Skip to main content
SpringerLink
Log in

Images and ideas: Leeuwenhoek's perception of the spermatozoa

  • Published:
Journal of the History of Biology Aims and scope Submit manuscript

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

References

  1. Henry Power, Experimental Philosophy, in Three Books (London: printed by T. Roycroft for John Martin and James Allestry, 1664), p. [xviii] in “The Preface to the Ingenious Reader.”

  2. Henry Power, Experimental Philosophy, in Three Books (London: printed by T. Roycroft for John Martin and James Allestry, 1664), p. [xviii] in “The Preface to the Ingenious Reader.” [vii–viii].

  3. See Gottfried Wilhelm Leibniz, Die philosophischen Schriften, ed. C. I. Gerhardt (Hildesheim: Georg Olms, 1960–1961), IV, 474, 480.

    Google Scholar 

  4. Antoni van Leeuwenhoek to Henry Oldenburg, 7 September 1674, in Leeuwenhoek, Alle de Brieven (Amsterdam: Swets & Zeitlinger, 1939-), I, 166–167. Cited hereafter as Leeuwenhoek, A.d.B.

  5. Regnier de Graaf to Henry Oldenburg, 18 April 1673, in Oldenburg, Correspondence, ed. and trans. A. Rupert Hall and Marie Boas Hall (Madison: University of Wisconsin Press, 1965-), IX, 602–603.

  6. Leeuwenhoek to Antonie Heinsius, 17 December 1712, in Leeuwenhoek, Send-Brieven (Delft: Adriaan Beman, 1718), p. 22; Leeuwenhoek to the Royal Society, 10 July 1686, A.d.B., VI, 128–129; Leeuwenhoek to Hendrik van Bleyswyk, 28 December 1695, in Leeuwenhoek, Sesde Vervolg der Brieven (Delft: Henrik van Krooneveld, 1697), p. 186; Leeuwenhoek to the Royal Society, 15 June 1717, Send-Brieven, p. 372; Leeuwenhoek to the Royal Society, 20 November 1717, ibid., p. 453.

  7. Leeuwenhoek to Henry Oldenburg, 4 December 1674, in Leeuwenhoek, A.d.B., I, 202–203; Leeuwenhoek to Constantijn Huygens, 26 December 1674, ibid., pp. 206–207; Leeuwenhoek to Henry Oldenburg, 9 October 1676, ibid., II, 142–143; Leeuwenhoek to Lambert van Velthuysen, 14 November 1679, ibid., III, 136–139.

  8. Constantijn Huygens to Robert Hooke, 8 August 1673, in Huygens, Briefwisseling, ed. J. A. Worp (The Hague: Martinus Nijhoff, 1911–1917), VI, 330–331.

  9. Leeuwenhoek to Henry Oldenburg, 15 August 1673, in Leeuwenhoek, A.d.B., I, 42–43.

  10. Leeuwenhoek to Henry Oldenburg, 30 October 1676, ibid., II, 164–165; Leeuwenhoek to Nehemiah Grew, 31 May 1678, ibid., pp. 356–357; Leeuwenhoek to Robert Hooke, 3 March 1682, ibid., III, 384–385; Leeuwenhoek to the Royal Society, 12 August 1692, in Leeuwenhoek, Derde Vervolg der Brieven (Delft: Henrik van Kroonevelt, 1693), p. 507; Leeuwenhoek to a “Hoog Geleerde Heer,” 16 June 1700, in Leeuwenhoek, Sevende Vervolg der Brieven (Delft: Henrik van Krooneveld, 1702), p. 274; Leeuwenhoek to the Royal Society, 4 November 1704, Leeuwenhoek Letters, Royal Society Library, London, EL.L3.69, fol. 320r.

  11. Leeuwenhoek to Henry Oldenburg, 4 December 1674, in Leeuwenhoek, A.d.B., I, 202–203.

  12. Leeuwenhoek to Henry Oldenburg, 22 January 1675, ibid., pp. 210–211; Leeuwenhoek to Henry Oldenburg, 26 March 1675, ibid., pp. 278–279; Leeuwenhoek to Henry Oldenburg, 20 December 1675, ibid., pp. 330–331; Leeuwenhoek to Nehemiah Grew, 25 April 1679, ibid., III, 22–23.

  13. Leeuwenhoek to Nehemiah Grew, 18 March 1678, ibid., II, 328–339, esp. 332–339.

  14. Leeuwenhoek to the Royal Society, 30 March 1685, ibid., V, 150–153.

  15. Ibid., pp. 172–173.

  16. Leeuwenhoek to William Brouncker, November 1677, ibid., II, 290–291.

  17. Ibid., pp. 280–283; Leeuwenhoek to Lambert van Velthuysen, 13 June 1679, ibid., III, 74–75; Leeuwenhoek to Herman van Zoelen, 17 December 1698, in Leeuwenhoek, Sevende Vervolg, p. 65. The donor of the specimen was a patient afflicted with gonorrhea, and since the discharge symptomatic of the disease was often identified with semen, it is not unlikely that the specimen was in fact this gonococcal discharge. (Regarding the instruction at Leiden in particular, see Ham's own relative Theodorus Craanen, Tractatus physico-medicus de homine [Leiden: Petrus vander Aa, 1689], p. 750, and Gysbertus van Tol, Disputatio medica inauguralis, de gonorrhoea virulenta [Leiden: Vidua & Haeredes Johannis Elsevirii, 1674], Caput I, S. 5; see also Regnier de Graaf, Tractatus de virorum organis generationi inservientibus, in Opera omnia [Leiden: Officina Hackiana, 1677], pp. 88–89.) I am grateful to Dr. F. Marc Laforce of the University of Colorado School of Medicine for reassurance that it is not unusual to find spermatozoa in such discharge. It is possible that Ham himself had already made other observations of spermatozoa in healthy specimens of semen, for Fridericus Schrader of Helmstad, who had enrolled in the medical school at Leiden shortly after Ham's visit (his second, in fact) to Leeuwenhoek and graduated two years later, wrote in 1681 that his “very dear friend” Ham had first discovered spermatozoa in the Netherlands in the semen of a rooster. (Album studiosorum Academiae Lugduno Batavae MDLXXV-MDCCCLXXV [The Hague: Martinus Nijhoff, 1875], col. 616; “Catalogus promotorum,” in P. C. Molhuysen, ed., Bronnen tot de Geschiedenis der Leidsche Universiteit [The Hague: Martinus Nijhoff, 1913–1924], III, 331.) Ham had also told him, Schrader added, that he had found all the spermatozoa dead in the semen of those suffering from “virulent” gonorrhea. (Fridericus Schrader, Dissertatio epistolica de microscopiorum usu in naturali scientia & anatome [Göttingen: Sumptibus Bartholdi Fuhrmanns, typis Johannis Christophori Hampii, 1681], pp. 34–35.) On 12 January 1679 in Bologna, moreover, Marcello Malpighi noted the report of a “German friend” (Schrader?) that “animals like extremely small toads, dead and deprived of motion”, could be observed in the semen of those with gonorrhea. (Howard B. Adelmann, Marcello Malpighi and the Evolution of Embryology [Ithaca, N.Y.: Cornell University Press, 1966], I, 420.) According to Leeuwenhoek, however, both he and Ham had observed living spermatozoa in the specimen that the latter had brought, and Ham had judged that they lived perhaps twenty-four hours; Ham also reported having observed them dead after the patient had taken turpentine (Leeuwenhoek to William Brouncker, November 1677, in Leeuwenhoek, A.d.B., II, 282–283.) See also note 24.

