MAXWELL, MENDEL, PASTEUR 1850-1874

The industrial revolution 1850-1874

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1850 Augustus Volney Waller (Faversham 1816 - 1870) describes the microscopic appearance of degenerating nerve fibers after an axon is cut. This made it possible to trace the course of fibers through the nervous system and demonstrated the importance of the nucleus in the regeneration of nerve fibers. This process was subsequently termed "Wallerian degeneration".

1850 Extending Matteucci's observations, Emil du Bois-Reymond observes that muscle and nerves of animals during their state of activity produce electric currents which can be measured with the aid of the usual apparatus of electrophysics, the galvanometer. He records a resting electrical current in relaxed muscle and shows that this current diminishes when the muscle contracts. DuBois-Reymond terms this negative fluctuation in the current an "action potential".

1850-1855 Claude Bernard (Saint-Julien 1813 - Paris 1878), the successor of Magendie at the Collège de France, isolates glycogen from the liver, shows that it is converted into blood glucose, and discovers the process of gluconeogenesis.

1850-1855 Jean-Baptiste Boussingault (Paris, 1802 - Paris 1887) who had proved that the carbon in plants came from atmospheric CO₂, proposes that plant nitrogen comes from the soil. demonstrates that higher plants cannot utilize atmospheric nitrogen, but only nitrates from the soil. He also demonstrates the necessity of nitrogen for plants and animals. His experimental results were not conclusive, however, and conflicting data were soon published by another Parisian chemist, Georges Ville (1824 - 1897), and popularized by Liebig. The question he resolved was whether the nitrogen that plants need to grow came from the soil or from the air. Joseph Priestley had argued, in the 18^th century, in favor of the air, and his opinion was seconded in the early 19^th century, by Liebig, then the world's most famous chemist.

1851 Heinrich Müller (1820 - Würzburg 1864) is the first to describe the coloured pigments in the retina.

1851 Pasteur publishes a memoir on aspartic and malic acids.

1851 Marchese Alfonso Corti (1822 - 1876), using a microscope, discovers that the inner ear is filled with fluid and that the tiny hair cells are the true sensory elements of the inner ear on a structure later named "organ of Corti".

1851 Theodore Maximillian Bilharz (1825 - 1862) working at the Kasr-el-Aini hospital in Cairo describes schistostomiasis, often named after him "bilharziose".

1851 Helmholtz invents the ophthalmoscope.

1852 Rudolf Albrecht von Kölliker (1817 - Würzburg 1905), Swiss anatomist and physiologist, publishes an influential textbook on cell theory, the Handbuch der Gewebelehre des Menschen (Manual of Histology). He later published a text on embryology, in which he interpreted the developing embryo in terms of the cell theory.

1852 In association with Kölliker, Karl Theodor Ernst von Siebold (1804-1885) creates the journal Zeitschrift für wissenschaftliche Zoologie, where the latter describes for the first time the schistosome parasite. Elie Mechnikov, later, studied in his laboratory.

1852 Auguste Comte uses the concept of altruisme (perhaps created by his teacher Andrieux) later used in sociobiology and in population biology.

1852 Helmholtz measures the speed of nervous impulses.

1852 François Rémy Lucien Corvisart (1824-1882) coins the term tétanie to describe the contraction induced by tetanos or other diseases with similar clinical sign.

1852 Gottlob Friedrich Heinrich Küchenmeister (1821- Dresden 1890) identifies the cause of cysticercosis by feeding infected rabbits to dogs. He demonstrates that bladderworms are the preadult forms of taeniid cestodes. To prove his theory of dead end taenia development, he later made experiments on prisoners, feeding them infected pigs, which was deeply resented by some of his contemporaries. This experimental approach will unfortunately be widespread for many decades.

1852 Hermann Friedrich Stannius (1808 - 1883) ties ligatures between the sinus venosus (the heart pace maker) and the atrium, and between the auricles and the ventricles of a frog heart, and demonstrates that the sinus is the pacemaker of the heart, yet the auricles and ventricles are capable of independent, spontaneous contractions.

1852 Karl Friedrich Wilhelm Ludwig (Hessen 1816 - Leipzig 1895) summarizes his views on physiology (using the graphical method he invented to measure fluxes) in his Lehrbuch der Physiologie des Menschen. In this book he starts with the Physiologie der Atome where he stresses the importance of basic chemistry in life. Then follows a chapter on Physiologie der Aggregatszustände which deals with dissolution, diffusion and currents. Thus, in parallel with the other major physiologist of his time, Claude Bernard, he sees life as a physico-chemical process.

1852 Kölliker describes how motor nerves originate from the neurons in the anterior horn of the spinal cord.

1852-1864 Émile Blanchard (1819 - 1900) publishes his treaty L'organisation du règne animal where he describes the various classes of animals.

