Reception of Joblot’s work and the academic context

On top of the consideration that Joblot copied Leeuwenhoek’s or Huygens’

experiments,²⁰⁹ historians did not acknowledged any reception of Joblot’s book and ideas during the eighteenth-century, and most ignore him. No evidence has been brought forward that the major microscopists of his time and of the following period --Trembley, Needham, Spallanzani, Hill, Müller-- read or even had knowledge of the book. On the contrary I will defend here four ideas: 1. Joblot’s book received three distinct receptions during the century,²¹⁰ which put his book among the most influential microscopical works of the Enlightenment; 2. The first apparent absence of its reception is due to a good matching of his ideas with those defended in the Paris Académie des sciences, and such reception well illustrates the routine status of the microscope adopted by eighteenth-century scholars; 3. Contrary to previous experiments on spontaneous generation, Joblot’s experiments are the first to be presented within a rationalised experimental system. In such a way, Joblot did not imitate Leeuwenhoek nor Huygens, but improved experimental protocols invented by Huygens and others; 4.

Nevertheless, the absence of a framework that could give meaning to Joblot’s works forced the abandoning of such a topic and turned the attention of microscopists towards more suitable objects, such as insects or seeds.

209 Fournier 1981, 206, Dobell 1932, 372. However, later Fournier (1991, 182-185) changed her mind about Joblot imitating Leeuwenhoek.

210 I examine in this chapter the first reception of Joblot, the second and third will be discussed in chapters 5 and 8.

The year after the publication of Description des nouveaux microscopes, Joblot’s book was showered with praise by the Jesuit’s news Journal de Trévoux, the main bulwark of resistance that opposed, in particular, the Académie des sciences.²¹¹ Joblot had already published at least two articles in this journal on new mirrors he had invented.²¹² The 28 page review of his book was laudatory towards the author as much as towards the subject. The author reported the discovery of the “yet unknown animals”, highlighted the marvels of nature, quoting the “9000 species known by Tournefort”, each of which would give different animalcules when put in infusion. The utility of the microscope was displayed by the author in every manner: “Botanists will find out about the structure of the tissue, internal and external of plants”. He then listed above all the various professional uses of the microscopes proposed by Joblot, for painters, florists, writing experts, mineralogists, instrument makers, chemists, jewellers, apothecaries, oculists, glass-makers, physicians, anatomists, surgeons, watchmakers, antiquarians and engravers.²¹³ A whole utilitarian society was thus revealed through the microscope. But the most striking aspect was that the Jesuits followed point by point Joblot’s

antispontaneist experiments and theoretical consequences. The anonymous writer pointed out several observations taken from the book against spontaneous generation, and reported as well the hypothesis almost word for word.²¹⁴ It is not to be excluded that the author of the review could have been Joblot himself, but there is no enough evidence in to support this. However, in accepting Joblot’s inquiry, the Jesuits received a thesis that had been challenged and rejected by two famous fathers of their order, Athanasius Kircher (1602-1680) and Filippo Bonanni (1638-1725), the latter being a contemporary of Joblot. It does not appear that Joblot’s book was reviewed

elsewhere.²¹⁵ It is possible to explain this first weak reception by several factors, aside from the too easy appeal to the decline of microscopy. First Joblot was not a fellow of

211 Roger 1993, 181.

212 Joblot 1702; Joblot 1703.

213 An. 1719, 1406-1411. The list is inspired from that by Joblot 1718 I, in Avertissement.

214 An. 1719, 1421-1425.

215 I did not found evidence of other reviews, in Journal des savants and in the French journals published in Amsterdam at that time.