  18. Leeuwenhoek to William Brouncker, November 1677, in Leeuwenhoek, A.d.B., II, 284–291.

  19. Pieter Rabus, friend and admirer of Leeuwenhoek as well as publisher of the Dutch-language periodical De Boekzaal van Europe, restrained his discussion of some of Leeuwenhoek's later observations because he knew the Boekzaal was also seen by “delicate eyes” (De Boekzaal van Europe, VII [July-December 1695], 473) and suggested to Leeuwenhoek that he translate certain of his ideas on the impregnation of the female into Latin to make them known to the world. (Leeuwenhoek to Pieter Rabus, 30 November 1694, in Leeuwenheok, Vijfde Vervolg der Brieven [Delft: Henrik van Krooneveld, 1696], pp. 12–13.) In the bilingual catalogue of Leeuwenhoek's microscopes auctioned at Delft in 1747, preparations of spermatozoa and of the genitalia of fleas and lice were also specified in the Latin but not in the more modest Dutch text. (Catalogus van het vermaarde Cabinet van Vergrootglasen, met zeer veel Moeite, en Kosten in veele Jaren geïnventeert, gemaakt, en nagelaten door wylen den Heer Anthony van Leeuwenhoek [Delft: Reinier Boitet, 1747], items 24, 28, 33, 35, pp. 10–11, 12–13, 14–15.)

  20. Leeuwenhoek to William Brouncker, November 1677, in Leeuwenhoek, A.d.B., II, 290–293. He was apparently reassured, for Leeuwenhoek's subsequent letters would deal unabashedly with his investigations of sex-related matters, and in 1679 he showed the spermatozoa of a dog to no one less than the visiting Duke of York. (Leeuwenhoek to Robert Hooke, 13 October 1679, ibid., III, 106–109.) But he would continue on occasion to censor his speculations, for he feared not only their impropriety but “that the world, which is coarse and vicious enough, might use the knowledge of nature for its own ruin and increasingly debauch itself in depravity.” (Leeuwenhoek to Pieter Rabus, 30 November 1694, in Leeuwenhoek, Vijfde Vervolg, p. 13.)

  21. Text of letter from Constantijn Huygens to Leeuwenhoek, 8 December 1677, given in Leeuwenhoek to Herman van Zoelen, 17 December 1698, in Leeuwenhoek, Sevende Vervolg, pp. 68–69.

  22. Ibid.; Christiaan Huygens, Dioptrica, in Oeuvres complètes, published by the Société Hollandaise des Sciences (The Hague: Martinus Nijhoff, 1888–1950), XIII, 524–527. For other examples of the spermatozoa being exalted above all of Leeuwenhoek's other observations, see Martin Folkes, “Some Account of Mr. Leeuwenhoek's Curious Microscopes, Lately Presented to the Royal Society,” Phil. Trans., 380 (November–December 1723), 449; Rudolphus Forsten, Oratio de belgarum meritis in oeconomia corporis humani extricanda (Harderwijk: Joannes Mooien, 1776), pp. 47–48.

  23. Martin Folkes, “Some Account of Mr. Leeuwenhoek's Curious Microscopes,” p. 449; Pieter Boddaert, Natuurkundige Beschouwing der Dieren (Utrecht: J. van Driel, [1778]), p. xxiii.

  24. Christiaan expressed his sense of the importance of the spermatozoa and their relevance to the generation of animals in announcing their discovery the following year in Paris. (Christiaan Huygens, “Extrait d'une Lettre de M. Huguens de l'Acad. R. des Sciences à l'Auteur du Journal, touchant une nouvelle maniere de Microscope qu'il a apporté de Hollande,” J. Sçavans, 15 August 1678, vol. 6, Amsterdam ed. [1679], 347.) Fridericus Schrader (see note 17) related that Ham, having first discovered the spermatozoa in the semen of a rooster, told him that he had also investigated the semen of sterile men, finding in it no spermatozoa at all, as well as the semen of those suffering from virulent gonorrhea: (Fridericus Schrader, De microscopiorum usu, pp. 34–35.) If this is so, such a line of inquiry certainly suggests an interest in a possible connection between the spermatozoa and generation, although the date of these investigations is not disclosed.

  25. Carlo Castellani, “Spermatozoan Biology from Leeuwenhoek to Spallanzani,” J. Hist. Biol., 6 (1973), 40; Leeuwenhoek, A.d.B., II, 294n33, 295n31.

    Google Scholar 

  26. Leeuwenhoek to William Brouncker, November 1677, in Leeuwenhoek, A.d.B., II, 292–295.

  27. Leeuwenhoek to Nehemiah Grew, 18 March 1678, ibid., pp. 336–339.

  28. Leeuwenhoek to Nehemiah Grew, 31 May 1678, ibid., pp. 364–367, and “Tables” 18 and 19.

  29. Leeuwenhoek to William Brouncker, November 1677, ibid., pp. 292–297; Leeuwenhoek to Nehemiah Grew, 18 March 1678, ibid., pp. 336–337. The English translation given in A.d.B., II, for Leeuwenhoek's letter of 31 May 1678 to Nehemiah Grew introduces a very misleading idea. Leeuwenhoek's reference on p. 362 to spermatozoa among the ostensible vessels of the semen acquires in translation (p. 363) the sense that the spermatozoa came to be among the vessels “by their escaping from the vessels” when the latter were broken, suggesting that the spermatozoa had been contained within the vessels (see 362n29 and 363n9 in this volume of the A.d.B.). I find nothing in the original Dutch passage to justify the introduction of the cited phrase or the attendant implication. Leeuwenhoek initially wrote that he had observed the spermatozoa primarily in the thinner, fluid part of the semen around the thicker part, which, composed of vessels, was in fact too densely packed, he surmised, to allow the spermatozoa to move in it. (Leeuwenhoek to William Brouncker, November 1677, ibid., pp. 284–287, 292–293.) In his letter to Grew, Leeuwenhoek is attempting to explain how some spermatozoa were also found among the vessels. The answer he offers is that when the vessels were broken apart in the semen spilled as the male animal mounted the female, the spermatozoa were able to swim in among them. Since he had earlier observed (or so he reported) that these vessels, when exposed to the air for a few moments, turned into a watery substance and oily globules like those he had seen among the putative vessels of the spinal marrow as well, he conjectured that the vessels of the semen might in fact carry animal spirits (ibid., pp. 294–297), presumably because the nerves and supposed vessels of the spinal cord were widely believed to carry these spirits. Leeuwenhoek indicated that the “body” — that is, the head — of the spermatozoa he had drawn for the Royal Society was perhaps slightly thicker than the prominent vessels of the semen he had drawn, the smaller of which, however, were so small as to escape his isght. (Leeuwenhoek to Nehemiah Grew, 31 May 1678, ibid., pp. 364–367.) True to the near-equivalence of diameters thus suggested, he described the diameter of these prominent vessels as less than a hundredth the diameter of a large grain of sand (ibid.) and also judged that such a grain of sand would be larger in volume than a million spermatozoa. (Leeuwenhoek to William Brouncker, November 1677, ibid., pp. 286–287.)

  30. See Adelmann, Marcello Malpighi, II, 730 ff.

  31. Alexander Ross, Arcana Microcosmi, (London: Tho. Newcomb, 1652), p. 230; Adelmann, Marcello Malpighi, II, 913.

    Google Scholar 

  32. [Nehemiah Grew], “Auctoris ad Observatorem Responsum,” Phil. Trans., 142 (December 1678–February 1679), 1043. Regarding Grew's identity as the author of this response, see Leeuwenhoek to Nehemiah Grew, 18 March 1678, in Leeuwenhoek, A.d.B., II, 326–333.

  33. Jacques Roger, Les Sciences de la vie dans la pensée française du XVIIIe siècle, 2nd ed. (Paris: Armand Colin, 1971), pp. 53–63.

    Google Scholar 

  34. René Descartes, “Primae cogitationes circa generationem animalium et nonnulla de saporibus”, in Oeuvres, ed. Charles, Adam and Paul, Tannery (Paris: Léopold Cerf, 1897–1910), XI, 506–508; Henricus Regius, Medicina, et praxis medica, medicationum exemplis demonstrata, 3rd ed. (Utrecht: Theodorus ab ackersdijck, 1668), p. 54; Gilbertus Jacchaeus, Institutiones medicae, 3rd ed. (Leiden: Joannes Maire, 1653), p. 84; Anton Deusing, Synopsis medicinae universalis (Groningen: Joannes Nicolai, 1649), p. 129; idem, Idea fabricae corporis humani (Groningen: Franciscus Bronchorstius, 1659), p. 140; Ysbrand van Diemerbroeck, Anatomes corporis humani in Opera omnia, ed. Timannus de Diemerbroeck (Utrecht: Meinardus à Dreunen & Guilielmus à Walcheren, 1685), p. 130. See also de Graaf, Tractatus de virorum organis, p. 91. Aristotle's contention that blood played a role in conception was still echoed at times in the Netherlands as well: Deusing, Synopsis medicinae universalis, p. 130; Gerard Blaes (Blasius), Medicina generalis, novâ accuratâque methodo fundamenta exhibens (Amsterdam: Petrus van den Berge, 1661), p. 102.