1853 Pasteur, in a series of memoirs, discovers the origin of racemic acid and shows how tartaric acid can become racemic acid. He also discovers the action of tartaric acid on polarised light. After having been the first to report the production of the cinchona toxines (cinchotoxine and quinotoxine) by mild acid treatment of the cinchona alkaloids, Pasteur employs optically active D-quinotoxine to carry out the first optical resolution ever made.

1853 Stanislas Martin (?- 1886?), in his Physiologie des substances alimentaires ou histoire physique, chimique, hygiénique et poétique des aliments : avec leur étymologie grecque, celtique, latine et leurs dénominations en langues allemande, anglaise, espagnole et italienne describes the nutrition power and sapidity of food and nutrients, starting a type of research which is nowadays very fashionable. He triggers chemical investigation of the products found in usual and unusual food as possible drugs.

1853 Ludwig Karol Teichmann (1823 - 1895), in Krakow, Poland, develops the first microscopic crystal test for hemoglobin using hemin crystals. This test has since been much used in forensic medicine.

1853 George Meissner (1829 - Göttingen 1905) describes sensory nerve endings later known as "Meissner's corpuscles".

1854 Heinrich Schröder (1810 - 1885) and Theodor von Dusch (1824 - 1890), and subsequently, Schröder alone in 1859 repeats Helmholtz filtration experiment and show that living particles can be removed from air by filtering it through cotton-wool.

1854 Antoine Béchamp (1816-1908), later author of a fanciful theory on the origin of microbes, and after the work of many precursors, establishes the correspondence between yeast and a substance, zymase, in fermentations.

1854 Pasteur in turn discovers the microbial fermentation of beet sugar, but with a very vague characterization, and Béchamp accuses him of plagiarism. This will be the beginning of a controversy with Claude Bernard until the latter's death.

1854 Louis Pierre Gratiolet (1815 - 1865) traces visual radiation from thalamus to occipital cortex and describes convolutions of the cerebral cortex (Mémoire sur les Plis Cérébraux de l'Homme et des Primates. Paris: Bertrand)

1854 Snow shows that the London cholera epidemic is caused by one single pump.

1854 Filipo Pacini (1812 - 1883) isolates the organism responsible for cholera, now known as Vibrio cholerae.

1854 Gustave Adolphe Thuret (Paris 1817 - Nice 1875) while making experiments in Cherbourg, demonstrates with Fucus that fecondation results from the fusion of a male and a female gamete and publishes his work in Recherches sur la fécondation des Fucacées (follow up in 1958).

1855 Bartolomeo Panizza (1785 - 1867) publishes his Osservazioni sul nervo ottico (Observations on the Optic Nerve) where he shows the occipital lobe is essential for vision.

1855 Claude Bernard states that all organs liberate into the tissue fluids special substances which assist in maintaining the constancy of the milieu intérieur (internal environment). This was later known as hormonal factors.

1855 Richard Heschl (1824 - 1881) describes the transverse gyri in the temporal lobe (primary auditory cortex, Heschl's gyrus).

1855 Having discovered a disease caused by insufficiency of the adrenal cortex in 1849, Thomas Addison (1793 – 1860) describes the syndrome associated with the deterioration of the human adrenal cortex (Addison's disease) and later pernicious anemia (Addison's anemia).

1856 Nathanael Pringsheim (1823 – 1894), founder of the German Botanical Society and the Jahrbücher für wissenschaftliche Botanik, observes pollen penetration of the egg of Oedogonium.

1856 Corvisart describes trypsin and uses pepsin therapeutically.

1856 Valine is isolated by Eugen Franz Freih von Gorup-Besanez (1817 - 1878).

1856 William Henry Perkin (1838 - 1907) prepares the first of the aniline dyes, eosin. This dye would later prove useful for selective staining cytoplasmic proteins.

1856 Edmé Félix Alfred Vulpian (1826 - 1887) applies a solution of ferric chloride to slices of the adrenal glands and notes that the medulla stained green while the cortex did not. He also notes that the same reaction is given by samples of venous blood leaving the adrenal, but not by arterial blood entering the gland. To account for these observations, he assumed that the medulla synthesized a substance that was liberated into the circulation.

1856 Karl Ludwig develops perfusion techniques for keeping animal organs alive after their removal from the body. He also invented the kymograph, mercurial blood pump and a device for measuring the rate of blood flow. Ludwig is the first to study the role of the nervous system in blood flow as well as secretory functions.

1856 Workers quarrying for limestone in the Neander Valley (Thal in German) near Düsseldorf discover the first Neanderthal remains.

1857 Kölliker discovers "sarcosomes" (mitochondria) in muscle cells.

1857 Claude Bernard and independently Ernst Felix Immanuel Hoppe-Seyler (Freiburg 1825 - 1895) study the competitive binding of oxygen and carbon monoxide on cruorine (hemoglobin).

1857 Franz Leydig (Rothenburg, 1821 - Bonn 1908) Professor of Histology in Würzburg and later in Tübingen and Bonn, the founder of Comparative Histology describes the interstitial cells of the testis (Leydig's Cells) in his Lehrbuch der Histologie des Menschen und der Thiere.

