Works of Louis Pasteur (English)

Investigation into the role attributed to atmospheric oxygen gas in the destruction of animal and vegetable substances after death

Louis Pasteur in his laboratory

The most ordinary observation has at all times demonstrated that animal and vegetable substances, exposed after death to contact with atmospheric air, or buried in the earth, disappear, in consequence of various transformations. Fermentation, putrefaction, and slow combustion, are the three phenomena which concur in the accomplishment of this great fact of the destruction of organic substances–a condition necessary for …

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The Attenuation of the Causal Agent of Fowl Cholera

Pasteur conducting germ theory experiment in his laboratory

Originally published by Louis Pasteur in 1880 I would like to reiterate the following results, which I have previously had the honor of presenting to the academy: Fowl cholera is a virulent disease of the first order. The virus* consists of a microscopic parasite which multiplies readily in culture away from the animal body. From this it is possible to …

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Louis Pasteur: Infusorian Animalcules Living Without Free Oxygen

Lactic Acid - Microscopic beer samples

Comptes rendus de l’Académie des sciences 52 (February 25, 1861): 344-47; Reprinted in Oeuvres de Pasteur, vol. 2, pp. 136-38. Translation by A.S. Weber. The variety of products formed by the so-called lactic fermentation are well known. Lactic acid, a gum, mannite, butyric acid, alcohol, carbonic acid and hydrogen appear simultaneously or successively in extremely variable and quite unexpected proportions. …

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Open Letter to Robert Koch

Louis Pasteur sitting at table

Translated by Pierre Beaudry Pasteur, Louis. Correspondance : 1840-1895 / de Pasteur. Tome III / réunie Open letter to Robert Koch, December 25, 1882. Sir, In 1881, you have attacked my works too quickly and without due consideration, in your first volume of the German Imperial Health Office published, in Geneva on September 5, 1882, and, meanwhile, I have refuted …

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Experiments and New Views on the Nature of Fermentations

Yeast under the microscope

Comptes Rendus 52, 1260 (1861) [as translated and excerpted in Mikulás Teich, A Documentary History of Biochemistry, 1770-1940 (Rutherford, NJ: Fairleigh Dickinson University Press, 1992)] … It results from this that beer yeast has two ways of living, essentially distinct. Free oxygen gas can be totally absent, or it can be present in any volume whatever. In the second case …

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Studies on Fermentation by Louis Pasteur

Download PDF AUTHOR’S PREFACE. Our misfortunes inspired me with the idea of these researches. I undertook them immediately after the war of 1870, and have since continued them without interruption, with the determination of perfecting them, and thereby benefiting a branch of industry wherein we are undoubtedly surpassed by Germany. I am convinced that I have found a precise, practical …

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Louis Pasteur: Germ Theory And Its Applications To Medicine And Surgery

Translation: H.C.Ernst, Germ Theory And Its Applications To Medicine And Surgery 1 The Sciences gain by mutual support. When, as the result of my first communications on the fermentations in 1857-1858, it appeared that the ferments, properly so-called, are living beings, that the germs of microscopic organisms abound in the surface of all objects, in the air and in water; …

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Reflections On My Life by Louis Pasteur

There is a time in every man’s life when he looks to his God, when he looks at his life, when he wonders how he will be remembered. It can happen with age or with tragedy or closeness of death. I am lying here at age 45, not able to feel my left side. Not knowing if this stroke that …

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On the Extension of the Germ Theory to the Etiology of Certain Common Diseases

[Footnote: Read before the French Academy of Sciences, May 3, 1880. Published in Comptes rendus, de l’Academie des Sciences, xc., pp. 1033-44.] When I began the studies now occupying my attention, [Footnote: In 1880. Especially engaged in the study of chicken cholera and the attenuation of virulence–Translator.] I was attempting to extend the germ theory to certain common diseases. I …

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Physiological Theory of Fermentation by Louis Pasteur

Modern History Sourcebook: Louis Pasteur (1822-1895): Physiological Theory of Fermentation, 1879 Table of Contents Author’s Preface – Preface Section I – On the Relations Existing Between Oxygen and Yeast Part I Part II Section II – Fermentation in Saccharine Fruits Immersed in Carbonic Acid Gas Section III – Reply to Certain Critical Observations of the German Naturalists, Oscar Brefeld and …

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