HISTORY OF BIOLOGY 1700-1799

The time of Enlightment

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1700 Joseph Pitton de Tournefort (Aix-en-Provence, 1656 - Paris, 1708) publishes his Institutiones Rei Herbariæ where he develops the first generic classification of plants by separating cleraly between genus and species.

~1700 Friedrich Hoffman (Halle, 1660-1742) teaches that life is a purely mechanical process, from whose functions the activities of the soul can be excluded. The heart causes blood to move, and a "spiritus animalis" circulates in the the nervous fibres.

1702 Antony van Leeuwenhoek gives the description of many protists, among which those we now name ciliates.

1703-1705 Robert Hooke, who had made extensive use of the microscope and discovered the first cell-like structures in plants, had speculated in his Lectures and Discourses of Earthquakes and Subterraneous eruptions on the geological mechanisms responsible for the distribution of fossils. This reflection is published posthumously.

1704 Antonio Maria Valsalva (Imola 1666 - Bologna 1723), an Italian anatomist who had discovered the principle of improving effort by control of air pressure (Valsalva maneuver), publishes De Aure humana ("On the Human Ear").

1705 Antonio Pacchioni (Reggio nell'Emilia 1666 - Roma 1726) in his Dissertatio epistolaris de glandulis conglobatis durae meningis humanae, indeque ortis lymphaticis ad piam meningem productis describes arachnoid granulations that are special one-way cerebrospinal fluid valves.

1707 Isaac Newton (Woolsthorpe Manor 1642- London 1727), publishes his Arithmetica Universalis.

1708 John Marten (1673 - 1737), surgeon and physician, publishes a book on the causes and treatments of venereal diseases A treatise of all the degrees and symptoms of the venereal disease, in both sexes; Explicating Naturally and Mechanically, its Causes, Kinds, various Ways of Infecting; The Nature of Hereditary infection; Certainty of knowing whether Infected or not; Infallible way to prevent Infection; Easiness of Cure when infected; Reasons why so many miss of Cure; How to know when, and when not, in Skilful Hands for Cure, and the Use and Abuse of Mercury in the Cure. Necessary to be Read and Observ'd by All Persons that Ever had, (many other Diseases being occasion'd by the Venereal Taint and Mercury) Now have, or at any time May have, the Misfortune of that Distemper, in order to prevent their being Ruin'd by Ignorant Pretenders, Quacks, Mountebanks, Impostors, &c. whose Notorious Practices are clearly evinc'd. To which is added, The Cause and Cure of Old Gleets and Weaknesses in Men and Women, whether Venereal or Seminal, briefly describing the Use and Abuse of their Genital Parts, and why Gleets (as sometimes they do) hinder Procreation, causing Impotency, &c. in Men, and Barrenness, Miscarriages, &c. in Women. With some remarkable Cases of that kind incerted. The whole Interspers'd With peculiar Prescriptions, many pertinent Observations, Histories, and Letters of very extraordinary cures. The like, for general Advantage, never Publish'd by any Author, Ancient or Modern, since the Disease came first to be known in the World.

1709 Hermann Boerhaave (Vorherr 1668 - Leyden 1738) in his Aphorismi de Cognoscendis et Curandis Morbis states that "the power to exert movement is called function, which takes place in accordance with mechanical laws and only by them can be explained."

1709 Francis Hauksbee (1666 - 1713) makes the first accurate observations of capillary action in glass tubes.

1710-1713 Posthumous publication of John Ray's (1628-1705) Historia Insectorum and Synopsis Methodica Avium & Piscium.

1714 Daniel Gabriel Fahrenheit (1686-1736) invents a mercury thermometer with a temperature scale. Following the Danish astronomer Ole Romer, who had needed to define a temperature scale to establish his observations on the speed of light, he established a temperature scale by choosing for zero not the temperature of the melting ice but a mixture salt comprising ammonium chloride. Under these conditions the water / ice mixture temperature is 32°, and the human body temperature is 96°. Water boils at 212 °.

1714 Dominique Anel (Toulouse, France 1679 - 1730) invents the first fine-point surgical syringe.

1714 Gottfried Wilhelm von Leibniz (Leipzig 1646 - Hanover 1716), in La Monadologie (written in French) states that the universe's ultimate constituents are monades, simple substances, each of which perceives the universe from a different point of view. Their perceptions are harmonius, and what is needed is a mathematics which will demonstrate the universality of the relations between these points of view. Read his text of 1675: Drôle de Pensée, touchant une nouvelle sorte de représentations (about popularisation of science).

1714 Emanuel Timoni (Constatinople ~1670 - 1718) describes the practice of variolation for the Royal Society.

1715 Georg Ernst Stahl (Ansbach 1660 - Berlin 1734) publishes his Opusculum Chymico-Physico-Medicum. Beginning as an alchemist, he postulated the existence of a fluid substance, phlogiston (see Presocratics), in both combustible substances and metals. This accounted for the many processes in inorganic nature. His medical theory, similar to Anaxagora's was exposed in his Theoria medica vera, where "mixtio" between different substances of the body play a major role. Texture and structure make the body: "living body is nothing else than that which has structure".

1715 Vieussens describes the structure of the heart's left ventricle, with the path of coronary arteries. He also describes several pathological conditions of the heart in his Traité nouveau de la structure et des causes du mouvement naturel du cœur.

1715 Death of Louis the XIV^th (Paris 1643 - Versailles 1715). Thomas Fairchild (1667-1729) announced the production of the first artificial hybrid plant and published The city gardener in 1722.

1716 Jean-Baptiste Goiffon (1657-1730), physician in Lyons, proposes that contagious diseases such as plague, variola, leprosy, rabies or scale are due to the action of animalcules (Relations et dissertation sur la peste du Gevaudan). He also constitutes a detailed botanic analysis of the region.

1717 Antony van Leeuwenhoek describes nerve fibers in cross section.

1718 Abraham de Moivre (Vitry 1667 - London 1754), in The Doctrine of Chances: or, A method of calculating the probabilities of events in play, states that chance can neither be defined nor understood, but probabilities can be calculated.

1718  Louis Joblot (Bar le Duc 1645 - Paris 1723), fascinated by a previous visit of Huygens develops the contruction of microscopes and studies a variety of insects and microscopic animals: he publishes his observations in Descriptions et usages de plusieurs nouveaux microscopes, tant simples que composez; Avec de nouvelles observations faites sur une multitude innombrable d'insectes, & d'autres animaux de diverses especes, qui naissent dans des liqueurs préparées, & dans celles qui ne le sont point, with important discussions about the question of spontaneous generation. After his death another edition was published: Observations d'histoire naturelle faites avec le microscope, sur un grand nombre d'Insectes, & sur les Animalcules qui se trouvent dans les liqueurs préparées, & dans celles qui ne le sont pas, & avec la description et les Usages des différents microscopes. He clearly observes what we now name Protozoa.