1857 Henri Étienne Sainte-Claire Deville (St. Thomas Antilles 1818 - Boulogne 1881) establishes thermal dissociation of chemicals.

1857 Claude Bernard demonstrates the formation and decomposition of glycogen by the liver. This is the first demonstration of a catabolic process.

1857 After a memoir on amylic acid, Pasteur's Mémoire sur la fermentation appelée lactique demonstrates that lactic acid fermentation is carried out by living bacteria. This memoir is considered as the founding paper of the science of Microbiology. Interestingly this same year Pasteur's application is refused by the French Académie des Sciences.

1858 Stanislao Cannizzaro (Palermo 1826 - Roma 1910) develops the study of organic chemicals, and demonstrates the validity of Avogadro's number. Before that time most chemists would represent the structure of water as OH, assuming that the atomic number of oxygen was 8. Since the work of Cannizzaro all chemists would represent water as H2O, and 16 as the atomic mass of oxygen.

1858 Félix Joseph Henri de Lacaze-Duthiers (1821 - 1901) assistant of Milne-Edwards, professor in Lille, then Paris, finds that three Mediterranean mollusks produce purple-blue dyes. One, Murex trunculus, is determined by him (and other scientists, archeologists and historians) to be the source of the ancient Biblical blue. He creates the Stations de Biologie Marine at Banyuls and Roscoff in France, where many reknown biologists were later to work. La science n'a ni religion ni politique was the motto written on the door of his laboratory.

1858 Jean Louis Armand de Quatrefages de Bréau (Berthezène, 1810 - Paris, 1892) describes a silkworm disease, which he calls pébrine. We now know that it is caused by a parasite of the family of Microsporidia, Nosema bombycis. Quatrefages, quoted in Darwin's Descent of Man, is known for his development of evolutionary racism and support of the sect of Theosophy.

1858 George Bentham (1800 - 1884) publishes his Handbook of the British Flora. A description of the Flowering Plants and Ferns Indigenous to or Naturalised in the British Isles which was reprinted many times and is commonly present in british families.

1858 Pasteur notes that Penicillium molds ferment only dextrotartaric acid and do not attack the levo isomer. Thus he develops a practical method for separating compounds which are identical except for the spatial arrangement of the substituent group. More importantly this tells him that life processes are original : "La dissymétrie c'est la vie".

1858 Carmine, a commercially available red basic stain, is found to stain cell nuclei more intensely than the cytoplasm.

1858 Rudolf Virchow (Schivelbein (now Swidwin) 1821 - Berlin 1902) supports the notion that all cells arise from pre-existing cells, reviving the expression possibly coined by Raspail in 1825: "Omnis cellula e cellula" and applies the cell theory to problems of pathology and disease and set forth the illuminating principle that the outward symptoms of disease are merely the reflections of impairment at the level of cellular organization. Later on he would be critical of the view that epidemic diseases could be caused by living agents.

1858 Friedrich August Kekulé von Stradonitz (Darmstadt 1829 – Bonn 1896) proposes that carbon atoms can form chains and develops a structural theory based on two-dimensional arrangement of atoms and bonds.

1858 Philip Lutley Sclater (1829-1913) founds Ibis, the journal of the British Ornithological Union and studies the geographical distribution of birds.

1858 Joint announcement by Charles Darwin and Alfred Russel Wallace (Usk 1823 - Broadstone 1913) of the theory of natural selection.

1858 The botanist Karl Wilhelm von Nägeli (Kilchberg, Swizerland 1817 - München 1891) introduces the concept of micelles, to account for the "glue-like" behaviour of certain compounds.

1858 Garlic’s role in fighting disease was recorded in China almost 15 centuries earlier. Pasteur describes garlic’s antimicrobial qualities again.

1859 Darwin's On the Origin of Species argues for natural selection as a factor in organic evolution. More importantly, it establishes evolution as an acceptable theory in the minds of most naturalists. Most later interpretations of his views mistakenly attributed to him a major role of chance in the process of evolution, because he used the concept in a loose manner. Yet, Darwin himself corrected this view, explicitly writing: "I have hitherto sometimes spoken as if the variations so common and multiform in organic beings under domestication, and in a lesser degree in those in a state of nature had been due to chance. This, of course, is a wholly incorrect expression, but it serves to acknowledge plainly our ignorance of the cause of each particular variation. Some authors believe it to be as much the function of the reproductive system to produce individual differences, or very slight deviations of structure, as to make the child like its parents. But the much greater variability, as well as the greater frequency of monstrosities, under domestication or cultivation, than under nature, leads me to believe that deviations of structure are in some way due to the nature of the conditions of life, to which the parents and their more remote ancestors have been exposed during several generations." a view that is certainly sharing Lamarck's view of evolution, rather than the much earlier vision of Empedocles, who advocated generation of animals following a process of variation followed by survival of lucky monsters.

