 (1): 3–7. doi:10.1111/j.1550-7408.1975.tb00934.x. 
  4. Jump up ^ Dobell, pp. 300–305.
  5. Jump up ^ Chung, King-thom; Liu, Jong-kang: Pioneers in Microbiology: The Human Side of Science. (World Scientific Publishing, 2017, ISBN 978-9813202948). "We may fairly call Leeuwenhoek “The first microbiologist” because he was the first individual to actually culture, see, and describe a large array of microbial life. He actually measured the multiplication of the bugs. What is more amazing is that he published his discoveries."
  6. Jump up ^ "Life at the Edge of Sight — Scott Chimileski, Roberto Kolter | Harvard University Press". www.hup.harvard.edu. Retrieved 2018-01-26. 
  7. Jump up ^ Dobell, pp. 19–21.
  8. Jump up ^ Dobell, pp. 23–24.
  9. Jump up ^ The curious observer. Events of the first half of van Leeuwenhoek's life. Lens on Leeuwenhoek (1 September 2009). Retrieved 20 April 2013.
  10. Jump up ^ Huerta, p. 31.
  11. Jump up ^ Dobell, pp. 27–31.
  12. Jump up ^ Dobell, pp. 33–37.
  13. Jump up ^ Van Berkel, K. (24 February 1996). Vermeer, Van Leeuwenhoek en De Astronoom. Vrij Nederland (Dutch magazine), p. 62–67.
  14. Jump up ^ "Anton van Leeuwenhoek – History of the compound microscope". www.history-of-the-microscope.org. Retrieved 2017-09-29. 
  15. Jump up ^ Dobell, pp. 37–41.
  16. Jump up ^ Dobell, pp. 41–42.
  17. Jump up ^ Dobell, pp. 43–44.
  18. ^ Jump up to: a b Lane, Nick (6 Mar 2015). "The Unseen World: Reflections on Leeuwenhoek (1677) 'Concerning Little Animal'". Philos Trans R Soc Lond B Biol Sci 2015 Apr 19; 370(1666). Retrieved 16 Jan 2017. 
  19. Jump up ^ Schierbeek, A.: "The Disbelief of the Royal Society." Measuring the Invisible World. London and New York: Abelard-Schuman, 1959. N. pag. Print.
  20. Jump up ^ Full text of "Antony van Leeuwenhoek and his "Little animals"; being some account of the father of protozoology and bacteriology and his multifarious discoveries in these disciplines;". Recall.archive.org. Retrieved 20 April 2013.
  21. Jump up ^ Dobell, pp. 53–54.
  22. Jump up ^ Dobell, pp. 46–50.
  23. Jump up ^ Dobell, pp. 52–53.
  24. Jump up ^ Dobell, pp. 54–61.
  25. ^ Jump up to: a b Brian J. Ford (1992). "From Dilettante to Diligent Experimenter: a Reappraisal of Leeuwenhoek as microscopist and investigator". Biology History. 5 (3). 
  26. Jump up ^ Anderson, Douglas. "Tiny Microscopes". Lens on Leeuwenhoek. Archived from the original on 2 May 2015. Retrieved 3 March 2016. 
  27. Jump up ^ Lens on Leeuwenhoek: How he made his tiny microscopes. Lensonleeuwenhoek.net. Retrieved 15 September 2013.
  28. Jump up ^ "A glass-sphere microscope". Funsci.com. Archived from the original on 11 June 2010. Retrieved 13 June 2010. 
  29. Jump up ^ A. Mosolov & A. Belkin (1980). "Secret of Antony van Leeuwenhoek?". Nauka i Zhizn (Science and Life). 09-1980: 80–82. 
  30. Jump up ^ F. N. Egerton (1967). "Leeuwenhoek as a founder of animal demography". Journal of the History of Biology. 1: 1–22. doi:10.1007/BF00149773. JSTOR 4330484. 
  31. Jump up ^ Frank N. Egerton (2006). "A History of the Ecological Sciences, Part 19: Leeuwenhoek's Microscopic Natural History". Bulletin of the Ecological Society of America. 87: 47. doi:10.1890/0012-9623(2006)87[47:AHOTES]2.0.CO;2. 
  32. Jump up ^ "Robert Hooke (1635–1703)". Ucmp.berkeley.edu. Retrieved 13 June 2010. 
  33. Jump up ^ "Life at the Edge of Sight — Scott Chimileski, Roberto Kolter | Harvard University Press". www.hup.harvard.edu. Retrieved 2018-01-26. 
  34. Jump up ^ Anderson, Douglas. "Wrote Letter 39 of 1683-09-17 (AB 76) to Francis Aston". Lens on Leeuwenhoek. Archived from the original on 20 August 2016. Retrieved 26 September 2016. 
  35. Jump up ^ Pommerville, Jeffrey (2014). Fundamentals of microbiology. Burlington, MA: Jones & Bartlett Learning. p. 6. ISBN 978-1-4496-8861-5. 
  36. Jump up ^ 9 May 1687, Missive 54.
  37. Jump up ^ Antoni van Leeuwenhoek; Samuel Hoole (1800). The Select Works of Antony van Leeuwenhoek, Containing His Microscopical Discoveries in Many of the Works of Nature. G. Sidney. pp. 213–. 
  38. Jump up ^ Rocky Road: Leeuwenhoek. Strangescience.net (22 November 2012). Retrieved 20 April 2013.
  39. Jump up ^ Greenfield, Amy Butler (2005). A Perfect Red: Empire, Espionage, and the Quest for the Color of Desire. New York: Harper Collins Press. ISBN 0-06-052276-3
  40. Jump up ^ "The religious affiliation of Biologist A. van Leeuwenhoek". Adherents.com. 8 July 2005. Archived from the original on 7 July 2010. Retrieved 13 June 2010. 
  41. Jump up ^ "The Religion of Antony van Leeuwenhoek". 2006. Archived from the original on 4 May 2006. Retrieved 23 April 2006. 
  42. Jump up ^ A. Schierbeek, Editor-in-Chief of the Collected Letters of A. van Leeuwenhoek, Measuring the Invisible World: The Life and Works of Antoni van Leeuwenhoek F R S, Abelard-Schuman (London and New York, 1959), QH 31 L55 S3, LC 59-13233. This book contains excerpts of van Leeuwenhoek's letters and focuses on his priority in several new branches of science, but makes several important references to his spiritual life and motivation.
  43. Jump up ^ Life and work of Antoni van Leeuwenhoek of Delft in Holland; 1632–1723 (1980) Published by the Municipal Archives Delft, p. 9
  44. Jump up ^ Biology History vol 5(3), December 1992
  45. Jump up ^ The Microscope vol 43(2) pp 47–57
  46. Jump up ^ Spektrum der Wissenschaft pp 68–71, June 1998
  47. Jump up ^ "The discovery by Brian J Ford of Leeuwenhoek's original specimens, from the dawn of microscopy in the 16th century". Brianjford.com. Retrieved 13 June 2010. 
  48. Jump up ^ Antoni van Leeuwenhoek (in Dutch). Retrieved 25 October 2016.
  49. Jump up ^ New Google Doodle Celebrates Antoni van Leeuwenhoek, Inventor of Microbiology, Retrieved 24 October 2016.
  50. Jump up ^ Kelly, Kate: The Scientific Revolution and Medicine: 1450–1700. (Facts on File, 2009, ISBN 978-0816072071, p. 81)

Sources

External links

at

No comments:

Post a Comment

Subscribe to: Post Comments (Atom)

Wikipedia

<!-- CentralNotice Main Page From Wikipedia, the free encyclopedia Jump to: navigation , search ...