1719 Valsalva announces the presence of an excretory duct from the adrenal communicating with the left epididymis.

1720 Benjamin Marten (1704-1784) proposes that consumption (phthisis) is due to animalcules, reviving the contagium vivum hypothesis.

1721 Zabdiel Boylston (Brookline 1676 - 1766) variolates patients in the region of Boston. A few die from infection, but much less than from smallpox.

1721 Antonio Vallisneri (1661-1730) in parallel with his studies in medicine, in De’ Corpi marini, che su’ Monti si trovano; della loro Origine; e dello stato del Mondo avanti ‘l Diluvio, nel Diluvio, e dopo il Diluvio describes in Italian in great details fossil species uncovered in his country's soil.

1722 Having been disfigured by small pox, Lady Mary Wortley Montagu who observed "variolation" in Constantinople in 1718 introduces the practice of smallpox inoculation in England despite much reluctance.

1727 Foundation of the seed-breeding establishment Vilmorin-Andrieux et Cie. This company further develops and spreads sugar beet cultivation for sugar production during the Napoleon era. Many systematic books in botany were sponsored by the Vilmorin's until very recently.

1727 That same year, the philanthropist priest Stephen Hales (Beckesbury 1671-Teddington 1761) publishes Vegetable staticks, or an account of some statical experiments on the sap in vegetables: being an essay towards a natural history of vegetation where he observes that plants are nourished in part by the atmosphere. He also studies the ascent of water in plants and applied physical principles to the study of plant physiology. For this he applies quantitative methods (in particular weighting).

1730 René Antoine Ferchault de Réaumur (1683-1757) invents the alcohol eighty degrees thermometer scale. Réaumur was to develop observations in many domains of biology. One of his important findings (later emphasized by Thomas Henry Huxley) was the discovery of a family which had a child with an excessive number of fingers and toes, which phenomenon was afterwards inherited by its descendants. Réaumur coined the word automatisme to characterize movements of living organisms which exist independently of will.

1733 Hales makes the first measurement of blood pressure (Haemastaticks).

1734-1740 David Hume (1711 - Edinburgh, 1776), in A Treatise on Human Nature, describes the mind as a bundle of perceptions, causal relation as the conjunction of two events, and and apparent sequence of events as, in fact, a sequence of perceptions. Thus the connections which science establishes are "entirely arbitrary," and the "utmost effort of human reason is to reduce the principles, productive of natural phenomena, to a greater simplicity".

1735 Carl, son of Nils Ingemarsson, taking the name of Linnaeus (ennobled as Carl von Linné (Sunnerbo 1707- Uppsala 1778)) publishes his first edition of Systema Naturae, in which, using classifications introduced by Aristotle and Porphyrus (Porphyrus' tree), he introduces many of the concepts and conventions that are still used by taxonomists today.

1736 Jean Astruc (Sauve 1684 - 1766) (who in 1753 recognized that the first book of the Bible was from two different hands) coins in his book Tractatus therapeuticus et pathologicus the term reflex to represent an automatic movement after the analogy of the reflection of a light beam by a mirror.

1736 The botanist Henri-Louis Duhamel du Monceau (Paris, 1700 - 1782) proves that the element later identified as potassium differs from sodium.

1738 Jan Swammerdam's (Amsterdam 1637 - 1680) book De Bijbel der Natuure, of Historie der insecten, a dutch translation of a book published in 1583 by Philippe de Mornay, sieur du Plessis Marly De la vérité de la religion chrestienne. Contre les athées, epicuriens, paiens, juifs, mahumedistes, & autres infideles is published posthumously by Boerhaave of Leyden. His description the development of insects and invertebrae as well as of the cleavage in the frog's egg has an enormous impact on the theory of preformation. This work, meant to use Nature against any temptation of atheism, established firmly that the progeny should resemble its parents, going against former beliefs that women influenced by the view of monsters could give birth to monsters.

1738  Daniel Bernoulli (Groningue 1700 - Bâle 1782) publishes the first theory of hydrodynamic, Hydrodynamica, sive De viribus et motibus fluidorum commentarii, where he discovers a way to measure blood pressure.

1739 Publication of Medicina rationalis systematicae by Friedrich Hoffman.

1740 Astruc publishes his famous book on venereal diseases: Le médecin de soi-même, ou méthode simple et aisée pour guérir les maladies vénériennes. Avec la recette d'un chocolat aphrodisiaque, aussi utile qu'agréable. Nouvelle édition, augmentée des analyses raisonnées & instructive de tours les ouvrages qui ont paru sur le mal vénérien depuis 1740 jusqu'à présent, pour servir de suivre à la bibliographie de m. Astruc; et de la traduction française de la dissertation de m. boehm. The title of this book will be much plagiarized, cf in 1843 John Vaughen in the USA The medical guide, or, Every man his own physician : in which is contained a lucid and thorough examination of the venereal disease in all its features, with simple and effectual modes of treatment which all may understand and practise, without the aid of a physician.

1740 Anton Lazzaro Moro (1687 - 1764) proposes that mountain uplift is due to lava eruptions and that this explains why marine fossil remains may be found on the top of mountains (De' crostacei e degli altri marini corpi che si trovano sui monti).

1740 - 1741 Emanuel Swedenborg (Uppsala 1688-London 1772) publishes his famous treaty of anatomy where he places all animal properties as demending on their brain: Oeconomia regni animalis.

1741 Pierre-Louis Moreau de Maupertuis (Saint Malo 1698 - Basel 1759) In his Essai de cosmologie, suggests the idea later popularized by Spencer of "survival of the fittest".

1742 Publication of the first volume of the Praelecionets academicae in proprias Institutiones rei medicae by Hermann Boerhaave.

1742 Charles Marie de Lacondamine establishes the Celsius temperature scale, named after Anders Celsius (Uppsala 1701 - 1744).

1744 George Berkeley (Dysert Castle 1685 - Oxford 1753) in his text Siris: a chain of philosophical reflexions and inquiries concerning the virtues of tar water: and divers other subjects connected together and arising one from another, presents tar-water, made by stirring together tar and cold water, and drawing off the impregnated water after the solid residues have settled as a universal remedy.

1744 François Chicoyneau (Montpellier 1672 -1752) and Jean-Baptiste Sénac (1693 - 1770) publish a Traité des causes, des accidens et de la cure de la peste, avec un recueil d'observations et un détail circonstancié des précautions qu'on a prises pour subvenir aux besoins des peuples affligés de cette maladie, ou pour la prévenir dans les lieux qui en sont menacés, on the epidemic of plague in Marseilles.