1859 Adolf Wilhelm Hermann Kolbe (1818-1884) synthesizes salicylic acid from phenol.

1860 Albert Niemann (1834-1861) purifies cocaine and later introduces it as a tonic/elixir in a patent.

1860 Gustav Theodor Fechner (Gross-Särchen 1801 - Lipsia 1887) in his Elemente der Psychophysik develops what was later known as "Fechner's law", a psychophysical generalization that states that the intensity of subjective sensation increases as the logarithm of the stimulus intensity.

1860 Pasteur states his aphorism, "Omne vivum e vivo." He starts his long series of experiments on the "Générations dites spontanées". In his two lectures dedicated to J-B Biot, Recherches sur la Dissymétrie moléculaire des Produits organiques naturels, Pasteur describes the epistemological background of his discovery of the importance of dissymmetry in life. He clearly states how Science must proceed in a hypothesis-driven way, emphasizing that facts cannot exist as such, but can only be observed once a hypothesis about the nature of a phenomenon is formed in the mind of the scientist.

1860 Wallace claims that a sharp boundary exists between the Australian and Oriental faunal regions. The "Wallace line of faunal delimitation" separates the Philippines from the Sanghir Islands and Borneo from Celebs, and runs through part of the Malay Archipelago.

1860 Robert Wilhelm Bunsen (Göttingen, 1811 - Heidelberg, 1899) working with Kirchoff on the decomposition of light by prisms, needs a source of hot temperature which would not be luminous. To this aim he uses a burner developed by Faraday but known today as the Bunsen burner, most used in chemistry and in biology.

1861 Jean Louis René Antoine Édouard Claparède (1832 - 1871) discovers giant axons in annelid worms.

1861 John Stuart Mill (London 1806 - 1873) publishes Utilitarianism, which follows his System of Logic (1843) : " To the Deductive Method, thus characterized in its three constituent parts: Induction, Ratiocination, and Verification, the human mind is indebted for its most conspicuous triumphs in the investigation of nature. To it we owe all the theories by which vast and complicated phenomena are embraced under a few simple laws, which, considered as the laws of those great phenomena, could never have been detected by their direct study. (Logic, Book III. Chapter XI. Section 3). ", with a most factual view of knowledge and values.

1861 Bentham publishes the first flora of Hong Kong, Flora Honkongensis.

1861 Pasteur, Mémoire sur les corpuscules organisés qui existent dans l'atmosphère. He also discovers life in the absence of air: Animalcules infusoires vivant sans gaz oxygène et déterminant des fermentations. For the second time his application is rejected by the Académie des Sciences.

1861 Thomas Graham (Glasgow 1805 - 1869)'s work on understanding the colloidal state of matter advances the understanding of protoplasmic systems. At that time his theory was vitalist: he thought that colloids were endowed with energia (an elusive form of energy) while the crystalloid state was the static, inert condition of matter. He later discovered the chemical formula of ozone.

1861 Thomas Henry Huxley (Ealing 1825 - 1895), who had opposed Owen in his hypothesis that the cranium was derived from vertebrae coins term "calcarine sulcus". He nevertheless emphasizes, contrary to Darwin, that evolution can proceed in a saltatory fashion. As an example he uses the observation made by Réaumur of the existence of polydactyly. This was much later understood to be the result of mutations in an homeogene.

1861 Max Johann Sigismund Schultze (Freiberg 1825 - 1874) establishes the protoplasm concept and, after noting the essential similarity between the cell contents of protozoa, plants and animals, concludes that "the cell is an accumulation of living substance or protoplasm definitely delimited in space and possessing a cell membrane and nucleus." Four years later he will found the journal Archiv für mikroskopische Anatomie.

1861 Paul Broca (1824 - 1880) begins his famous series of conferences where he discusses cortical localization. Broca persuades the majority of his colleagues world-wide that there is a relatively circumscribed center, located in the posterior and inferior convolutions of the left frontal lobe (later named Broca's speech area), which is responsible for speech (langage articulé).

1861 The still discussed discovery of fossil remains of Archaeopteryx lithographica is made in jurassic limestone deposits in a stone quarry in Solnhofen, Germany.

1862 Having discovered that the green color of plants is distributed into corpuscles, Julius von Sachs (1832–1897) provides experimental evidence that starch is a product of photosynthesis.

1862 M Jodin (? - ?) publishes Du rôle physiologique de l'azote faisant suite à un précédent travail présenté à l'Académie dans la séance du 28 avril 1862 (CR Acad Sci 55: 612) where he describes that a solution where phosphate and carbon is present without nitrogen can support the growth of mycodermes. This is the first demonstration of microbial fixation of nitrogen.

1862 William Withey Gull (Thorpe Le Soken 1816 - 1890), who later described anorexia nervosa, gives the clinical signs of the spinal cord disease syringomyelia.