    Google Scholar 

  35. Anton Deusing, Genesis microcosmi [2nd ed.] (Amsterdam: Petrus van den Berge, 1665), pp. 53–54; Idea fabricae corporis humani, p. 140. On the Aristotelian background and seventeenth-century development of the idea of a spiritous or ethereal fecundating principle in the semen, see Carlo Castellani, “Origini ed evoluzione della teoria della ≪aura seminalis≫ da Fabrici d'Acquapendente a Marcello Malpighi”, Episteme, 1 (1967), 173–196.

    Google Scholar 

  36. William Harvey, Exercitationes de generatione animalium (London: Typis Du-Gardianis, impensis Octaviani Pulleyn, 1651), p. 137.

    Google Scholar 

  37. William Harvey, Exercitationes de generatione animalium (London: Typis Du-Gardianis, impensis Octaviani Pulleyn, 1651), pp. 226–229.

    Google Scholar 

  38. William Harvey, Exercitationes de generatione animalium (London: Typis Du-Gardianis, impensis Octaviani Pulleyn, 1651), pp. 229–231.

    Google Scholar 

  39. Anthony Everaerts, Novus et genuinus hominis brutique animalis exortus (Middelburg: Franciscus Kroock, 1661), pp. 31–32, 35, 51; Regnier de Graaf, De mulierum organis generationi inservientibus tractatus novus, in Opera omnia, p. 397.

    Google Scholar 

  40. William Harvey, Exercitationes de generatione animalium (London: Typis Du-Gardianis, impensis Octaviani Pulleyn, 1651), p. 228.

    Google Scholar 

  41. Nicolaus Steno, “Historia dissecti piscis ex canum genere,“ in Elementorum myologiae specimen, seu musculi descriptio geometrica (Florence: ex typographia sub signo Stellae, 1667), pp. 117–118; Johannes van Horne, Suarum circa partes generationis in utroque sexu observationum prodromus (Leiden: Gaasbekios, 1668), p. [8]; Jan Swammerdam, Miraculum naturae (Leiden: Severinus Matthaei, 1672), pp. 19–20, 45; de Graaf, De mulierum organis, pp. 298, 302–303. The Leiden circle was apparently anticipated by several years, however, by Willem Langly, physician at Dordrecht; see Justus Schraderus, Observationes et historiae omnes & singulae e Guiljelmi Harvei libello De generatione animalium excerptae (Amsterdam: Abrahamus Wolfgang, 1674), “Praefatio,” pp. [xiv]-[xv].

    Google Scholar 

  42. Jan Swammerdam, Bybelder Natuure (Leiden: Isaak Severinus, Boudewyn Vander Aa, Pieter Vander Aa, 1737–1738), I, 305; idem, Miraculum naturae, pp. 20, 54–55. Elsewhere Swammerdam wrote that the human “egg” was first known in 1667. (Jan Swammerdam, Ephemeri vita [Amsterdam: Abraham Wolfgang, 1675], pp. 9–10.)

    Google Scholar 

  43. Swammerdam, Miraculum naturae, pp. 19, 22–23; Ysbrand van Diemerbroeck (Anatome corporis humani, plurimis novis inventis instructa [Utrecht: Meinardus à Dreunen, 1672], p. 218), offered other contrary arguments.

  44. Jan Swammerdam, Bybelder Natuure (Leiden: Isaak Severinus, Boudewyn Vander Aa, Pieter Vander Aa), II, 802, 804–805.

  45. De Graaf, De mulierum organis, pp. 348–349, 400–401.

  46. Diemerbroeck, Anatomes corporis humani in Opera omnia, p. 131. Compare with the citation in note 43. Diemerbroeck died in 1674.

  47. [Theodorus Craanen], “Exortus sive generatio hominis novus & genuinus,” Oeconomia animalis ad circulationem sanguinis breviter delineata (Gouda: Guilhelmus vander Hoeve, 1685), p. 5; Diemerbroeck, Anatomes corporis humani in Opera omnia, pp. 132, 159, 163, 168, 179, 220; Steven Blanckaert, Medicinae institutiones, in Opera medica, theoretica, practica et chirurgica (Leiden: Cornelius Boutestein & Jordanus Lugtmans, 1701), I, 219, 273; Wolferdus Senguerdius, Philosophia naturalis, 2nd ed. (Leiden: Danieles à Gaesbeeck, 1685), p. 399; de Graaf, Tractatus de virorum organis, pp. 88, 92–93; idem, De mulierum organis, pp. 346–347; Swammerdam, Bybel der Natuure, II, 514–517; Antony Nuck, Adenographia curiosa et uteri foeminei anatome nova (Leiden: Jordanus Luchtmans, 1691), p. 69.

    Google Scholar 

  48. Leeuwenhoek to Nehemiah Grew, 18 March 1678, in Leeuwenhoek, A.d.B., II, 334–335.

  49. [Grew], “Auctoris ad Observatorem Responsum,” p. 1043.

  50. Leeuwenhoek to Nehemiah Grew, 18 March 1678, in Leeuwenhoek, A.d.B., II, 342–343. Swammerdam publicized a human uterus he had prepared as an example of his injected wax technique and also kept some preserved human “eggs” in his cabinet. (Swammerdam, Miraculum naturae, pp. 37–38, 46; Ephemeri vita, p. 10; Bybel der Nature, I, 305.) Regarding the uterus and other prepared items, see also Swammerdam to Henry Oldenburg, 5 April 1672, in Oldenburg, Correspondence, VIII, 617–618; Oldenburg to Swammerdam, 19 December 1672 [O.S.], ibid., IX, 367–369; and Swammerdam to Oldenburg, 24 January 1673, ibid., pp. 411–413. De Graaf also made such anatomical preparations. (See Oldenburg to Swammerdam, 24 April 1672 [O.S.], ibid., IX, 40, 42; Regnier de Graaf to Oldenburg, 12 July 1672, ibid., pp. 137–138.)

  51. Leeuwenhoek to the Royal Society, 19 Marcy 1694, in Leeuwenhoek, Vierde Vervolg der Brieven (Delft: Henrik van Kroonevelt, 1694), pp. 670–671.

  52. I have been able to locate no Dutch translation of de Graaf's De mulierum organis generationi inservientibus tractatus novus earlier than that in his posthumous Alle de Wercken (Amsterdam: Abraham Abrahamse), published in 1686. Nor have I been able to find a Dutch translation of Harvey's Exercitationes de generatione animalium.

  53. De Graaf, Tractatus de virorum organis, “Praefatio,” pp. [vi]-[vii]; De mulierum organis, pp. 158, 411.

  54. When Leeuwenhoek speaks of de Graaf's having discussed such matters with mutual acquaintances (with medical training), he never suggests that de Graaf had spoken of them to Leeuwenhoek himself. See Leeuwenhoek to the Royal Society, 30 March 1685, in Leeuwenhoek, A.d.B., V, 170–171; Leeuwenhoek to the Royal Society, 19 March 1694, in Leeuwenhoek, Vierde Vervolg, pp. 670–671.

  55. Leeuwenhoek to Robert Hooke, 14 January 1678, in Leeuwenhoek, A.d.B., II, 310–313; Leeuwenhoek to the Royal Society, 30 March 1685, ibid., V, 159–161. See also Leeuwenhoek to Nehemiah Grew, 18 March 1678, ibid., II, 332–336.

  56. Leeuwenhoek to Nehemiah Grew, 18 March 1678, ibid., II, 342–347.

  57. Ibid., pp. 342–343; Swammerdam, Miraculum naturae, facing p. 34; A. Schierbeek, Jan Swammerdam: Zijn Leven en zijn Werken (Lochem: “De Tijdstroom,” [1946]), p. 114 and plate 5, facing p. 48. See also Gerard Blaes (Blasius), Ontleeding des menschelyken Lichaems (Amsterdam: Abraham Wolfgangh, 1675), plate 17, fig. 1; Steven Blanckaert, De nieuw hervormde Anatomie [2nd ed.] (Amsterdam: Jan ten Hoorn, 1686), p. 463.

