Marcellin Berthelot

“{{Gutenberg author |id=Berthelot,+M.+(Marcellin) | name=Marcellin Berthelot}}”

“During the siege of Paris, Berthelot was President of the Scientific Committee of National Defence, and was occupied in the manufacture of explosives, and in 1883 he published, in two volumes, his work, Sur la Force des Matieres Explosives... a valuable contribution to the science...”

“Berthelot's agricultural station and laboratory were at {{w|Meudon}}, and here experiments on vegetable soils, the fixation of atmospheric nitrogen in soils by the agency of microbes, the action of electricity on the growth of plants, etc., were conducted. Berthelot states that twenty-five pounds of {{w|nitrogen}} per annum per acre might be fixed by bacteria.”

“His laws are... (1) The heat disengaged in any reaction is a measure of the chemical and physical work accomplished in the reaction. (2) The total thermal value of a reaction is dependent only on the initial and final states of the changing system. (3) "The Law of Maximum Work," or "the theorem of the necessity of reactions"... This law is the fundamental principle of Berthelot's thermo-chemistry: "The quantity of heat evolved in a reaction measures the sum of the physical and chemical changes which occur in that reaction"—"ce principe fournit la mesure des affinités chimiques."”

“In 1864 Berthelot began his great work on thermo-chemistry, and in 1879... published... Essai de Mécanique Chimique fondée sur la Thermo-chimie.”

“[O]f the numerous syntheses of Berthelot, or the building up of chemical compounds, many... were [previously] only obtained [naturally] through... life, either animal or vegetable.”

“He formed {{w|hydrocyanic acid}} by the action of the electric spark on a mixture of {{w|nitrogen}} and {{w|acetylene}}.”

“He also formed {{w|methane}} by passing the vapour of {{w|carbon disulphide}} and sulphuretted hydrogen over hot copper; and by the action of carbon monoxide on a hot solution of caustic potash, {{w|potassium formate}} was produced, the formate yielding {{w|formic acid}} on distillation with {{w|hydrochloric acid}}.”

“His methods were simple and direct. By means of the electric spark, {{w|carbon}} and {{w|hydrogen}} united to form {{w|acetylene}}; or [acetylene was also obtained] by... [sparking] a mixture of hydrogen and {{w|carbon monoxide}}...or by... spark[ing] a mixture of hydrogen with {{w|carbon disulphide}} vapour, or {{w|cyanogen}}.”

“In 1860 Berthelot's Chimie Organique fondée sur la Synthèse, was published. It was the first... based entirely on synthesis.”

“Although glycerine was discovered by Scheele in 1779, and its formula established by Pelouze in 1836, it was not until 1854 that its true composition was known... [when] Berthelot... proved that it is an alcoholic compound capable of interacting with... acids as acetic and palmitic.”

“Berthelot was quite sure that physics and chemistry would soon solve the problem of aerial navigation, and he significantly remarked that when they do so " customhouses will fall of themselves."”

“Berthelot was justified by accomplished facts in stating that applied science has done more for mankind in the last three-quarters of a century than all the progress in all ages that preceded it.”

“Berthelot believed in the possibility of wheat-growing and cattle-raising being superseded by the discovery of artificial substitutes for the necessaries of life. ...Berthelot's idea of the synthesis of substances that will take the place of wheat and meat is the most audacious flight of fancy... but it need not... be classed among the impossibilities.”

“The first half of the nineteenth century was devoted to analytical chemistry—this being due to the great work of Berzelius. The second half, however, was the era of Berthelot or synthetical chemistry.”

“His scientific labours were immense, and he completely revolutionized chemistry in more departments than one. He transformed agriculture; proved that inorganic and organic bodies obey the same laws; established "la théorie des affinités"; and invented thermo-chemistry.”

“Probably the most important syntheses of his are the production of acetylene from carbon and hydrogen, and methane or marsh gas, by means of the well-known Berthelot's reaction; and of dynamical chemistry, his most important discovery is "the law of maximum work."”

“[H]e was not only a great chemist, but a politician, philosopher, and author.”

“Although Wohler, in 1828, produced {{w|urea}} artificially, and Kolbe synthetized {{w|acetic acid}} in 1845, Berthelot was undoubtedly the creator or founder of organic synthesis.”

“He produced over a thousand memoirs, embracing every department of chemistry.”