1862 Clémence Augustine Royer (Nantes 1830 - 1902) a self-educated thinker, publishes the French translation of Darwin's The Origin of Species, with an introduction where she advocates eugenic practices, and reaffirms a "progressist" view of races, against the common Christian protection of the weak: "Que résulte-t-il de cette protection inintelligente accordée exclusivement aux faibles, aux infirmes, aux incurables, aux méchants eux-mêmes, enfin à tous les disgraciés de la nature? C'est que les maux dont ils sont atteints tendent à se multiplier indéfiniment ..." ["What are the consequences of this inintelligent protection exclusively given to the weak, the disabled, the incurable, and even to the evil persons, in brief, to all those who had been disgraced by nature? Remember that the evils that affect them tend to multiply indefinitely...."]. This type of reflection was to have an important impact in the spread of the idea of natural selection within humans in France.

1862 William Thomson (Lord Kelvin) (Belfast 1824 - Glasgow 1907) using the theory of Jean-Baptiste Fourier on thermal conduction, computes the age of the solar system as 25 million years (later revised to 40 million years).

1862 James Clerk Maxwell (Edinburgh 1831 - Cambridge 1879) states "We can scarcely avoid the conclusion that light consists in the transverse undulations of the same medium which is the cause of electric and magnetic phenomena." Much of the laws governing electromagnetic fields owe to his work. He is also known for Maxwell's demon, which plays an important role in the definition of information (wrongly identified as directly related to entropy).

1862 Max Joseph von Pettenkofer (1818 – 1901) develops techniques for hygiene, in particular for improving the way we control the our gases exchanges. With an apparatus for analyzing respiratory gas exchange, thus making possible evaluation of energy consumption by the determination of respiratory quotients.

1862 Henry Walter Bates (1825 - 1892) observes mimicry (now known as batesian mimicry) of distasteful or poisonous brazilian butterflies, by harmless, palatable species, in the lepidoptera and suggests that the mimics are protected from predation because of their resemblance to the harmful species.

1863 Ivan Mikhailovich Sechenov (1829 - 1905), the father of Russian physiology, publishes Reflexes of the Brain.

1863 The word "scientist" is coined to complement that of "artist".

1863 Charles Naudin (Autun 1815 - Antibes 1899) at the Museum d'Histoire Naturelle in Paris, convinced of the reality of transformism, publishes a long article on plant hybridization. He notes that the variation between generations explains the outcome if "Tous ces faits vont s'expliquer naturellement par la disjonction des deux essences spécifiques dans le pollen et dans les ovules de l'hybride", a prescient view of Mendel's demonstration.

1863 Karl Remigius Fresenius (1818 - 1897) uses a solid culture medium (potato slices) for growing microorganisms.

1863 Casimir Joseph Davaine (1812 - Paris, 1882) discovers small stick-shaped formations in the blood of animals affected by anthrax and shows that the disease in sheep is caused by blood 'bacteridia'.

1863 Nikolaus Friedreich (1825 - 1882) describes a progressive hereditary degenerative Central Nervous System disorder (Friedreich's ataxia).

1863-1864 George Gabriel Stokes (1819 - 1903), a famous Irish mathematician and physicist records the optical spectra of "cruorine" (hemoglobin) during the process of respiration and reports two widely different spectra for the oxidised and non oxidised form. He also shows that the spectra are different when the animal part of the product is omitted. He concludes from his experiments that oxygen is weakly bound to the inorganic compound of the blood "cruorine".

1864 John Hughlings Jackson (Green Hammerton 1835 - London 1911), considered as the father of English neurology, describes the loss of speech after brain injury.

1864 Ernst Heinrich Haeckel (Potsdam 1834 - Jena 1919) the father of many terms still in use, outlines the essential elements of modern zoological classification.

1864 Jacques Boucher de Perthes (1788 - 1868) publishes, with a foreword by Charles Lyell L'Ancienneté de l'Homme. L'homme fossile en France, communications faites à l'Institut (Académie des Sciences).

1864 Schultze describes the fine cytoplasmic tubes that connect the protoplasts of adjacent plant cells by passing through their walls (plasmodesmata).

1864 Pasteur's demolishes the doctrine of spontaneous generation: "J'ai la prétention de démontrer avec rigueur que dans toutes les expériences où l'on a cru reconnaître l'existence de générations spontanées, chez les êtres les plus inférieurs, où le débat se trouve aujourd'hui relégué, l'observateur a été victime d'illusions ou de causes d'erreur qu'il n'a pas aperçues ou qu'il n'a pas su éviter. "

1864 Controversy between Nägeli and Robert Koch (Clausthal 1843 - Baden-Baden 1910) regarding the existence of two or more structural forms during their life cycle (pleomorphism) versus genetic distinctness of bacteria. This controversy was to last for eighty years, until it was discovered that bacteria behave as all living organisms do in terms of heredity.