1744 Abraham Trembley's (1710-1784) Mémoires pour servir à l'histoire d'un genre de polypes d'eau douce à bras en forme de cornes shows that the hydra is not a plant (as van Leeuwenhoek had believed) since the tentacles could grab objects and bring them to a primitive stomach. he ability of the hydra, a polyp, when cut into pieces, to grow a fresh organism from each fragment.

1745 Following his compatriot Trembley, Charles Bonnet (Geneva 1720 - 1793) demonstrates the regenerative ability of annelid worms.

1745 Maupertuis publishes anonymously his Vénus Physique, where he ridicules people interpreting birth marks as signs of God or as signs of devils of objects seen by pregnant mothers. In his Vénus Physique, criticizing Swammerdam, Maupertuis proposes the theory that molecules from all parts of the body are gathered into the gonads and speculated on the causes of evolution, homeomeres (later called "pangenesis"). He also criticizes preformationism while advancing his own refined form of epigenesis.

1745 Johann Nathanael Lieberkühn (Berlin 1711 - 1756) in his Dissertatio anatomico-physiologica de fabrica et actione villorum intestinorum tenuium hominis describes for the first time the intestine epithelium crypts, known today to harbour the intestine stem cells.

1746 Étienne Bonnot de Condillac (Grenoble 1715 - Flux 1780), in his Essai sur l'origine des connaissances humaines: Ouvrage où l'on réduit à un seul principe tout ce qui concerne l'entendement humain, studies the relation between sense-perception and consciousness and developed the theory that all knowledge comes from the senses and that there are no innate ideas.

1746 Bonnet discovers natural parthenogenesis in the aphid. He also studies photosynthesis, phototropism and growth movements (phyllotaxis) in plants.

1747 Albrecht von Haller (Berne 1707- 1777) gives a general foundation for physiology in his book Primae lineae physiologiae in usum praelectionum academicarum.

1748 John Turberville Needham (London 1713 - Brussels 1781) writes a letter to Martin Folkes, president of the Royal Society: Observations upon the Generation, Composition, and Decomposition of Animal and Vegetable Substances, where he "demonstrates" the spontaneous generation of life.

1748 Leonhard Euler (Bâle 1707 - St Petersburg 1783) publishes Introductio in Analysin Infinitorum, on analytical geometry.

1748 Julien Offroy de la Mettrie (Saint Malo 1709 - Berlin 1751) publishes L'Homme machine where he discusses the localization of mental functions in mechanistic terms. Taking ground on views similar to those of Empedocles of the origin of animals he states that human beings were first composed by trial and errors of spare parts combining randomly. Some were ready to live, and being brought up by wild animals became the humans we know. Living particles fill the universe (homeomers).

1748 John Fothergill (1712 - London 1780) first describes diphtheria in his book: An account of the sore throat attended with ulcers: a disease which hath of late years appeared in this city, and in several parts of the nation.

1749 Sénac publishes the first general treatise of cardiology: Traité de la structure du cœur, de son action et de ses maladies.

1749-1777 Georges-Louis Leclerc de Buffon (Montbard 1707 - Paris 1788), author of a major Histoire Naturelle, regards spermatozoa as "molecules organiques vivantes" which multiply in the semen. He explicitely refutes the preformationist theory of Charles Bonnet, preferring to speak of a "moule intérieur" as driving construction of the adult organism. Buffon's Histoire Naturelle asserted that species were mutable and drew attention to vestigial organs. There was not trace of transformism, however, in his view of Nature. However, fossils suggested to him that the Earth was much older than what was then assumed.

1751 In Maupertuis' evolutionary work Systême de la nature, Essai sur la formation des corps organisés, the author develops theoretical speculations on the nature of biparental heredity based on his study of the occurrences of extra fingers (polydactyly) in several generations of a Berlin family. He demonstrates that polydactyly could be transmitted by either the male or female parent, and he explains the trait as the result of a change in the "hereditary particles" possessed by them. He also calculates the mathematical probability of the trait's future occurrence in new members of the family.

1751 Charles Marie de la Condamine (1701 - 1774), member of the French Académie Royale des Sciences decides to measure the shape of the Earth at the equator to distinguish between the Cartesian view (that the Earth was elongated at the poles) and Newton's (that the Earth was thickened at the equator). He leaves Paris to reach Quito in 1736 for an expedition that was to last much longer than expected, returning after following the course of the Amazon, first to Cayenne in 1744, and then back to Paris in 1745. The summary of his travel Journal du voyage fait par ordre du roi, a l'Équateur, servant d'introduction historique a la Mesure des trois premiers degrés du Méridien, reports numerous observations from the Natural Sciences, highlighting in particular the curative effect of cinchona against malaria fever.

1751 Mikhail Vassilievitch Lomonossov Михаил Васильевич Ломоносов (Kholmogory 1711 - 1765) pronounces a discourse for the Science Academy of Saint Petersburg, Слово о пользе химии Slovo o pol’ze khimii [Discourse on the utility of chemistry] against the theory of the phlogiston. Ten years earlier, in his Элементы математической химии Elementy matematiceskoj khimii [Elements of Mathematical Chemistry] he had proposed a theory of chemistry highly ahead of his time.

1751 Linné publishes his Philosophia botanica. He states that the difficulty he finds in making classes of plants is witnessing the infinite variety of living organisms. This should be borne in mind today by scientists trying to find universal causes for every new form of life: invariants are in the form of relationships (information) and in the underlying chemistry (matter and energy).

1751 Théophile de Bordeu (1722-1776) publishes his Recherches anatomiques sur la position des glandes et sur leur action, where he maintains that the lymphatic glands as well as the nervous system have vital activity, and secretions drain the vital essences that resided in every part of the body. He will also publish his Recherches sur les maladies chroniques: leurs rapports avec les maladies aiguës, leurs périodes, leur nature & sur la manière dont on les traite aux eaux minérales de Barèges & des autres sources de l'Aquitaine.

1752 Following Swammerdam, Réaumur writes a Mémoire pour servir à l'histoire des insectes. He shows by experiments the effect of gastric juice in digestion. Obtaining gastric juice from a chicken by letting the bird swallow a sponge attached to a piece of thread with which the sponge was later recovered from the stomach he uses it to act upon various substancesand shows that it liquefies meat.

1753 James Lind (1716 - 1794) in A Treatise of the Scurvy: in three parts, containing an inquiry into the nature, causes, and cure, of that disease : together with a critical and chronological view of what has been published on the subject (translated into French as Traité du Scorbut) calls attention to the value of fresh fruits in preventing scurvy. Yet, the lengthy discussion on the causes of the disease will result in that the Admiralty is not convinced, and it will take forty years before anyone used the lemon juice.