the Académie des sciences which seems a suitable milieu for the acknowledgment of his work. Elected professor of mathematics (geometry and perspective) in 1699, he was academician of the French Royal Academy of Sculpture and Painting in which he gave several microscopical talks. His colleagues were Coypel (1628-1707), Félibien (1619-1695), and other painters, engravers, and architects. If stimulated on aesthetic subjects, which sometimes appear in his book, such an intellectual environment obviously did not provide the suitable context to receive Joblot’s observations, even if the Academy proposed among its lectures naturalistic subjects, and also trained miniature painters.²¹⁶ Joblot equally demonstrated an interest in the microscope turned into a drawing

machine.²¹⁷ He actually does not seem to have used other official networks aside from own academy and the Jesuits. The latter rivalry with the Académie des sciences could possibly have made him enemies there. Indeed Joblot is quoted only once by Fontenelle in Histoire de l’académie, in the 1731 Eloge de Etienne-François Geoffroy, regarding the artificial magnets Joblot succeeded in making in 1701, and not his microscopical research.²¹⁸

Nevertheless Joblot also kept in touch with his circle of acquaintances, mostly the scholars of the old Académie (1666-1699) with whom he carried out several of his microscopical observations. Academicians of his own generation --in 1718 Joblot was 73 years old-- like Guillaume Amontons (1663-1705), Guillaume Homberg (1652-1715) and Jean Méry (1645-1721) are quoted as friends or collaborators. He also belonged to scientific circles, perhaps to the what was left of the Académie Bourdelot during the 1680s, and to the circle gathered around the Paris apothecary and French minister Mathieu François Geoffroy during the 1670s and 1680s.²¹⁹ There he met anatomists and physicians such as Joseph-Guichard Duverney (1648-1730), Homberg

216 If miniature painting was an obstacle to the microscopical iconography (Ruestow 1996, 68-77), however, eighteenth-century naturalists were best being engravers, like Lyonnet, or even miniature painter like Rösel von Rosenhoef.

217 Joblot 1718 I, 44-46.

218 Fontenelle 1733b, 93.

219 Fontenelle 1764, 93. On the Académie Bourdelot, the rival academy to the emergent Académie Royale des Sciences see Gabbey 1984.

and astronomers like Gian Domenico Cassini (1625-1712)and Sébastien,²²⁰ gaining the attention of the company by showing his magnets. Perhaps Joblot’s interest in

microscopes was also awakened by such discussions in circles. Microscopes were indeed a shared interest in this society, for Geoffroy and Homberg wrote respectively at the turn of the century a thesis on spermatic animalcules and papers on spiders observed thanks to the microscope.²²¹ Duverney corresponded with Malpighi, Pitcairne, Bidloo, Boerhaave, Ruysch, therefore with the most famous anatomists, microanatomists and physicians of the period 1660-1730. Having entered into the Académie des sciences in 1676, Duverney championed collection and anatomising, was greatly interested in insects,²²² and even conserved Swammerdam’s manuscript of Biblia naturae, which he wanted to publish, before he sold it to Boerhaave in 1727. Homberg, an MD educated by Guericke, Boyle and Graaf, was accustomed to building microscopes and other instruments, thus rising in the esteem of the academy.²²³ When in Rome, around 1685 he invented a tripod support for the microscope, that allowed focussing adjustement, quickly used by the instrument maker Campani.²²⁴ According to the Cartesian physicist Régis, Homberg had also written, prior to 1690, an unpublished treatise on spermatic animalcules.²²⁵

Through this range of scholars, and perhaps through other scholars interested in the microscope such as Father Nicholas Malebranche, Louis Carré (1663-1711), Philippe de la Hire (1640-1718) and Nicolas de Malézieu (1650-1727), the Royal Academy could follow Joblot’s works. La Hire for instance inserted, in his 1694 Traité des epicycloïdes, a leaflet from the instrument maker Michael Butterfield regarding the use

220 Fontenelle 1733b, 93.

221 Roger 1993, 310. See Homberg 1708, Geoffroy 1704.

222 Hahn 1971, 87; Lindeboom 1962, 153-154, letter from Boerhaave to Sherard of the 1st August 1727.

223 Roger 1993, 310; Salomon-Bayet 1978, 130. The source is Fontenelle (1741, 89) who states that Homberg in the 1680s and 1690s, built “..microscopes of his own, very simple, handy and precise, another source of phenomenon [than those caused by the air-pump he had built] (that) supplied him a place among the most important scholars”.