1864 Hoppe-Seyler performs a variety of spectrometric records of the light absorption of the molecule, and the first crystallization of a "proteid" he names "hemoglobin". He states that this compound is composed of a globulin (not containing iron), associated to hematin (containing iron).

1865 Kekulé, announcing his discovery at a meeting of the Société Chimique in Paris, chaired by Pasteur, devises a ring model for the structural formula of benzene (a molecule discovered by Faraday in 1825), supposedly after dreaming about six monkeys holding one another by the tail.

1865 Karl August Möbius (1825 - 1908) and Heinrich Adolf Meyer create the modern system and methods of ecology in his study Die Fauna der Kieler Bucht.

1865 Franz Böhmer (? - ?) finds that the stain alum hematoxylin stains cell nuclei in blue to bluish-purple more strongly than their cytoplasm.

1865 Otto Friedrich Karl Deiters (1834-1863) differentiates dendrites and axons and describes the lateral vestibular nucleus (Deiter's nucleus).

1865 Jean-Antoine Villemin (Prey 1827 - Paris 1892) in his 5 December lecture at the Académie Impériale de Médecine in Paris, “Cause et nature de la Tuberculose“ demonstrates that, contrary to the opinion of the majority, that tuberculosis is contagious.

1865-1866 Karl Wilhelm von Kupffer (München, 1829 - München, 1902), Anatomist and Embryologist, Professor of Anatomy in Kiel (1867), in Königsberg (1875) and in Munich (1880) describes the "stellate cells" in the lining of blood channels in the liver (Kupffer's Cells) in the Archive für mikroscopische Anatomie.

1865-1867 Joseph Lister (1827 - 1912) institutes the practice of antiseptic surgery and the use of carbolic acid as a disinfectant.

1866 Thomas Clifford Allbutt (1836 - 1925) invents the clinical mercury thermometer, regretting that it is often used with the inconvenient Fahrenheit scale.

1866 Johann Gregor Mendel (Heinzendorf 1823 - Brno 1884) publishes his investigations of plant hybrids and their subsequent behavior. His fundamental discoveries lay forgotten for 34 years.

1866 Schultze, having discovered the existence of two types of receptor cells in the retina, formulates the so-called duplicity theory of vision. He had noticed that in diurnal birds the retina consisted mainly of cones but nocturnal birds possessed a retina with an abundance of rods. This led him to propose that cones must respond to colored light while rods should be more sensitive to black and white.

1866 Haeckel hypothesizes that the nucleus of a cell transmits its hereditary information. He first uses the term "ecology" to describe the study of living organisms and their interactions with other organisms and with their environment.

1866 Aleksandr Onufriyevich Kovalevsky (1840 - 1901) shows the similarity between the lancelet (Amphioxus lanceolatus) and the larval stages of tunicates and establishes the chordate status of the tunicates.

1866 Pasteur publishes his Etudes sur le vinaigre.

1866 Enrico Bottini (Stradella, 1835 - San Remo, 1903) introduces the use of phenic acid (phenol) in surgery and in taxidermy.

1866 John Langdon Haydon Down (Tor Point 1828 - 1896) publishes the description of "congenital idiots". He investigates what is now know as "Down's syndrome", due to triplication of all or part of chromosome 21 in man.

1866 Owen publishes On the Anatomy of Vertebrates.

1867 Kovalevsky extends the germ layer concept of Christian Heinrich Pander and von Baer to include the invertebrates, establishing an important embryologic unity in the animal kingdom.

1867 Johan Ludwig Wilhelm Thudichum (1829-1901) purifies hematin deprived of its iron atom (porphyrin).

1867 Theodore Meynert (1833-1898) under whom later Sigmund Freud learned brain anatomy, performs histological analysis of the cerebral cortex.

1868 Wilhelm Busch (?-Bonn ?) endeavours to treat cancer, unknowingly using bacteria. As a surgeon in Bonn, Germany, he attempts to treat a patient with inoperable neck sarcoma with erisypela (we now know that this condition is caused by Streptococcus pyogenes).

1868 Darwin elaborates the theory of pangenesis to explain cell differentiation and evolution and gives it its name.

1868 Etienne Jules Marey (1830 - 1904) publishes his lessons at the Collège de France: Du mouvement dans les fonctions de la vie, where he describes a new method to record movements. This starts his further studies at the Ecole Pratique des Hautes Etudes, where he was to invent methods at the origin of cinematographic recording.

1868 Helmholtz proposes the resonance theory of hearing.

1868 Joseph Arthur de Gobineau (1816 - 1882), surprising with his mixture of linguistic and penetrating biological views, states in his Mémoires sur diverses manifestations de la vie individuelle that «Après l'entozoaire spermatique, il y a la cellule, dernier terme jusqu'ici découvert à l'état génésiaque, et la cellule n'est pas moins le principe formateur du règne végétal que du règne animal.», thus spreading the cell theory in the domain of Art and Literature.