~1753 Gabriel-François Venel (1723 - 1775) writes the entry Chimie in Diderot-d'Alembert Encyclopédie. In this entry he emphasizes the complementarity principles that rule chemistry in terms of complementary shapes, predating many views still active in biochemistry (lock and key). He also writes an interesting entry on Végétation métallique, where he compares biological and mineral structures, an analogy which is still plaguing the thought of naïve scientists in the present days, but is also at the basis of very important discoveries in the domain of shapes, fractals in particular.

1754 Condillac's Traité des sensations builds on his previous work where he claims that every type of knowlege has to come through the sense organs.

1754 Bonnet notes the emission of bubbles by a submerged illuminated leaf. In his Recherches sur l'Usage des Feuilles dans les Plantes mentions the different phyllotactic arrangements of leaves, the genetic spiral, and one family of parastichies.

1754 Samuel Klingenstierna (1698 - Uppsala 1765) succeeds in demonstrating that the problem of making microscope achromatic lenses (which was declared insoluble by Newton) could be solved. For this discovery he was awarded a prestigious prize from the Academy of Science in St. Petersburg in 1762. Under his instruction, John Dollond (1706-1761) makes the first achromatic lenses, but they could not be used for microscopy before Chevalier and Amici constructed them during the following century.

1756 Joseph Black (Bordeaux 1728 - Edinburgh 1799) publishes his (re) discovery of "fixed air", now known as carbon dioxide (Experiments upon Magnesia Alba, Quick-Lime, and some other Alkaline Substances).

1758 In Sur la formation du coeur dans le poulet, sur l'oeil, sur la structure du jaune &c. premier mémoire: exposé des faits., von Haller describes the chick's embryo development.

1758 The jesuit Rudjer Josip Boskovic (Ragusa 1711 - Milano 1787) proposes that atoms are made of particles with alternating repulsive and attractive envelopes.

1758 Jean-Jacques Rousseau (1712-1778) publishes his Lettre à d'Alembert sur les spectacles, where he discusses the role of theater to convey the importance of rational thought (against religious fanaticism, in particular).

1759 Guillaume François Rouelle (Rouelle l'Aîné) (Mathieu 1703 - Paris 1770) apothecary, publishes his Cours d'expériences chymiques, where he introduces quantitative measurements in chemistry. Lavoisier was one of the followers of his lessons. Rouelle separates salts according to their acidic or neutral composition and clarifies a much debated domain of chemistry. His course splits chemistry into three parts: the vegetal domain (including wine and vinegar), the animal domain (including milk and urine) and the mineral domain (coal, sulphur, lead, tin, iron, copper, gold...). His work explicitly states that salts are compounds, and that one should experimentally show by separation first, that primary elements are present, while synthesis should, from the elements allow formation of the predicted compound (for example in cinnabar, made of sulphur and mercury).

1759 Caspar Friedrich Wolff (Berlin 1733- St Petersburg 1794)'s Theoria Generationis (In Latin, with citations in German and French) proposed an epigenetic (he uses the word evolutio; ^{unfortunately in the WWW copy of the book the page containing the first occurrence of this word is missing}) theory of development which was opposed to preformationism and laid the basis for modern embryology. Wolff applied the microscope to the study of animal embryology and remarked that Partes constituae ex quibus omnes corporis animalis partes in primis initiis componuntur, sunt globuli, mediocri microscopio cedentes semper "the particles which constitute all animal organs in their earliest inception are little globules, which may be distinguished under a microscope."

1760 John Hunter (Long Calderwood 1728- London 1793) develops an insightful comparative approach to anatomy, and establishes a museum of natural history at his home.

1760-1790 According to Charles Darwin (Chapter 1 of On the Origin of Species...), British livestock breeds are improved by a thirty-year program of selection and inbreeding undertaken by Bakewell, the Colling brothers, Bates, and others.

1761 Leopold Auenbrugger (Elder von Auenbrugg) (Graz 1722 - Vienna 1807), an hotel-keeper's son, applies percussion of the chest (from his fathers's experience he knew that a full wine cask makes a different sound when tapped than an empty one) as a diagnostic method. He used this technique to evaluate cavities produces by phtisia (tuberculosis). His Inventum Novum ("A New Discovery that Enables the Physician from the Percussion of the Human Thorax to Detect the Diseases Hidden Within the Chest") had little impact until translated into French by Corvisart (Essai sur les maladies et les lésions organiques du coeur et des gros vaisseaux.Traduction de l'essai d'Auenbrugger avec commentaires:  Nouvelle méthode pour reconnaître les maladies internes de la poitrine par la percussion de cette cavité)

1761 Giovanni Battista Morgagni (Forli 1682 - Bologna 1771) publishes a book De Sedibus et Causis Morborum per Anatomen Indagatis (The Seats and Causes of Diseases Investigated by Anatomy), which recommended studying body's organs rather than its parts, and proposes that the symptoms of disease result from pathological changes in the organs.

1761-1766 Joseph Gottlieb Köhlreuter (Sulz 1733 - Karlsruhe 1806) makes experiments of artificial pollinisation (he discovers the role of insects in this process) and publishes reports describing 136 experiments in artificial hybridization. His discovery of quantitative inheritance foreshadows the work of Mendel.

1762 Marcus Antonius Plenciz (1705 - 1786), in Opera Medico-Physica, formulates the view that infectious diseases are caused by a living innumerable animalcules (invisibilia animalcula) propagated by air or contact and each of a type specific of each disease: Quaestio prima: quare a variolis, variolae; a morbillis morbilli; as scarlatina pariter scarlatina; item a peste pestis; a lue venerea lues venerea; idem discendum est de hydrophobia, scabie, aliisque morbis contagiosis, ordinaria naturae lege oriantur? Unde fignum evidentissimum est, ut dein clarius patebit, hos & similes morbos specie inter se differe.[...] igitur dicendum est, quod, sicut plantas, & eorum semina specie differe palam fatemur, quia ordinaria naturae lege a certo semine certaim tantum plantam exoriri observamus, idem pariter dicendum sit de morbis contagiosis; nimirum ispsos, eorumque causas specie inter se differe. He aso states that these germs preexist (with a view typically creationist, and opposed to spontaneous generation): Si itaque nullum in rerum natura semen producitur de novo, debet necessario admitti, omnia haec a principio mundi creata fuisse, nunc vero unum ex altero evolvi.

1763 Michel Adanson (1727-1806) in Familles Naturelles des Plantes gives the first botanical description of the tree and advocates an empirical approach to taxonomy based on shared characters rather than evolutionary relationships.

1763 Edward Stone (Chipping Norton 1702 – 1768) proposes the bark of the willow - containing salicylic acid - as a medicine; it later becomes the basic ingredient of aspirin.