224 Bedini 1963, 399-400, 421.

225 Roger 1993, 87.

of the microscope, while Carré and Malézieu reported microscopical experiments and observations to the academy in 1707 and 1718. Certainly no work by Joblot could be published in the Mémoires de l’Académie des sciences,²²⁶ for, according to the racademic rules, only regular members were allowed to publish their texts in the Mémoires. But non-members of the inner circle could see their work reported by an academician, and hopefully abstracted by Fontenelle in the annual report Histoire de l’Académie.

The scientific culture of the early eighteenth-century Paris Académie des sciences was characterised by some axes such as the utility of the research programme, that gave priority to technological and economical questions, as well as to the unveiling of professional secrets.²²⁷ Christian Licoppe has highlighted the rupture in the practices of reproducibility for physical and technical evidence in the new Académy.²²⁸ On the other hand, “Life sciences”, human, animal anatomy and physiology were also the focus of the academy, with anatomists such as Méry, Duverney, Homberg, Littre and Dionis, a trend analysed by Roger and Salomon-Bayet.²²⁹ But another research programme has yet been ignored by historians. The germ theory to which Joblot’s experimental system related, was, at least for the Académie Royale des Sciences, the accepted system, defended as such by many scholars since the rebirth of the academy in 1700. During the first forty years of the century the importance of the germ theory was well settled for animal and vegetable kingdoms, supported by the main anatomists, botanists, and most of all, by the secretary Fontenelle (1657-1757).²³⁰ The ex ovo omnia was conceived as a programme, and was furthermore established with the victory of the anatomist Alexis Littre (1658-1725) over Jean Méry on the existence of the egg in humans in 1702. Concerning animals and humans, the period 1700-1745 saw the

226 Hahn 1971, 19-20.

227 Licoppe 1996, 116-24, Briggs 1991,. On the procedure of the patent in France see Hahn 1971, 66-67.

228 Licoppe 1996, 88-89ff.

229 Roger 1993, 250; Salomon-Bayet 1978, 123ff.

230 Most of the works on germ theory were favourably commented by Fontenelle (1704, 52; 1708a, 9; 1708b, 49-50, 1714b, 41-42).

establishment of the doctrine of the germ against animalculism.²³¹ So general was the claim that the botanist Joseph Pitton de Tournefort (1656-1708) did not hesitate in identifying germs in the mineral kingdom as the regular method of reproduction! How indeed to account for the “corne d’ammon”, a fossil shaped as a volute?²³² He stated, in 1702, that the “germ of the stones and of the metals is a sort of powder that comes perhaps out of stones and metals during the time they still are alive, which is to say that they grow (..). One can compare the dust we call the germs of the stones to the seeds of several plants; the seeds of the ferns, of the maidenhair fern, of the mosses, of the truffles and similar plants can only be discovered with the microscope”.²³³ The early years of the century saw the botanist Charles Plumier (1646-1706) publishing the description of the seeds of the American fern, while Antonio Vallisneri (1661-1730) in Padua discovered the seeds of the Lenticula palustris.²³⁴ Nevertheless, the prestige of the famous botanist --Tournefort was director of the King’s Jardin des plantes-- was probably sufficiently important to suppress criticisms towards the “vegetating stones”.

But after Tournefort’s death in 1708, research on the seeds of the stones was quickly contested. In Eloge de Tournefort, Fontenelle excused the man who “transformed everything into what he liked the most”,²³⁵ hence taking minerals for plants. Already in 1709, Réaumur, then a young man of 26, took the example of the formation of shells, aquatic and terrestrial, to indirectly confirm that no germs were present. Instead through both simple vision and a microscope, he detected an infinite number of small ducts in the shell,²³⁶ showing its growth to be made by “intussusception”, by adding small particles to each hole of the “riddle”. Physicians and botanists such as Claude-Joseph Geoffroy (1685-1752), the brother of the chemist who had built the chemical tables of affinity, and Sébastien Vaillant (1669-1722) fed the criticisms, and Réaumur questioned

231 Roger 1993, 364-384.

232 Tournefort 1704, 223. In his works arguing for a distinction between two kinds of formation, crystallisation for stones and “organic mechanism” for plants and animals, Bourguet (1729, XI, 78-80) noticed that the germs of Tournefort had soon vanished.