  58. Leeuwenhoek to Christopher Wren, 22 January 1683, in Leeuwenhoek, A.d.B., IV, 12–13; Leeuwenhoek to the Royal Society, 30 March 1685, ibid., V, 162–169, 188–191, 194–197. Leeuwenhoek was later aware that both de Graaf and Malpighi had identified the ovarian follicle as the source of the ovum but not the ovum itself (Leeuwenhoek to the Royal Society, 19 March 1694, in Leeuwenhoek, Vierde Vervolg, pp. 659–660) but he did not alter his argument. (Leeuwenhoek to Gottfried Wilhelm Leibniz, 19 May 1716, in Leeuwenhoek, Send-Brieven, pp. 210–211; Leeuwenhoek to Gottfried Wilhelm Leibniz, 17 November 1716, ibid., p. 301.) Regarding Malpighi, see Marcello Malpighi, “Praeclarissimo & eruditissimo Viro D. Jacobo Sponio...,” Phil. Trans., 161 (20 July 1684), 637–641; Adelmann, Marcello Malpighi, II, 853, 859. With respect to de Graaf, see note 45.

  59. Leeuwenhoek to the Royal Society, 19 March 1694, in Leeuwenhoek, Vierde Vervolg, pp. 663, 669–670; Leeuwenhoek to Gottfried Wilhelm Leibniz, 19 May 1716, in Leeuwenhoek, Send-Brieven, p. 211; Leeuwenhoek to Gottfried Wilhelm Leibniz, 17 November 1716, ibid., p. 304. See also Leeuwenhoek to the Royal Society, 30 March 1685, in Leeuwenhoek, A.d.B., V, 204–205; Leeuwenhoek to the Royal Society, 13 July 1685, ibid., pp. 248–249; Leeuwenhoek to the Royal Society, 10 June 1686, ibid., VI, 120–123. Leeuwenhoek did believe, however, that the nourishment provided by the female in the uterus could alter the animal considerably. (Leeuwenhoek to the Royal Society, 13 July 1685, ibid., V, 250–251.)

  60. Leeuwenhoek to the Royal Society, 30 March 1685, in Leeuwenhoek, A.d.B., V, 158–159, 164–165, 170–171; Leeuwenhoek to the Royal Society, 10 June 1686, ibid., VI, 122–123; Leeuwenhoek to the Royal Society, 19 March 1694, in Leeuwenhoek, Vierde Vervolg, p. 666.

  61. [Grew], “Auctoris ad Observatorem Responsum,” p. 1043; Leeuwenhoek to Nehemiah Grew, 18 March 1678, in Leeuwenhoek, A.d.B., II, 326–327, 340–349; Leeuwenhoek to Nehemiah Grew, 21 February 1679, ibid., pp. 418–421.

  62. Leeuwenhoek to Nehemiah Grew, 25 April 1679, in Leeuwenhoek, A.d.B., III, 18–19.

  63. Leeuwenhoek to Nehemiah Grew, 18 March 1678, ibid., II, 340–341.

  64. Ibid.; Leeuwenhoek to Nehemiah Grew, 21 February 1679, ibid., pp. 418–421.

  65. Leeuwenhoek to Nehemiah Grew, 18 March 1678, ibid., pp. 328–329. For example, also see (apart from Leeuwenhoek's initial letter to Lord Brouncker) ibid., pp. 338–341; Leeuwenhoek to Nehemiah Grew, 25 April 1679, ibid., III, 10–11.

  66. Leeuwenhoek to Nehemiah Grew, 25 April 1679, ibid., III, 8–9.

  67. Ibid.

  68. Ibid., pp. 8–11.

  69. Ibid., pp. 10–19; his conclusion is on pp. 18–19.

  70. Ibid., pp. 18–21.

  71. Ultimately he completely repudiated his former accounts of the vessels in the semen (Leeuwenhoek to Christopher Wren, 22 January 1683, ibid., IV, 8–11) concerning which he had once told the Royal Society he expected them to trust him. (Leeuwenhoek to Nehemiah Grew, 18 March 1678, ibid., II, 336–339.)

  72. Leeuwenhoek to Nehemiah Grew, 25 April 1679, ibid., III, 10–19; Leeuwenhoek to Robert Hooke, 5 April 1680, ibid., pp. 202–209; Leeuwenhoek to Robert Hooke, 12 November 1680, ibid., pp. 314–325, 330–331.

  73. Leeuwenhoek to Robert Hooke, 12 November 1680, ibid., pp. 324–329.

  74. Leeuwenhoek to Christopher Wren, 22 January 1683, ibid., IV, 10–11.

  75. [Grew], “Auctoris ad Observatorem Responsum,” p. 1043.

  76. Leeuwenhoek to Nehemiah Grew, 18 March 1678, in Leeuwenhoek, A.d.B., II, 332–335.

  77. Leeuwenhoek to the Royal Society, 5 January 1685, ibid., V, 66–67; Leeuwenhoek to the Royal Society, 23 January 1685, ibid., pp. 136–137; Leeuwenhoek to the Royal Society, 30 March 1685, ibid., pp. 154–155, 168–169.

  78. Leeuwenhoek to the Royal Society, 30 March 1685, ibid., pp. 142–145, 184–189, 194–199; Leeuwenhoek to Christopher Wren, 16 July 1683, ibid., IV, 64–69; Leeuwenhoek to the Royal Society, 10 June 1686, ibid., VI, 112–113; Leeuwenhoek to the Royal Society, 11 July 1687, ibid., pp. 316–319.

  79. Leeuwenhoek to Christopher Wren, 16 July 1683, ibid., IV, 58–59; Leeuwenhoek to the Royal Society, 30 March 1685, ibid., V, 178–179; Leeuwenhoek to the Royal Society, 13 July 1685, ibid., pp. 248–249; Leeuwenhoek to the Royal Society, 7 September 1688, ibid., VIII, 14–15.

  80. Leeuwenhoek to Christopher Wren, 16 July 1683, ibid., IV, 66–69; Leeuwenhoek to the Royal Society, 10 June 1686, ibid., VI, 104–105, 110–113, 116–117; Leeuwenhoek to the Royal Society, 11 July 1687, ibid., pp. 314–315; Leeuwenhoek to the Royal Society, 2 March 1694, in Leeuwenhoek, Vierde Vervolg, p. 651.

  81. Leeuwenhoek to the Royal Society, 11 July 1687, in Leeuwenhoek, A.d.B., VI, 316–319.

  82. Leeuwenhoek to the Royal Socieyt, 10 June 1686, ibid., pp. 112–113.

  83. Ibid., pp. 114–117. In 1695 he also wrote of having observed in the transparent fluid of early mussel eggs an abundance of small animalcules that he took for spermatozoa. (Leeuwenhoek to the Elector Palatine, 18 September 1695, in Leeuwenhoek, Vijde Vervolg, p. 147.) The first observations of spermatozoa penetrating and within an ovum did not come until the nineteenth century. See F. J. Cole, Early Theories of Sexual Generation (Oxford: Clarendon Press, 1930), pp. 193–195; Charles W. Bodemer, “The Microscope in Early Embryological Investigation,” Gynecol. Invest., 4 (1973), 204–205. The mammalian ovum had itself been observed for the first time only shortly before. See George Sarton, “The Discovery of the Mammalian Egg and the Foundation of Modern Embryology”, Isis, 16 (1931), 315–[378].

  84. Leeuwenhoek to the Royal Society, 30 March 1685, in Leeuwenhoek, A.d.B., V, 198–199. See also Leeuwenhoek to Christopher Wren, 22 January 1683, ibid., IV, 10–13.

  85. Leeuwenhoek to the Royal Society, 30 March 1685, ibid., V, 198–201; de Graaf, De mulierum organis, pp. 400–401; H. D. Jocelyn and B. P. Setchell, notes to Regnier de Graaf on the Human Reproductive Organs (J. Reproduct. Fert. suppl. no. 17; Oxford, etc.: Blackwell Scientific Publications, 1972), 206n275.