1764 Angelo Gatti (Ronta 1724 - Pisa 1798) publishes in Brussels his Réflexions sur les prejugés qui s’opposent aux progrès et à la perfection de l’inoculation (Reflexions on Variolation) in which he describes its benefits and the nature of smallpox infection.

1764 Domenico Cotugno (Ruvo 1736 - Napoli 1822) after having identified the canal of the inner ear, describes spinal subarachnoid cerebrospinal fluid (De ischiade nervosa commentarius).

1764 Köhlreuter introduces artificial fertilization for the management of tobacco plants.

1764-1774 Bonnet, developing his "incapsulation" theory of parthenogenesis, in his Contemplation de la Nature champions the preformation doctrine.

1765 Lazzaro Spallanzani (Modena 1729 - Pavia 1799) discovers hermetic sealing as a means of preserving food. Thus, Spallanzani reconfirms Louis Joblot 's microscopy results and extends them, establishing that microbes are never spontaneously generated. Nonetheless, spontaneous generation continued to find adherents until Louis Pasteur's 1862 paper.

1766 The eccentric Henry Cavendish (Nice 1731 - Clapham 1810) discovers "inflammable air" (hydrogen) (Three Papers, Containing Experiments on Factitious Air). He investigates its properties. He shows that it produced a dew, which appeared to be water, upon being burned. Although performed well before the experiments of Lavoisier, this remains well within the phlogiston paradigm.

1766 Leonhard Euler (Basel 1707 - St Petersburg 1783) the mathematician, suggested a design for achromatic lenses.

1766-1784 Controversy between John Needham and Lazarro Spallanzani over spontaneous generation.

1767 The Commentarius de formatione cordis in ovo incubato crowns Albrecht von Haller’s embryological studies. In all of Haller’s writings self-criticism and revision are inescapable choices and his work was developed out of a total of 458 «protocols» of observations; it was written in Latin, consigned to print in French, and re-elaborated in Latin in the final version. The itinerary of the author who, at the height of his scientific maturity, suspended judgement on the theory of generation which he then supported (epigenesis), sought confirmation of his new ideas through experimentation, and sensationally overturned his original hypothesis, endorsing the opposing theory (preformism) with his authority plus an enormous mass of corroborating data Elementa Physiologiae Corporis Humani, is exemplary.

1768 Lind publishes An Essay on Diseases Incidental to Europeans in Hot Climates : with the method of preventing their fatal consequences.

1769 Denis Diderot (Langres 1713 - Paris 1784), in Le Rêve de d'Alembert, deals with, among other things, animal reproduction, mutation, eugenics, the mechanical system of the body, and the nervous system.

1770 Bonnet's La palingénésie philosophique : ou Idées sur l'état passé et sur l'état futur des êtres vivans : ouvrage destiné á servir de supplément aux derniers écrits de l'auteur et qui contient principalement le précis de ses recherches sur le christianisme summarizes all his theories, in particular his views on préformation.

1770 Paul-Henri Thiry d'Holbach (1723-1789) publishes his Système de la nature: ou Des loix du monde physique et du monde moral, denying any cosmic divine plan in nature.

1770-1775 Joseph Priestley (Leeds 1733 - Northumberland 1804) discovers that a component of air is consumed by animals and produced by plants.by heating mercuric oxide. He explains his discovery within the paradigm of the four elements, naming it "dephlogisticated air" which he obtains by heating up cinabar (mercury oxide: after Lavoisier it will be known to be oxygen). He summarizes his work in Experiments and observations on different kinds of air. The explanatory paradigm is still that of the four elements amended by the phlogiston theory.

1770-1786 Carl Wilhelm Scheele (Stralsund 1742 - Köping 1786)describes in his Chemische Abhandlung von der Luft und dem Feuer (Chemical Observations and Experiments on Air and Fire) isolating citric, malic, lactic, and uric acids and glycerol from natural sources and produces, and before Priestley a new type of air (now known to be oxygen). Common air, when freed from "aerial acid" (carbon dioxide) and water vapor, consists of two gases: "fire air" (oxygen) which supports combustion, and "foul air" (nitrogen), which does not. Scheele was an adherent of the phlogiston theory, and he accounted for oxygen's combustibility by describing it as peculiarly attractive to phlogiston.

1771 Cotugno publishes De sedibus variolarum syntagma, a treatise on fevers and smallpox.

1771 In his Experimental inquiries : part the first : containing an inquiry into the properties of the blood : with remarks on some of its morbid appearances : and an appendix, relating to the discovery of the lymphatic system in birds, fish, and the animals called amphibious, anatomist William Hewson (Hexham 1739 - London 1774) details his research on blood coagulation, including his success at arresting clotting and isolating a substance from plasma he dubs "coagulable lymph." The substance is now known as fibrinogen, a key protein in the clotting process.

1771 Luigi Galvani (Bologna 1737 - 1798) produces current electricity.

1772 Priestley and Daniel Rutherford independently describe "residual air" (nitrogen). Priestley presents his work later published as Experiments and observations on different kinds of air to the Royal Society. This is a complementary description to that proposed by Cavendish. It is still within the paradigm of the four elements.

1772 John Walsh (1726-1795) conducts experiments on the torpedo (electric) fish Torpedo marmorata.

1772 Priestley and Jan Ingen-Housz (Breda 1730 - Bowood 1799) investigate photosynthesis. Ingenhousz explores how plants could contribute to salubrity of the atmosphere. Ingen-Housz develops a technique that prevents evaporation under the microscope by placing the drop of liquid of interest between two flat transparent slides.

1773 Fothergill describes trigeminal neuralgia ("tic douloureux", Fothergill's syndrome).

1773 Priestley discovers nitrous oxide (not yet understood within the atomist paradigm).

1773 Preoccupied by the problem of human alimentation and familiar with replacement vegetables for the usual ones, Antoine Augustin Parmentier (1737 - 1813) proposes to generalise the cultivation of potatoes.

1773 Hilaire Marin Rouelle (1718 - 1799) isolates urea from urine.

1773-1786 Otto Frederick Müller (Copenhagen 1730 - 1784) a Danish naturalist, visualizes with the microscope the micro-organisms today known as bacteria with sufficient clarity to separate them from protozoa. He divides them into two distinct morphological types. He coins the terms bacillum and spirillum. He also is the first to make a general classification of micro-organisms, following the scheme of Linnaeus. In 1786, with Otto Fabricius (1744 - 1822) he publishes a remarkable work on Animalcula infusoria; fluvia tilia et marina where ciliates are so well described that they can easily be identified today.