233 Tournefort 1704, 233.

234 Plumier 1705, 2-3, 123, 143, see plates 2, 18, 19, 25, 142. Vallisneri 1704, 250-251.

235 Fontenelle OD, 1731, 4, 160.

236 Réaumur 1711, 370.

Tournefort’s idea even more seriously when carrying out experiments on the formation of the stones in 1721.²³⁷ But the other part of the research programme on the seeds of cryptogam promoted by Tournefort already in 1692²³⁸ --following the impulse of the Italian scholars-- met with many echoes in the Academy and fitted well into the general scheme of ovism, debated by nearly everyone in Europe at the same time. In the

Academy, Fontenelle had strengthened the research of the germs through its link to the microscope: “perhaps we ask where are the seeds of the stones, but would we have ever discovered these of the mushrooms and of the fern without the microscope?”.²³⁹

Tournefort himself was enough of a microscopist to show in 1705, after Hooke, that

“still the moldiness is a dangerous illness (...) the microscope shows that the mold is but a flower bed”.²⁴⁰

Contrary to the claim by the historians of microscopy that the “triumph” of the preformationist theory “depended less on the quality of observational evidence for it, which was ambiguous and fragmentary, than on metaphysical considerations about order and agency”,²⁴¹ many authors followed Tournefort’s empirical research

programme by applying the research of the seeds and of other germs to many orders of cryptogam. Plumier, a disciple of Tournefort, had displayed his discovery of the seeds of fern in 1705. Between 1711 and 1713, in the Academy, five papers were consecrated to microscopical research carried out after Tournefort’s death by three scholars, C.-J.

Geoffroy, Jean Marchant (1650-1738), and Réaumur (1683-1757) on the seeds of the truffles, mushrooms, maple-tree, fucus, and lichen.²⁴² In 1711 Réaumur assessed the state of the research and remarked that many seeds, especially from fungi and lichen

237 Réaumur 1723, 258.

238 In a paper read before the Academy at the end of May 1692, concerning an “extraordinary mushroom”, Tournefort discussed previous discoveries of the seeds of plants carried out since the invention of the microscope, in vegetables such as Polypodes, Ophioglossum, Orchis, Elleborine, Orobranche, Ophris and Pryole. From all this he deduced that mushrooms should also have seeds and launched the programme. See Tournefort 1730, 121-124.

239 Fontenelle 1704, 52.

240 Tournefort 1706, 336.

241 Wilson 1995, 103.

242 Geoffroy 1714, 26-31; Marchant 1714, 103-105; Réaumur 1714b, 293-294; Réaumur 1714c, 32-34; Marchant 1716, 233.

were still unknown.²⁴³ The same year, he discovered the seeds of fucus, while Marchant was working on the generation of the lichen. Réaumur’s botanical activity did not stop there. In 1722 he thought, but with some doubts, that he had discovered the seed of nostoc^g.²⁴⁴ From 1728 on a new actor was on the scene, Henri-Louis Duhamel du Monceau (1700-1782), with a study of the seeds of cryptogam such as truffles in

1728.²⁴⁵ He also applied the programme to the identification of the causes of the plant’s illnesses and to their multiplication through grafting. In particular, an outcome of Tournefort’s programme was the demand in 1728 by Bernard de Jussieu (1686-1758) to establish a separate class for the fungi. During the same period, Jussieu also observed seeds of fungi and lichens, while Réaumur identified marks in stones and plaster to be lichen.²⁴⁶ Pre-existence and transmission of the species through the germ was thus designated as a research programme involving the work of many scholars of the Academy. Vegetable and animal germs were conceived as two facets manifesting the same process, and ex ovo omnia a programme that Fontenelle put into general use in 1707 when he reported on a paper by Tournefort on the generation of mushrooms: “If to this speculation on the invisible germs we add that of the invisible eggs of the insects, which must be quite similar, the earth will be filled with an inconceivably endless number of vegetables and animals already completely formed and shaped in miniature, which only wait to appear in large through some favourable accident”.²⁴⁷ Along with botany, the microscope was applied to germs other than those of animals. Are not “The seeds of plants and the eggs of the animals (...) the same thing under different names”?

wrote Fontenelle, already in 1702.²⁴⁸

Most of these works required microscopes and lenses as routine tools of investigation.