  86. Leeuwenhoek to the Royal Society, 13 July 1685, in Leeuwenhoek, A.d.B., V, 246–247; Leeuwenhoek to the Royal Society, 6 August 1687, ibid., VII, 34–35; Leeuwenhoek to the Royal Society, 12 January 1689, ibid., VIII, 110–111; Leeuwenhoek to Antonio Magliabechi, 18 September 1691, ibid., pp. 176, 184–185; Leeuwenhoek to the Royal Society, 7 March 1692, ibid., pp. 328–329. See also Leeuwenhoek to Antoni Cink, 24 October 1713, in Leeuwenhoek, Send-Brieven, p. 88.

  87. Leeuwenhoek to the Royal Society, 30 March 1685, in Leeuwenhoek, A.d.B., V, 176–179; Leeuwenhoek to the Royal Society, 13 July 1685, ibid., pp. 248–249, 266–267.

  88. Leeuwenhoek to the Royal Society, 30 March 1685, ibid., 176–179. See also Leeuwenhoek to the royal Society, 11 July 1687, ibid., VI, 330–331.

  89. Leeuwenhoek to Nehemiah Grew, 18 March 1678, ibid., II, 340–341; Leeuwenhoek to Nehemiah Grew, 27 September 1678, ibid., pp. 390–391; Leeuwenhoek to Constantijn Huygens, 20 May 1679, ibid., III, 56–67; Leeuwenhoek to Robert Hooke, 3 March 1682, ibid., pp. 396–397; Leeuwenhoek to the Royal Society, 25 July 1684, ibid., IV, 274–275; Leeuwenhoek to the Royal Society, 5 January 1685, ibid., V, 20–21.

  90. Leeuwenhoek to Nehemiah Grew, 25 April 1679, ibid., III, 20–21.

  91. Leeuwenhoek's comment footnoted immediately above might suggest that he already had in mind the idea of a preformed man in the spermatozoa, although elsewhere he similarly equated the complexity of microscopic animals in general with that of larger animals, including the human body. (Leeuwenhoek to Robert Hooke, 3 March 1682, ibid., pp. 396–397; Leeuwenhoek to Constantijn Huygens, 20 May 1679, ibid., pp. 58–59.) Thus no implications beyong a simple emphasis on the complexity of the spermatozoa can be ascribed with confidence to the cited passage. In 1683 Leeuwenhoek wrote that the inner body of the spermatozoa acquired the form of a man as “a whole other nature” (een geheel ander wesen) that is already provided with the heart and entrails, “indeed, all the perfection,” of a man. (Leeuwenhoek to Christopher Wren, 22 January 1683, ibid., IV, 16–17.) Whether the spermatozoa had all that perfection before assuming their new nature, however, is not clear.

  92. Leeuwenhoek to the Royal Society, 13 July 1685, ibid., V, 236–237.

  93. See Leeuwenhoek to the Royal Society, 30 March 1685, ibid., pp. 182–185.

  94. Leeuwenhoek explicitly denied that plants mated. (Leeuwenhoek to the Royal Society, 13 July 1685, ibid., pp. 232–235, 246–247; Leeuwenhoek to the Royal Society, 10 June 1686, ibid., VI, 120–121.) On the spreading recognition of plant sexuality in the 1690s and earlier, see Conway Zirkle, introduction to The Anatomy of Plants by Nehemiah Grew, Sources of Science, No. 11 (London: W. Rawlins, 1682; reprint ed., New York: Johnson Reprint Corporation, 1965), pp. xiv–xvi.

  95. Leeuwenhoek to the Royal Society, 13 July 1685, in Leeuwenhoek, A.d.B., V, 230–239; Leeuwenheok to the Royal Society, 12 October 1685, ibid., pp. 308–309; Leeuwenhoek to the Royal Society, 10 June 1686, ibid., VI, 120–121; Leeuwenhoek to the Royal Society, 10 July 1696, in Leeuwenhoek, Sesde Vervolg, p. 279; Leeuwenhoek to the Royal Socieyt, 23 June 1699, in Leeuwenhoek, Sevende Vervolg, p. 102; Leeuwenhoek to the Royal Society, 26 February 1703, Leeuwenhoek Letters, Royal Society Library, London, EL.L3.51, fols. 239v–240r. Cf. Leeuwenhoek to Christopher Wren, 16 July 1683, in Leeuwenhoek, A.d.B., IV, 66–67.

  96. Leeuwenhoek to the Royal Society, 13 July 1685, in Leeuwenhoek, A.d.B., V, 236–237, 262–264.

  97. See Guiseppe degli Aromatari, “An Epistle Writ by Josephus de Aromatariis Concerning the Seeds of Plants, and Generation of Animals,” Phil. Trans., 211 (June 1694), 150–152; Antonius de Heyde, annotations in Nieuw lichtende Fakkel der Chirurgie of hedendaagze Heel-Konst by Cornelis vande Voorde (Middelburg: Wilhelmus Goeree, 1680), 224n6; George Garden, “A Discourse Concerning the Modern Theory of Generation,” Phil. Trans., 192 (January-February 1691), 476.

    Google Scholar 

  98. Leeuwenhoek to the Royal Society, 30 March 1685, in Leeuwenhoek, A.d.B., V, 208–211; Leeuwenhoek to the Royal Society, 13 July 1685, ibid., pp. 218–223, 230–231, 258–259; Leeuwenhoek to the Royal Society, 13 June 1687, ibid., VI, 252–309; Leeuwenhoek to Antonie Heinsius, 1 May 1695, in Leeuwenhoek, Vijfde Vervolg, pp. 44–45, 53. Leeuwenhoek usually made no distinction between the cotyledons and ordinary leaves (W. K. H. Karstens, annotation in Leeuwenhoek, A.d.B., V, 218–219n4; 224–225nn16, 13), but see Leeuwenhoek to the Royal Society, 13 July 1685, in Leeuwenhoek, A.d.B., V, 258–259.

  99. Leeuwenhoek to the Royal Society, 13 July 1685, in Leeuwenhoek, A.d.B., V, 220–223; Leeuwenhoek to the Royal Society, 13 June 1687, ibid., VI, 308–309; Leeuwenhoek to Antonie Heinsius, 1 May 1695, in Leeuwenhoek, Vijfde Vervolg, p. 45.

  100. Leeuwenhoek to Gottfried Wilhelm Leibniz, 18 November 1715, in Leeuwenhoek, Send-Brieven, p. 179.

  101. Ibid., p. 177.

  102. Ibid., p. 176; Leeuwenhoek to Antonie Heinsius, 1 May 1695, in Leeuwenhoek, Vijfde Vervolg, p. 53; Leeuwenhoek to the Royal Society, 26 February 1703, Leeuwenhoek Letters, Royal Society Library, London, EL.L3.51, fol. 234r. Regarding his insistence that later organic forms had to be within the immediately antecedent forms, see also Leeuwenhoek to the Royal Society, 9 June 1699, in Leeuwenhoek, Sevende Vervolg, pp. 95–96; Leeuwenhoek to the Royal Society, 23 June 1699, ibid., p. 103; Leeuwenhoek to Hans Sloane, 25 Dec. 1700, ibid., pp. 305–306; Leeuwenhoek to “Hoog Doorlugtige Furst...,” 20 April 1702, ibid., p. 450; Leeuwenhoek to the Royal Society, 26 February 1703, Leeuwenhoek Letters, Royal Society Library, London, EL.L3.51, fol. 238v.

  103. Leeuwenhoek to Antonie Heinsius, 1 May 1695, in Leeuwenhoek, Vijfde Vervolg, p. 57; Leeuwenhoek to the Royal Society, 10 July 1696, in Leeuwenhoek, Sesde Vervolg, pp. 278, 280; Leeuwenhoek to the Royal Society, 23 June 1699, in Leeuwenhoek, Sevende Vervolg, p. 103; Leeuwenhoek to the Royal Society, 26 February 1703, Leeuwenhoek Letters, Royal Society Library, London, EL.L3.51, fol. 238v.