1774 Antoine-Laurent de Jussieu (Lyon 1748 - Paris 1836), member of a family which gave many distinguished scientists, exposes in his book Genera plantarum secundum ordines naturales disposita, juxta methodum in Horto Regio Parisiensi exaratum, anno M.DCC.LXXIV (published in 1789) his ideas of plant classification, used until now. Against Linné, Jussieu stresses the significance of the morphological organization of organisms.

1774 Although he was aware of the fact that there is no anatomical connection between the adrenal glands and the gonads, Johann Friedrich Meckel (1714-1774) associates the adrenal glands with sexual function.

1774 Franz Anton Mesmer (Iznang 1734 - Meersburg 1815) introduces "animal magnetism" (later called hypnosis).

1775 William Withering (Wellington 1741 -1799) is the first to use digitalis as a diuretic.

1775  Peter Christian Abildgaard (1740 - 1801) examines the life cycle of the tapeworm and finds that he needs more than one host to its reproductive cycle.

1775 Johann Friedrich Blumenbach (Gotha 1752 - Göttingen 1840), in De generis humani varietate nativa defines the fourfold division of the human family still often in use today, based on geological variables (Mongolian, American, Caucasian, and African). Later on, in his third edition (1795), he adds a fifth geological variation, the Malayan.

1776 Giacinto Vincenzo Malacarne (Cuneo, 1744 - Padova, 1816) publishes a book solely devoted to the cerebellum Nuova esposizione della vera struttura del cerveletto.

1776 Spallanzani repeats Leeuwenhoek's descriptions of spermatozoa.

1777 Adair Crawford (Antrim 1748 - Lymington 1795) publishes the first experiments on animal calorimetry, comparing heat production in a guinea pig with combustion (Experiments and observations on animal heat, and the inflamation of combustible bodies : being an attempt to resolve these phaenomena into a general law of nature).

1777 Antoine Laurent (de) Lavoisier (1743 - 1794), an important government official, in charge of Powders for the Royal Arsenal, demonstrates that air is made up mostly of oxygen and nitrogen. This is a complete change of paradigm, abandoning Empedocles' four elements and changing the ideas about Nature into was to become the atomic theory later developed by John Dalton. Lavoisier further reports that the experiments he performed with Trudaine de Montigny prove that the vermilion colour of blood comes from oxygen binding. He proposes that this is analogous to the red colour of mercuric oxide. He also proposes that respiration is a kind of combustion, evolving heat.

1777 Petrus (Pierre) Camper (Leyden, 1722 - 1789) who practiced as a surgeon, develops comparative anatomy studies, of man in particular. He also studies animal diseases. Visiting Paris for four months he delivers a lecture on the facial angle of primates. He contends that the facial angle variation demonstrates that humans have considerable variation in their anatomy. His study, however, was later used as a means to differentiate human races.

1778 Buffon publishes a supplement to his Histoire Naturelle: Examen impartial des Epoques de la Nature where he proposes a novel history of the Earth, split into six "epochs", each of 75,000 years. This is perceived at the time as a blasphemy against the content of the Bible and triggers the first scientific discussion on the origin and development of the Earth.

1778 Wilhelm Friedrich Freiherr Von Gleichen-Russworm (1717 - 1783) stains what is now known as bacteria with indigo and carmine (Abhandlung über die Saamen - und Infusionsthierchen, und über die Erzeugung, nebst mikroskopischen Beobachtungen des Saamens der Thiere in verschiedenen Infusionen).

1778 Louis Jean Marie Daubenton (1716-1800), collaborator of Buffon, is nominated at the Collège de France. He develops many different fields, in particular comparative anatomy. Rather than stress pure description of animals, Daubenton emphasizes the need to consider each animal in respect of its most vital organs (skeleton, heart, brain, respiratory, digestive, excretive and sexual organs) and the results thus obtained be compared.

1778 Paul Joseph Barthez (1734 -1806) publishes his treaty with a striking title Nouveaux élémens de la science de l'Homme. In his introduction he gives a definition of causality, then demonstrates that life needs a special principle, present in all its forms. He advocates Stahl's phlogiston theory. His epistemological approach is not unlike the one that dominates today's genomics: collecting a large number of facts, that are grouped to try to guess their causes, with the risk to group everything under a single principle, the "vital principle" for Barthez, "complexity" today. His modernity continues in his posthumous Treaty of beauty in nature and the arts.

1778 Lavoisier demonstrates the chemical nature of animal respiration.

1778 François Marie Arouet de Voltaire (Paris 1694 - 1778) publishes his Lettres philosophiques where he discusses at length the physics of his time, shortly before his death. Death of Jean-Jacques Rousseau.

1779 Antonio Scarpa (1752-1832) describes Scarpa's ganglion of the vestibular system.

1779 Torbern Olof Bergman (1735-1784) publishes his elements of chemistry: Opuscula physica et chemica, immediately translated into French by Louis-Bernard Guyton de Morveau (Dijon, 1737 - Paris, 1816).

1779 Blumenbach, founder of physical anthropology, classifies spermatozoa as Infusoria.

1779 Publication of Jan Ingenhousz's Experiments upon Vegetables: discovering their great power of purifying the common air in the sun-shine, and of injuring it in the shade and at night. To which is joined, a new method of examining the accurate degree of salubrity of the atmosphere showing that illumination is required for oxygen production in plants. He also shows that plants use carbon dioxide.

1780 Spallanzani performs experimental artificial fertilization in amphibians, silkmoth, and dog. He concludes from filtration experiments that spermatozoa are necessary for fertilization. Described cleavage in frog embryo.

1780 Lavoisier and Pierre-Simon Laplace (Beaumont-en-Auge 1749 - Paris 1827) publish their memoir on heat, in which they reach the conclusion that respiration is a form of combustion. Lavoisier's theories of combustion, his development of a new system of chemical nomenclature and the first modern textbook of chemistry led to him being known as the father of modern chemistry. As a scientist, Lavoisier demonstrated the nature of combustion, disproving the phlogiston theory, proposed the name "oxygen" for the substance previously known as dephlogisticated air, and laid the framework for understanding chemical reactions as combinations of elements to form new materials.

1780 Torbern Olof Bergman (1735-1784) establishes the list of carbonates, and introduces the concept of "elective affinities", which would be later developed by Goethe.

1780 Pierre Bertholon de Saint Lazare (1742-1800), friend of Benjamin Franklin publishes De l'électricité du corps humain dans l'état de santé et de maladie, a study on the effects of electricity on the human body and tries to use it to cure diseases.

1781 Peter Christian Abildgaard (1740 - 1801) investigates the life cycle of a tapeworm and finds that it requires more than one host.

1781 Johan Christian Fabricius (1745 - 1808) devises a new classification of insects, following the rules established by Linné (Species insectorum : exhibentes eorum differentias specificas, synonyma auctorum, loca natalia, metamorphosis, adjectis observationibus, descriptionibus).