Though advertisement seems to have been avoided, these studies were undertaken

243 Réaumur 1714b, 282.

244 Réaumur 1724, 124-125.

245 Duhamel 1730a, 107.

246 Duhamel 1730a, 107; Duhamel 1730b; Jussieu 1730, 379; Réaumur 1731, 188.

247 Fontenelle 1708b, 49-50.

248 Fontenelle 1704, 52.

within the framework of a research programme --germ theory-- and allowed the start or the establishment of new naturalistic fields of research. Notably the studies on

regeneration already begun by Claude Perrault (1613-1688), and carried on by Réaumur in 1712, on hermaphroditism by La Hire, Amontons, C.-J. Geoffroy, Méry, Réaumur, on parasitism by Tournefort, Réaumur, Geoffroy, Duhamel, Deslandes, were all microscopical subjects launched in the seventeenth-century and to which the French academicians sometimes brought significant contributions; all this prepared for the 1740s boom in natural experimental research. These research programmes presupposed interaction of an important number of scholars who employed the microscope, and were able to bring criticisms to the meetings of the Académie. We can measure the

importance of the Paris academic community in comparison to the Royal Society during the same period. After 1700, in London there are few scholars still using the

microscope. In the Royal Society, Leeuwenhoek himself supplied more than half of the papers in the Philosophical Transactions.²⁴⁹ But Leeuwenhoek became unreachable and isolated after 1703 because of the lack of scholars able to repeat and consequently understand his observations. The anonymous C.H. in 1703 claimed Leeuwenhoek to be a reliable observer and repeated some of his observations with a Wilson microscope, while the same year the anonymous C. was one of the last British scholars to discuss Leeuwenhoek’s observation, actually to enter into a controversy of priority with him.²⁵⁰ Two letters from Leeuwenhoek to James Jurin were eventually published in the

Philosophical Transactions in 1723, on the diameter of blood globules.²⁵¹ Contrary to this situation, the French school community represented a critical mass, that is

sufficient scholars to launch and keep a dynamic of the production of knowledge that filled the different branches of the experimental natural history programme. The

following table A clearly shows, by comparison with the Royal Society, that the critical mass existed in France.

249 See Fournier 1991, 17.

250 C.H. 1703, 1358; C. 1703, 1494.

251 Leeuwenhoek 1723a, Leeuwenhoek 1723b. See Rusnock 1996, 121-122.

Table A. Frequency of microscopical papers per author in PT and M.AdS 1700-1730²⁵²

The number of authors who published papers is similar in both academies, though there are more papers in the PT. There are 35 authors of 95 papers in M.AdS and 36 authors of 110 papers in PT. But the important difference relates to the integration of the works done within a scientific community. Of the 110 papers, Leeuwenhoek signed more than half (66). This clearly shows that the critical mass was attained in the Paris Academy, with two aspects: 1. there are 16 scholars writing more than one paper, and 2. there is no real gap between the leader (Réaumur) and the base, but a relatively good continuity.

The situation is exactly inverted in the Royal Society. The base is weak, while the summit is too strong, and there is a huge discontinuity between Leeuwenhoek and the base. Moreover Leeuwenhoek did not live in London, which greatly restricted his participation in the social dynamics of the Society; contrary to what happened in Paris.

The situation is exactly inverted in the Royal Society. The base is weak, while the summit is too strong, and there is a huge discontinuity between Leeuwenhoek and the base. Moreover Leeuwenhoek did not live in London, which greatly restricted his participation in the social dynamics of the Society; contrary to what happened in Paris.