1868 Julius Bernstein (1839 - 1917), repeating von Helmoltz's velocity measurement, makes the hypothesis that a nerve impulse is a localized region of "depolarization," a "wave of negativity", due to the existence of a "transmembrane potential." He measures the time course of the action potential.

1868 Boussingault points out that plants require oxygen for photosynthesis.

1869 Johann Friedrich Miescher (Basel 1844 - 1895), discovers "nuclein" that is soluble in alkali but not in acids in the pus of wounds of soldiers of the war at Sebastopol. This substance came to be known as nucleic acid. Miescher later discovered that the amount of carbon dioxide in the blood affects the respiratory rate.

1869 Paul Langerhans (Berlin 1847 - Funchal 1888), later a Physician and an Anatomist, Professor of Pathological Anatomy in Freiburg publishes his doctoral thesis on the structure of the pancreas, where he notes specialized groups or islands of cells which produce insulin and glucagon and that are especially well supplied with microscopic blood vessels (Islets of Langerhans); he also describes the fundamental dendritic cells found in the epidermis of the skin (Cells of Langerhans) in a publication of the Beitrag zur mikroskopischen Anatomie der Bauchspeicheldruse.

1869 Jean Louis Rodolphe Agassiz (Motier 1807 - Cambridge (USA) 1873) exposes his views in De l'Espece et de la Classification en Zoologie, in which he attacks Darwin's approach to evolution (Chapter 7: Le Darwinisme).

1869 Francis Galton (Birmingham, 1822 - London 1911), cousin of Charles Darwin, claims that intelligence is inherited as a straightforward trait (publication of Hereditary Genius)

1870 Eduard Hitzig (1838 - 1907) and Gustav Fritsch (1839 – 1927) in their article "On the Electrical Excitability of the Cerebrum" explore the cortical motor area of the dog using electrical stimulation.

1870 Justus von Liebig (Darmstadt 1803 - München 1873) proposes that all fermentations are chemical reactions rather than vital processes. This will start a bitter controversy between Claude Bernard (who agrees with Liebig) and Pasteur (who thinks that life is needed for fermentation).

1870 Quatrefages publishes Charles Darwin et ses précurseurs français where he strongly attacks darwinism and maintains a theory of the Unity of Man.

1870 Wallace publishes his Contributions to the Theory of Natural Selection.

1870 Herbert Spencer (Derby, 1820 - 1903) publishes A System of Synthetic Philosophy, where he advocates darwinism in a form which distorts its premisses, stating that evolution proceeds through the "selection of the fittest". His positivist system, which is reminiscent of that of Auguste Comte, and tries to associate all sciences and philosophy together in a single picture, states that the unifying principle is evolution from a state of homogeneity to one of heterogeneity. The implicit underlying causality principle is of a definite Lamarckian flavour (there is, of course, no "fittest" whatever the environment...).

1870 Ernst von Bergmann (1836 - 1907) writes the first textbook on nervous system surgery.

1870 In 1863, Jean-Baptiste André Dumas (Alès 1800 - Cannes 1884), Pasteur's teacher, and a member of the Senate as well as a distinguished chemist, had requested that Pasteur leaves Paris for the south of France to study silkworm diseases. This resulted in the Étude sur la maladie des vers à soie in which Pasteur describes a method still in use today to prevent the disease, pébrine, caused by Microsporidia Nosema bombycis.

1871 Silas Weir Mitchell (Philadelphia 1829 - 1914) provides a detailed account of the phantom limb syndrome.

1871 Pasteur conclusively demonstrates that yeast is necessary for fermentation as it can be carried out in its presence only. He distinguishes two kinds of ferments, "organized ferments" such as yeast or lactic acid bacteria, and "unorganized ferments" like pepsin and amylase. This starts a violent debate with Edmond Frémy and Auguste Trécul.

1871 Louis-Antoine Ranvier (1835 - 1922) describes nerve fiber constriction ("nœuds de Ranvier")

1871 Lambert Adolphe Jacques Quételet (Gand 1796 - Bruxelles 1874), who had organized the first international statistics conference in 1853, shows the importance of statistical analysis in biology and sets the foundation of biometry. The Quetelet index is used to measure obesity.

1871 François Henri Hallopeau (Paris, 1842 - 1919) coins the word "antibiotique" to express the concept of substances opposed to the development of life. The word "antibiotic" existed in English with an entirely different meaning ("opposed to the belief of life in another place, e.g. extraterrestrial life"). The word was scantly used, until Waksman in 1941- 1942 used it to qualify the substances acting against microbes such as Penicillin.

1871 Publication of Charles Darwin's The Descent of Man and Selection in Relation to Sex, in which the role of sexual selection in evolution is described for the first time.

1872 Pierre Cyprien Oré (Bordeaux, 1828 - 1889) uses chloral hydrate as an intravenous anesthetic.

1872 Richard Dedekind (Brunswick 1831 - 1916)'s Stetigkeit un irrationale Zahlen establishes that there is a conceptual discontinuity between rational numbers and "real" numbers. This work is a landmark in the double view of mathematics as constructed from axioms or as the result of algorithms.