1781 Marie Jean Antoine Nicolas de Caritat de Condorcet (1743 - 1794) publishes his Essai sur l'application de l'analyse à la probabilité des décisions rendues à la pluralité des voix, a treaty which pioneers game theory and many aspects of population genetics.

1781 According to standard historical reports, Felice Fontana (Pomarolo, 1730 - Firenze, 1805) describes the structure now named the nucleolus, after finding it in the cells of the slime from an eel's skin. Whether he truly identified this structure remains controversial. He also describes the microscopic features of the axoplasm.

1782 Guyton de Morveau names the gas isolated by Priestley in 1774 from nitrogen and/or hydrogen (alcali volatil) ammoniac.

1783 Spallanzani extends Réaumur's findings to other birds, small mammals, and finally to humans by using himself as an experimental animal. Digestion is clearly shown to be a chemical process rather than a mechanical grinding of the food.

1783 Luigi Galvani develops the first electric cell from two strips of metal and the fluids from a dissected frog, and determines that the energy must proceed from the frog. Later on he finds that electricity can make muscles contract.

1784 René Just Haüy (1743 - 1822) publishes a theory of crystals as constituted from repeating three-dimensional units, "molécules intégrantes" (integral molecules) (Essai d'une théorie sur la structure des crystaux appliquée à plusieurs genres de substances crystallisées).

1785 The Experiments on Air by Henry Cavendish continues to develop the phlogiston paradigm to explain the chemical behaviour of air.

1785 Ingenhousz (Breda 1730 - Bowood 1799) describes the irregular motion of coal dust particles on the surface of alcohol, randomly zigzagging  during the course of evaporation. This process was erroneously identified as similar to the process, known as Brown's motion, discovered  several decades later on by Brongniart and by Robert Brown.

1785-1797 For twelve years Marcus Elieser Bloch (1723 - 1799), having assembled the most important collection of fishes in the world (some 1500 fishes), in Berlin, publishes an extraordinary Ichtyologie ou histoire naturelle générale et particulière des poissons. The collection still exists at the Museum für Naturkunde der Humbolt Universität.

1786 Rediscovering what Swammerdam had found in 1658, Luigi Galvani shows that the nerves transmit electricity, and that it is possible to control the motor nerves of frogs using electrical currents (Sulle forze dell'elettricità nel movimento muscolare).

1786 In hisTraité d'anatomie et de physiologie Félix Vicq d'Azyr (Valognes 1748 - Paris 1794) after discussing at length the significance of classes in biology, describes the locus coeruleus and the red nucleus and writes several comparative anatomy studies. In this treaty he divides natural objects into three kingdoms (minerals, plants and animals) and divides the functions of life into 9 categories (digestion, nutrition, circulation, respiration, secretion, ossification, generation, irritability and sensitivity). These functional categories could well serve as a basis for today's discussion on the classification of functions in genomics.

1787 Irénée du Pont, apprentices as a bookkeeper to Lavoisier and becomes commissioner of Powders. Over the three years he was with Lavoisier at the Royal Arsenal, Irénée had been exposed to the art of gunpowder making. Lavoisier, who was responsible for changing French gunpowder from the very worst to the very best in the world, then offered the young Irénée a job at the powder factory outside of Paris.

1788 Jean Senebier (Genève 1741 - 1809) shows that it is the light and not the heat of the sun that is effective in photosynthesis.

1788-1804 Bernard Germain Etienne de La Ville-sur-Illon, comte de Lacépède (Agen, 1756 - 1825) writes a follow-up of Buffon's Histoire Naturelle.

1789 Beginning of the French Revolution. Antoine-Laurent Lavoisier publishes his Traité élémentaire de Chimie (Elements of Chemistry), in which fermentation is described as the splitting of sugar into alcohol and carbon dioxide. He characterizes the reaction as an oxidation-reduction reaction. Lavoisier and Armand Séguin (1767-1835) make the first measurements of human metabolic rate.

1789 Erasmus Darwin 's (Nottingham 1731 - 1802) , in "The Loves of the Plants," from The Botanic Garden exposes the linnean classification, This book from the grandfather of Charles Darwin and Francis Galton advanced the idea that environmental influences transformed the descent of living species.

1789 The Marquis Pierre Simon de Laplace, publishes his laws of the planetary system where he states the mechanic principles of the Universe.

1790 Lavoisier develops a table of thirty-one chemical elements.

1790 Immanuel Kant (Königsberg (Kaliningrad) 1724 - 1804), in his Kritik der Urtheilskraft, states that the analogy of animal forms implies a common original type and thus a common parent.

1790 Johann Wolfgang von Goethe (Frankfurt-am-Main 1749 - Weimar 1832), in Versuch die Metamorphose der Pflanzen zu erklären, looking for universals tries to discover the primal plant, and coins the word morphology.

1791 William Smith (Churchill 1769 - Northampton 1839) points out the relationship between fossils and geologic strata. He works out a method for estimating geologic age, and lays the foundation of stratigraphic geology.

1791 Jean Senebier (1742 -1809) in Swizerland reports in the Encyclopédie Méthodique (Physiologie végétale, t.1, Paris) that olive oil kept in air lost its fluidity and went rancid, while another sample not exposed to air remains unmodified.

1791 Philippe Pinel (1745 - 1826) publishes his Traité médico-philosophique sur l'aliénation mentale.

1792 The controversy between Luigi Galvani and Alessandro Volta (Como 1745 - 1827) over the twitching of frogs' legs leads to an interest in investigating the electrical phenomena of animals.

1792 Antoine François de Fourcroy (1755 - 1809)'s Philosophie chimique, ou Vérités fondamentales de la Chimie Moderne, disposées dans un nouvel ordre attracts considerable attention and is translated in many languages. In this work an attempt is made at characterizing the chemical composition of plants and animals (the latter being richer in azotic content). The vegetable elements are divided into sixteen separate substances, including gum, sugar, fatty and fugitive oils, resin etc. The animal substances are albumen, lime and fibrin. A characteristic of both is the process of fermentation and putrefaction.

1793 Publication of Christian Konrad Sprengel (1750–1816)'s Das Entdeckte Geheimnis der Natur im Bau und in der Befruchtung der Blumen, pointing out the role of insects and of the wind in the cross-pollination of plants.

1793 Yellow fever epidemic in Philadelphia, USA.

1794 John Dalton (Eaglesfield 1766 - Manchester 1844) describes color blindness, a condition from which himself suffered: color blindess is also called "Daltonism."