  104. Leeuwenhoek to the Royal Society, 24 August 1688, in Leeuwenhoek, A.d.B., VII, 372–387.

  105. Ibid., pp. 384–387.

  106. Leeuwenhoek to the Royal Society, 13 July 1685, ibid., V, 236–237.

  107. Leeuwenhoek to Antonie Heinsius, 1 May 1695, in Leeuwenhoek, Vijfde Vervolg, pp. 53, 57; Leeuwenhoek to the Royal Society, 9 June 1699, in Leeuwenhoek, Sevende Vervolg, pp. 95–96; Leeuwenhoek to the Royal Society, 23 June 1699, ibid., p. 105. See also Leeuwenhoek to the Royal Society, 26 February 1703, Leeuwenhoek Letters, Royal Society Library, London, EL.L3.51, fols 239v–240r.

  108. Leeuwenhoek to “Hoog Doorlugtige Furst...,” 20 April 1702, in Leeuwenhoek, Sevende Vervolg, p. 450.

  109. Leeuwenhoek to the Royal Society, 13 July 1685, in Leeuwenhoek, A.d.B., V, 236–237.

  110. Leeuwenhoek to Christopher Wren, 22 January 1683, ibid., IV, 16–17; Leeuwenhoek to Hans Sloane, 25 December 1700, in Leeuwenhoek, Sevende Vervolg, p. 305.

  111. Leeuwenhoek to the Royal Society, 9 June 1699, in Leeuwenhoek, Sevende Vervolg, pp. 92–95 (the relevant plate, which has been placed in the body of the wrong letter, is found facing p. 68). Concerning this hoax by Plantade (Dalenpatius), see Cole, Early Theories of Sexual Generation, pp. 68–72.

  112. Leeuwenhoek to Christopher Wren, 16 July 1683, in Leeuwenhoek, A.d.B., IV, 64–67.

  113. Leeuwenhoek to the Royal Society, 11 July 1687, ibid., VI, 318–321.

  114. Leeuwenhoek to Frederik Adriaan, Baron van Reede, 20 February 1696, in Leeuwenhoek, Sesde Vervolg, p. 203; Leeuwenhoek to the Royal Society, 21 June 1701, in Leeuwenhoek, Sevende Vervolg, pp. 352, 362–363.

  115. Jan Swammerdam, Bybelder Natuure (Leiden: Isaak Severinus, Boudewyn Vander Aa, Pieter Vander Aa, 1737–1738), II, 813–819.

    Google Scholar 

  116. Leeuwenhoek to the Royal Society, 7 September 1688, in Leeuwenhoek, A.d.B., VIII, 10–15.

  117. Leeuwenhoek to the Royal Society, 9 June 1699, in Leeuwenhoek, Sevende Vervolg, p. 92.

  118. Leeuwenhoek to Nehemiah Grew, 18 March 1678, in Leeuwenhoek, A.d.B., II, 346–349 and “Table” XVI; Arthur Hughes, “Studies in the History of Microscopy. 1. The Influence of Achromatism,” J. Roy. Micros. Soc., ser. 3, 75 (1955), 15.

  119. Leeuwenhoek to Nehemiah Grew, 18 March 1678, in Leeuwenhoek, A.d.B., II, 348–349.

  120. Leeuwenhoek to Nehemiah Grew, 31 May 1678, ibid., pp. 362–363; Leeuwenhoek to the Royal Society, 15 April 1701, in Leeuwenhoek, Sevende Vervolg, pp. 321, 323.

  121. Leeuwenhoek to the Royal Society, 9 June 1699, in Leeuwenhoek, Sevende Vervolg, pp. 99–100. He sometimes observed them by candlelight, with a small concave metal mirror to enhance the illumination. Though he would on occasion use a “very good and very magnifying” microscope in his observations of spermatozoa (Leeuwenhoek to the Royal Society, 6 August 1687, in Leeuwenhoek, A.d.B., VII, 10–13), he could show them to visitors through an “ordinary” (gemeen) instrument. (Leeuwenhoek to Robert Hooke, 13 October 1679, ibid., III, 108–109.)

  122. Leeuwenhoek to the Royal Society, 15 April 1701, in Leeuwenhoek, Sevende Vervolg, p. 325.

  123. Leeuwenhoek to the Royal Society, 30 March 1685, in Leeuwenhoek, A.d.B., V, 190–193 and “Table” XX, figs. 33 and 34. (See also the drawings of dead spermatozoa included with his letter of 18 March 1678 to Nehemiah Grew, ibid., II, “Table” XVI.) Leeuwenhoek to the Elector Palatine, 18 September 1695, in Leeuwenhoek, Vijfde Vervolg, p. 146; Leeuwenhoek to the Royal Society, 9 June 1699, in Leeuwenhoek, Sevende Vervolg, pp. 98–99; Leeuwenhoek to Hans Sloane, 25 December 1700, ibid., pp. 301–302 and figs. 2–6 in plate facing p. 300; Leeuwenhoek to the Royal Society, 15 April 1701, ibid., p. 322.

  124. Leeuwenhoek to the Royal Society, 30 March 1685, in Leeuwenhoek, A.d.B., V, 190–191; Leeuwenhoek to the Royal Society, 13 July 1685, ibid., pp. 236–237.

  125. Leeuwenhoek to Antonie Heinsius, 1 May 1695, in Leeuwenhoek, Vijfde Vervolg, pp. 53–54. Concerning the great secret, see also notes 126 and 127 below, as well as Leeuwenhoek to the Royal Society, 23 June 1699, in Leeuwenhoek, Sevende Vervolg, p. 105.

  126. Leeuwenhoek to the Royal Society, 9 June 1699, in Leeuwenhoek, Sevende Vervolg, p. 96.

  127. Leeuwenhoek to Hans Sloane, 25 December 1700, ibid., p. 306; Leeuwenhoek to the Royal Society, 26 February 1703, Leeuwenhoek Letters, Royal Society Library, London, EL.L3.51, fol. 240v.

  128. Jan Swammerdam, Historia insectorum generalis (Utrecht: Meinardus van Dreunen, 1669), p. 51 in the first series in the pagination. (See also Swammerdam's Miraculum naturae, pp. 21–22; Bybel der Natuure, I, 34.) Nicolas Malebranche, La Recherche de la vérité, in Oeuvres complètes, dir. André Robinet (Paris: J. Vrin, 1958–1970), I, 81–83. (See also Malebranche, Entretiens sur la métaphysique et sur la religion, ibid., XII, 228–229.)

    Google Scholar 

  129. Jacques Roger, Les Sciences de la vie dans la pensée française du XVIIIe siècle, 2nd ed. (Paris: Armand Colin, 1971), pp. 334–353, 364–384, 724, 731–732, 742.

    Google Scholar 

  130. See Cole, Early Theories of Sexual Generation, chaps. 4 and 5.

  131. Malebranche, La Recherche de la vérité, p. 82. This book was translated into Dutch in 1680–1681 (Geneviève Rodis-Lewis, introduction to La Recherche de la vérité, p. xix), though there is no evidence that Leeuwenhoek actually read parts of it; nor is it likely that such an abstract theological and philosophical work would have interested him. Nonetheless, it is very probable that Leeuwenhoek was informed of some of Malebranche's arguments and illustrations. He had often heard, wrote Leeuwenhoek in 1685, that the flower itself could be seen within the tulip bulb—which he denied (Leeuwenhoek to the Royal Society, 12 October 1685, in Leeuwenhoek, A.d.B., V, 302–303) — an observation that had played a prominent role in Malebranche's initial presentation of the idea of a series of encapsulated organisms, an emboîtement. (Malebranche, La Recherche de la vérité, p. 82.) Leeuwenhoek was familiar with Swammerdam's Historia insectorum, which had been written in Dutch (see Leeuwenhoek to Henry Oldenburg, 5 October 1677, in Leeuwenhoek, A.d.B., II, 250–253; Leeuwenhoek to the Royal Society, 24 August 1688, ibid., VII, 344–345, 350–351; Leeuwenhoek to the Royal Society, 7 September 1688, ibid., VIII, 14–17), but Swammerdam's remarks about preexistent animals were brief and vague.

  132. Leeuwenhoek to Lambert van Velthuysen, 13 June 1679, in Leeuwenhoek, A.d.B., III, 76–77; Leeuwenhoek to Lambert van Velthuysen, 11 July 1679, ibid., pp. 86–87.