1872 Ferdinand Julius Cohn (Breslau [Wrocław] 1828 - Breslau 1898) in his Untersuchungen über Bacterien coins the term "bacterium" and founds the study of bacteriology.

1872 Karl Ludwig and Eduard Friedrich Wilhelm Pflüger (1829-1910) study the processes of gas exchange in the blood and show that oxidation occurs in the tissues rather than in the blood.

1872 Anton Dohrn (Stettin 1840 - 1909) founds the Stazione Zoologica in Napoli.

1872 Karl Joseph Eberth (1835-1927) shows that anthrax can be filtered from blood.

1872 George Huntington (1850-1916) describes the symptoms of a hereditary chorea ("danse de Saint-Guy").

1872 The British Navy corvette H.M.S. Challenger leaves from Portsmouth for an expedition that greatly extended our knowledge of the extent and variety of marine life (1872-1876). The expedition is directed by Scottish professor Charles Wyville Thompson (1830 - 1885) and naturalist John Murray (1841 - 1914), a Canadian.

1872 Lacaze-Duthiers creates the Roscoff marine biology laboratory which played a fundamental role in the institutionalization of marine biology in the last decades of the 19th century, thanks as well to the diffusion of the results realized with the publication of the Archives de zoologie expérimentale.

1873 Camillo Golgi (Corteno 1843 - 1926) publishes his first study on the potassium dichromate / silver nitrate method to stain cells ('la reazione nera").

1873 Charles Philippe Robin (1821 - 1885), the first tenured professor of the Histology chair at the Faculty of Medicine in Paris publishes an important Dictionnaire de Médecine, where he is still explicitely reluctant to accept the cell theory. He supposes that cells derive from an initial structure which is not cellular in nature.

1873 Marey publishes La machine animale, locomotion terrestre et aérienne, translated the following year into english (Animal mechanism: a treaty on terrestrial and aerial locomotion).

1873 Joseph Achille Le Bel (1847 - 1930) and Jacobus Henricus van't Hoff (Rotterdam 1852 - Steglitz 1911) independently invent the theory of asymmetric carbon, to account explicitely for the existence of stereoisomers, stemming from the foundation of stereochemistry pioneered by Louis Pasteur.

1873 Friedrich Anton Schneider (1831 - 1890) shows by adding acetic acid to fertilized eggs of the plathelmith Mesostomum ehrenbergii that nuclear filaments (chromosomes) move and change during cell division. His account is the first accurate description of the process of mitosis in animal cells, showing that the nucleus disappears and that it changes to a bulk of thin threads subsequently becoming thicker and differentiating along an axis through the cell.

1874 Vladimir Alekseyevich Betz (1831 - 1894) describes pyramidal cells in the primary motor cortex of the brain.

1874 Roberts Bartholow (1831 - 1904) in his Experimental investigations into the functions of the human brain describes how he could not resist to electrically stimulate human cortical tissue, and describes the outcome of the experiment.

1874 Carl Wernicke (Tarnowitz 1848 - Thüringer Wald 1904) publishes Der Aphasische Symptomencomplex on aphasias.

1874 Karl Ludwig Kahlbaum (1828 - 1899) describes a clinical form of early dementia, katatonie, (subsequently introduced in French and English in 1888: catatonie and katatonie)

1874 William Benjamin Carpenter (1813 - 1885) publishes his Principles of mental physiology : with their applications to the training and discipline of the mind, and the study of its morbid conditions where he proposes the "sensory ganglion" (thalamus) as seat of consciousness.

1874 Gull recognizes and describes the disease known as Gull's disease - myxoedema with the atrophy of the thyroid gland - which he regards correctly as the adult form of cretinism. He also describes anorexia.

1874 Wilhelm His (Basel 1831 - 1904) in Über unsere Körperform und das physiologische Problem ihrer Enstehung; Briefe an einen Befreundeten Naturforscher suggests mechanical explanations to account for morphological changes in the embryo.

1874 Albert Wigand (1812 - 1886) in Der Darwinismus strongly opposes Darwin's idea, trying to bring out the weaknesses underlying the theory of natural selection, and maintaining the existence of a definite course and plan in evolution.

1874 Haeckel establishes the taxonomic position of the Chordata, and proposes an hypothetical "Gastrea", similar to a first stage of embryo development, as the hypothetical ancestor to all metazoa.

1874 Gottlob Frege's (1848 - 1925) Die Grundlagen der Artithmetik. Eine logisch mathematische Untersuchung über den Begriff der Zahl is an elaborate attempt to characterize integers and link them to logic.

1874 Hughlings Jackson after the discovery of aphasia by Wernicke maintains in On the nature of the duality of the brain (Medical Press and Circular) that the right hemisphere has special functions.