1794 Samuel Thomas von Sömmering (Thorn 1755 - Frankfurt-am-Main 1830) first rosicrucian and alchemist becomes a reputed anatomist, compiling a treatise on the anatomy of the human body (including study of monsters), De corporis humani fabrica. In his Über das Organ der Seele (1796, dedicated to Kant) he gives a detailed description of the brain and the nerves and localizes the functions of the soul in the cerebrospinal fluid.

1794 Dell'Uso e dell'attivita dell'Arco Conduttore nelle Contrazione dei Muscoli, published in Bologna by Galvani is the most important of all published documents in the history of animal electricity, describing for the first time the seond experiments of Galvani without metals, which established the existence of electrical forces within living tissues.

1794 When the Reign of Terror erupts in France, Lavoisier falls victim to its tyranny and is beheaded. The justification for this act was that "La République n'a pas besoin de savants", a slogan much similar to those found during the Cultural Revolution in China. The du Ponts leave for America, bringing with them the memory of their friend and the seeds of a great new American enterprise (DuPont de Nemours).

1794-1796 Erasmus Darwin's Zoonomia; or the laws of organic life is published; there he ridicules Bonnet's incapsulation theory and after having proposed that "warm-blooded animals have arisen from one living filament...possessing the faculty of continuing to improve by its own inherent activity, and of delivering those improvements by generation to its posterity." he also suggests that the conflict between males over which "should propagate the species" is the final cause explaining that the species "become improved".

1795 James Hutton (Edinburgh 1726-1797)'s Theory of the Earth is published, interpreting certain geological strata as former sea beds.

1795 Through the efforts of Sir Gilbert Blane (1749 - 1834), lemon juice is officially ordered as part of naval rations by the Admiralty.

1795 Alexander Gordon (Aberdeen 1752 - 1799) demonstrates the contagiousness of puerperal fever (A Treatise on the Epidemic Puerperal Fever of Aberdeen).

1795 -1810 The controversy between Swammerdam or Spallanzani and those believing in spontaneous generation, such as Buffon, Needham or Lamarck was momentarily settled by boiling broths in which life used to appeared. Nicolas François Appert (Châlons-sur-Marne 1750 - Massy 1841) the chef who invented the still commonly using hermetical inspissation of food shows, in a 15 years experimentation that this preserves food indefinitely. However it is soon proposed that this is due to the lack of oxygen in the hermetic jars, and since oxygen is required for life, rather than putting the idea aside, this gives fresh impetus to the idea of spontaneous generation.

1796 Johann Christian Reil (1759 - 1813) starts the journal Archiv für Physiologie, and describes the insula (island of Reil). In his essay published there Von der Lebenskraft, he speculates about the origin of life as deriving from a general property of growth, the seed and the egg being dead but gaining life through infusion of a fire-like warm element. He produces a definition of "organ", which was subsequently of much use.

1796 Jan Ingenhousz concludes that plants utilize carbon dioxide in their nutrition. He understands that plants carry on respiration concomitantly with photosynthesis.

1796 Edward Jenner (Berkeley 1749 - 1823) uses a cowpox vesicle to variolate against smallpox.

1796 Georges Léopold Chrétien Frédéric Dagobert Cuvier (Montbéliard 1769 - Paris 1832), is invited in 1795 by Étienne Geoffroy Saint-Hilaire (Etampes 1772 - Paris 1844) to come to Paris; he is appointed an assistant, and shortly thereafter a professor of animal anatomy, at the newly reformed Musée National d'Histoire Naturelle. Cuvier stays at his post when Napoléon comes to power. In his Discours sur les révolutions du globe he attributes the succession of fossil forms to a series of simultaneous extinctions caused by natural catastrophes.

1797 Jean-Baptiste Pierre Antoine de Monet, chevalier de Lamarck (Bazentin-le-Petit 1744 - Paris 1829) publishes his Mémoires de physique et d'histoire naturelle, établis sur des bases de raisonnement indépendantes de toute théorie; avec l’explication de nouvelles considérations sur la cause générale des dissolutions ; sur la matière de feu ; sur la couleur des corps ; sur la formation des composés ; sur l’origine des minéraux, et sur l’organisation des corps vivans, lus à la première classe de l’Institut national dans ses séances ordinaires, suivis de Discours prononcé à la Société Philomatique le 23 floréal an V. In this work he endeavours to form a general theory of existence, in a way quite reminiscent of that of the Presocratic philosophers, combining physics, chemistry and physiology. There he attacks what he calls " la chimie pneumatique" that is, Lavoisier's quantitative chemistry. He thought it impossible (incompatible avec la raison) that oxygen would be both part of air and of water. Till his death, Lamarck stays away from the atomic theory, and remains within the paradigm of the four elements, with the "feu intérieur" playing the major role to shape the form of organisms. This is the reason of the continued misunderstanding between the transformism of Lamarck, based on an ancient theory of nature, and the post-atomist view of Darwin.

1798 Geoffroy Saint Hilaire collects plants an animals in Egypt during the expedition of Napoléon there.

1798 Publication of Thomas Robert Malthus (Rookery 1766 - Bath 1834)'s An Essay on the Principles of Population as it affects the future improvement of society with remarks on the speculations of Mr. Godwin, M. Condorcet, and other writers which has an immediate influence on social policy. Malthus establishes a simple demonstration that ultimately the population of mankind will outstrip its ability to provide enough supply for its survival.

1798 Barthez exposes a vitalistic theory of muscle contraction in his book Nouvelle méchanique des mouvements de l'Homme et des animaux.

1799 Humphry Davy (Penzance 1778 - Geneva 1829), inventor the safety lamp for miners, noting "the power of the immediate operation of the gas in removing intense physical pain." develops nitrous oxide and uses it for anesthesia.

1799 Alexander von Humboldt (Berlin 1769 - Berlin 1859) equips at his own expenses a journey of exploration to South America, which he explores so thoroughly that it was called the second discovery of America.

1799 Pierre François-Xavier Bouchard (1772 - 1832), a young officer of military engineering, in the course of earthwork at Fort Julien, near the village of Rachid (Rosette) discovers a black stone reused in a wall. He signals his finding to General Menou, who transports the stone to Alexandria. This stele carries the copy of a decret of Ptolemeus V Epiphanes, in hieroglyphics (upper inscription), in demotic (the 32 lines at the center) and in Greek (the lower 54 lines). Copies were immediately made: Joseph Marcel, applied his "autography" method, Nicolas Conté uses the stele for charcoal rubbing on paper and Adrien Raffeneau-Delille makes a molding using sulfur. The stone is stolen by the English when General Menou capitulates in Alexandria in 1801. It is now exposed at the British Museum.

1799-1806 Joseph Marie Proust (Angers 1754 - 1826), pupil of GF Rouelle, establishes that the proportions of chemical reactions are always constant.