  133. Leeuwenhoek to the Royal Society, 6 August 1687, ibid., VII, 34–35; Leeuwenhoek to the Royal Society, 24 June 1692, in Leeuwenhoek, Derde Vervolg, p. 474; Leeuwenhoek to Frederik Adriaan, Baron van Reede, 20 August 1695, in Leeuwenhoek, Vijfde Vervolg, p. 135; Leeuwenhoek to the Royal Society, 23 June 1699, in Leeuwenhoek, Sevende Vervolg, pp. 103, 105; Leeuwenhoek to the directors of the East India Company in Delft, 5 August 1699, ibid., p. 111; Leeuwenhoek to Antonio Magliabechi, 16 October 1699, ibid., pp. 149–150; Leeuwenhoek to Nicolaas Boogaart, 14 January 1700, ibid., p. 180; Leeuwenhoek to the Royal Society, 26 February 1703, Leeuwenhoek Letters, Royal Society Library, London, EL.L3.51, fol. 238v; Leeuwenhoek to the Royal Society, 22 September 1711, ibid., EL.L4.40, fol. 152r.

  134. Leeuwenhoek to the Royal Society, 6 August 1687, in Leeuwenhoek, A.d.B., VII, 34–35; Leeuwenhoek to the Royal Society, 24 August 1688, ibid., p. 378.

  135. Leeuwenhoek to the Royal Society, 13 June 1687, ibid., VI, 308–309.

  136. Leeuwenhoek to the Royal Society, 13 July 1685, ibid., V, 264–267; Leeuwenhoek to the Royal Society, 24 August 1688, ibid., VII, 384–387.

  137. Concerning the seeds being already enclosed within the preceding seed, see also Leeuwenhoek to the Royal Society, 26 February 1703, Leeuwenhoek Letters, Royal Society Library, London, EL.L3.51, fol. 238v.

  138. Leeuwenhoek to Lambert van Velthuysen, 13 June 1679, in Leeuwenhoek, A.d.B., III, 78–79.

  139. Ibid., pp. 80–81.

  140. Leeuwenhoek to Robert Hooke, 5 April 1680, ibid., pp. 204–205.

  141. See the following: Regius, Medicina et praxis medica, p. 54; Blaes, Medicina generalis, p. 67; Diemerbroeck, Anatome corporis humani, p. 193; idem, Anatomes corporis humani in Opera omnia, pp. 106, 110–111, 159–160; de Graaf, Tractatus de virorum organis, pp. 56–60, 92 (cf. 54–55); Senguerdius, Philosophia naturalis, p. 399; Nicolaas Hartsoeker, Suite des conjectures physiques (Amsterdam: Henri Desbordes, 1708), pp. 82, 107. But see also Everaerts, Novus et genuinus hominis brutique animalis exortus, pp. 2–6.

  142. See Edward G. Ruestow, “The Rise of the Doctrine of Vascular Secretion in the Netherlands”, J. Hist. Med. Allied Sci., 35 (1980), 272ff.

  143. Frederik Ruysch, “Responsio”, in Abraham Vater, Epistola gratulatoria (Amsterdam: Janssonio-Waesbergios, 1727), p. 12; Herman Boerhaave, Institutiones medicae, 5th ed. (Leiden: Theodorus Haak, Samuel Luchtmans, & Joh. & Herm. Verbeek; Rotterdam: Joan. Dan. Beman, 1734), pp. 326–327; Herman Boerhaave and Frederik Ruysch, Opusculum anatomicum de fabrica glandularum in corpore humano (Leiden: Cornelius Haak, 1751), p. 43.

    Google Scholar 

  144. Leeuwenhoek to Nehemiah Grew, 25 April 1679, in Leeuwenhoek, A.d.B., III, 18–19; Heidentryk Overkamp, Nieuwe Beginselen tot de Genees-en Heel-Konst, 2nd ed. (Amsterdam: Timotheus ten Hoorn, 1686), p. 423; Hartsoeker, Suite des conjectures physiques, p. 107; idem, Recueil de plusieurs pieces de physique (Utrecht: Veuve de G. Broedelet & Fils, 1722), p. 193.

  145. Boerhaave, Institutiones medicae, pp. 342–343; idem, Praelectiones academicae in proprias Institutiones rei medicae edidit, ed. Albrecht von Haller, 2nd ed. (Göttingen: Abram Vandenhoeck, 1740–1744), V, pt. 2, 193; Herman Boerhaave and Albrecht von Haller, Methodus studii medici emaculata (Amsterdam: Jacobus a Wetstein, 1751), I, 251.

  146. Herman Boerhaave to Leeuwenhoek, 10 October 1716, letter published in Luigi Belloni, “Leeuwenhoek, Boerhaave a Bleyswyk sugli spermatozoi”, Physis, 5 (1963), 328; Boerhaave, Praelectiones academicae, V, pt. 1, 350–352, 379.

  147. Leeuwenhoek to Herman Boerhaave, 5 November 1716, in Leeuwenhoek, Send-Brieven, p. 290; Leeuwenhoek to Herman Boerhaave, 21 November 1716, ibid., pp. 308–313; letter from Abraham van Bleyswyk to Herman Boerhaave, published undated in Belloni, “Leeuwenhoek, Boerhaave e Bleyswyk”, p. 330; Boerhaave, Praelectiones academicae, V, pt. 1, 352–353.

  148. Boerhaave, Praelectiones academicae, V, pt. 1, 354.

  149. Castellani, “Spermatozoan Biology”, p. 48; John Farley, The Spontaneous Generation Controversy from Descartes to Oparin (Baltimore: Johns Hopkins University Press, 1977), p. 20.

  150. See Farley, The Spontaneous Generation Controversy, pp. 18–19, 21, and passim.

  151. Leeuwenhoek to Nehemiah Grew, 25 April 1679, in Leeuwenhoek, A.d.B., III, 18–19; Leeuwenhoek to Lambert van Velthuysen, ibid., pp. 78–81.

  152. Leeuwenhoek to the Royal Society, 13 July 1685, ibid., V, 263–265.

  153. Leeuwenhoek to Nehemiah Grew, 25 April 1679, ibid., III, 16–19.

  154. Leeuwenhoek to Robert Hooke, 5 April 1680, ibid., pp. 202–205; Leeuwenhoek to the Royal Society, 9 June 1699, in Leeuwenhoek, Sevende Vervolg, p. 100; Leeuwenhoek to Hans Sloane, 25 December 1700, ibid., p. 298; Leeuwenhoek to James Petirer, 18 August 1711, Leeuwenhoek Letters, Royal Society Library, London, EL.L4.38, fols. 140V–141V; Leeuwenhoek to Herman Boerhaave, 5 November 1716, in Leeuwenhoek, Send-Brieven, p. 286; Leeuwenhoek to Herman Boerhaave, 21 November 1716, ibid., p. 310.

  155. Leeuwenhoek to James Petirer, 18 August 1711, Leeuwenhoek Letters, Royal Society Library, London, EL.L4.38, fols, 140V–141V.

  156. Leeuwenhoek to Robert Hooke, 5 April 1680, in Leeuwenhoek, A.d.B., III, pp. 204–205; Leeuwenhoek to Herman Boerhaave, 5 November 1716, in Leeuwenhoek, Send-Brieven, p. 286. However, in 1716 Leeuwenhoek reported finding no developed spermatozoa in the testicles themselves of a ram, though he claimed to have found spermatozoa in various stages of development in the epididymis. (Leeuwenhoek to Herman Boerhaave, 21 November 1716, ibid., pp. 309–310.)

  157. Leeuwenhoek to Herman Boerhaave, 5 November 1716, in Leeuwenhoek, Send-Brieven, pp. 287–290.

  158. See the summary of Leeuwenhoek's letter of 5 November 1716 to Boerhaave published in Belloni, “Leeuwenhoek, Boerhaave e Bleyswyk,” p. 332.

  159. Martin Lister, “An Objection to the New Hypothesis of the Generation of Animals from Animalcula in Semine Masculino,” Phil. Trans., 244 (September 1698), p. 337.

  160. Pierre Lyonet, annotation in Theologie des insectes by Friedrich Christian Lesser, trans. Lyonet (Paris: Hugues-Daniel Chaubert & Laurent Durand, 1745), I, 245.

    Google Scholar 

  161. Leeuwenhoek to the Royal Society, 23 June 1699, in Leeuwenhoek, Sevende Vervolg, p. 102.

  162. Leeuwenhoek to Christopher Wren, 22 January 1683, in Leeuwenhoek, A.d.B., IV, 10–11; Leeuwenhoek to the Royal Society, 30 March 1685, ibid., V, 180–183; Leeuwenhoek to the Royal Society, 23 June 1699, in Leeuwenhoek, Sevende Vervolg, p. 107; Leeuwenhoek to Gottfried Wilhelm Leibniz, 17 November 1716, in Leeuwenhoek, Send-Brieven, p. 299.

  163. Leeuwenhoek to the Elector Palatine, 18 September 1695, in Leeuwenhoek, Vijfde Vervolg, pp. 145–146.

  164. Leeuwenhoek to the Royal Society, 30 March 1685, in Leeuwenhoek, A.d.B., V, 180–183; Leeuwenhoek to Gottfried Wilhelm Leibniz, 17 November 1716, in Leeuwenhoek, Send-Brieven, p. 299.

  165. Leeuwenhoek to the Royal Society, 23 June 1699, in Leeuwenhoek, Sevende Vervolg, p. 106.

  166. Leeuwenhoek to Frederik Adriaan, Baron van Reede, 10 July 1695, in Leeuwenhoek, Vijfde Vervolg, pp. 90, 100. Regarding Leeuwenhoek's observations of aphids, see F. J. Cole, “Microscopic Science in Holland in the Seventeenth Century,” J. Quekett Micros. Club, ser. 4,1 (1938), 61–64; A. Schierbeek, Antoni van Leeuwenhoek, zijn Leven en zijn Werken (Lochem: “De Tijdstroom,” 1950–1951), I, 271–278.

  167. Leeuwenhoek to Frederik Adriaan, Baron van Reede, 10 July 1695, in Leeuwenhoek, Vijfde Vervolg, p. 90; Leeuwenhoek to Hans Sloane, 26 October 1700, in Leeuwenhoek, Sevende Vervolg, p. 283.

  168. Leeuwenhoek spoke of the reproductive cycle of the aphids as the most astonishing instance of propagation he had seen (Leeuwenhoek to Frederik Adriaan, Baron van Reede, 10 July 1695, in Leeuwenhoek, Vijfde Vervolg, p. 90), unique, as far as he knew, to this insect. (Leeuwenhoek to Hans Sloane, 26 October 1700, in Leeuwenhoek, Sevende Vervolg, pp. 282–283.) However, see also note 171 below.

  169. Leeuwenhoek to Hans Sloane, 26 October 1700, in Leeuwenhoek, Sevende Vervolg, p. 282.

  170. Ibid., p. 283. F. J. Cole concluded that Leeuwenhoek looked upon the aphids themselves as spermatic animals. (Cole, “Microscopic Science in Holland,” p. 64.) Against the background of Lister's letter, however, the analogy between the generation of aphids and spermatozoa would seem to have been intended more as a model for the latter than an explanation of the former.

  171. Leeuwenhoek assumed an absence of males and mating in a few other species as well. See Leeuwenhoek to the Royal Society, 10 July 1696, in Leeuwenhoek, Sesde Vervolg, p. 272; Leeuwenhoek to the Royal Society, 26 February 1703, Leeuwenhoek Letters, Royal Society Library, London, EL.L3.51, fol. 240r; Leeuwenhoek to the Royal Society, 21 March 1704, ibid., EL.L3.62, fols. 284r–284v; Leeuwenhoek to Cornelis Spiering, 22 May 1716, in Leeuwenhoek, Send-Brieven, p. 218; Leeuwenhoek to the Royal Society, 22 September 1711, Leeuwenhoek Letters, Royal Society Library, London, EL.L4.40, fol. 153v; Leeuwenhoek to Herman Boerhaave, 5 November 1716, in Leeuwenhoek, Send-Brieven, p. 288; Leeuwenhoek to James Jurin, 1 May 1722, Leeuwenhoek Letters, Royal Society Library, London, EL.L4.69, fol. 273r.

  172. See John R. Baker, Abraham Trembley of Geneva, Scientist and Philosopher, 1770–1784 (London: Edward Arnold, 1952), p. 183; Roger, Les Sciences de la vie, pp. 381–382.

    Google Scholar 

  173. Leeuwenhoek to Frederik Adriaan, Baron van Reede, 10 July 1695, in Leeuwenhoek, Vijfde Vervolg, p. 90.

  174. Leeuwenhoek to the Royal Society, 13 July 1685, in Leeuwenhoek, A.d.B., V, 264; Leeuwenhoek to the Royal Society, 24 August 1688, ibid., VII, 378–380. Stoffe has been translated as “substance” in these passages in A.d.B. and might also have been translated as “matter,” but I have avoided these terms because in the context of the seventeenth century they are too redolent of formal philosophic currents of thought that remained alien to Leeuwenhoek's thinking. He did speak at least once, however, of the wesen (wezen) — “essence,” “substance,” “nature,” or “being” — that was one of the components poured into — or perhaps, after all, made within — the developing fruit and from which came the beginning of the embryo plant in the seed. (Leeuwenhoek to the Royal Society, 13 July 1685, ibid., V, 266.)

  175. See Leeuwenhoek to Frederik Adriaan, Baron van Reede, 20 August 1695, in Leeuwenhoek, Vijfde Vervolg, p. 135; Leeuwenhoek to Antonio Magliabechi, 16 October 1699, in Leeuwenhoek, Sevende Vervolg, pp. 149–150.

  176. Leeuwenhoek to the Royal Society, 13 July 1685, in Leeuwenhoek, A.d.B., V, 264–265.

  177. Ibid., pp. 266–267. Regarding seeds see also Leeuwenhoek to the Royal Society, 24 August 1688, ibid., VII, 378–381.

  178. See also Leeuwenhoek to the Royal Society, 12 August 1692, in Leeuwenhoek, Derde Vervolg, p. 492; Leeuwenhoek to Hans Sloane, 24 December 1700, in Leeuwenhoek, Sevende Vervolg, p. 306; Leeuwenhoek to the Royal Society, 21 June 1701, ibid., p. 360; Leeuwenhoek to the Royal Society, 22 September 1711, Leeuwenhoek Letters, Royal Society Library, London, EL.L4.40, fol. 147v; Leeuwenhoek to Abraham van Bleyswyk, 2 March 1717, in Leeuwenhoek, Send-Brieven, p. 316.

  179. Leeuwenhoek to Robert Hooke, 3 March 1682, in Leeuwenhoek, A.d.B., III, 414–415; Leeuwenhoek to the Royal Society, 14 May 1686, ibid., VI, 50–51.

  180. Leeuwenhoek to the Royal Society, 13 July 1685, ibid., V, 238, 240–241; Leeuwenhoek to the Royal Society, 26 February 1703, Leeuwenhoek Letters, Royal Society Library, London, EL.L3.51, fol. 233v.

  181. Leeuwenhoek to Nicolaas Witsen, 8 March 1696, in Leeuwenhoek, Sesde Vervolg, p. 243. See also Leeuwenhoek to the Royal Society, 26 February 1703, Leeuwenhoek Letters, Royal Society Library, London, EL.L3.51, fol. 234r.

  182. Malebranche noted that the transformation of the egg into a chick was infinitely more difficult than the preservation of a chick that was already entirely formed. (Malebranche, La Recherche de la vérité, in Oeuvres complètes, II, 105.)

  183. Leeuwenhoek to Herman Boerhaave, 26 August 1717, in Leeuwenhoek, Send-Brieven, pp. 404–405.

Download references

Author information

Authors and Affiliations

  1. Department of History, University of Colorado, Boulder, Colorado

    Edward G. Ruestow

Authors
  1. Edward G. Ruestow
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and permissions

About this article

Cite this article

Ruestow, E.G. Images and ideas: Leeuwenhoek's perception of the spermatozoa. J Hist Biol 16, 185–224 (1983). https://doi.org/10.1007/BF00124698

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00124698

Search

Navigation