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245 BCE
Archimedes Writes "On Floating Bodies"
Archimedes made many contributions to science, especially to early hydrodynamics. His work, "On Floating Bodies," is the earliest known formulation of the buoyant force: a body submerged in a liquid has a force equal to the weight of the liquid it displaces applied to it from below. https://www.britannica.com/science/Archimedes-principle -
Period: 1486 to 1505
Da Vinci's Contributions Fluid Dynamics
Leonardo Da Vinci performed many experiments involving fluids, and theorized about the flow of blood in the human body. He was particularly interested in the heart, and later on vortex theory would vindicate his hypothesis on its functionality. https://www.nature.com/articles/d41586-019-02144-z -
Period: 1487 to 1505
Da Vinci Notes Inconsistencies in the Dominant Geological Theory
Da Vinci noted in his journals that the fossils of clams in mountains of Italy could not have been deposited by the flood described in Genesis. He believed in a gradual explanation of geography. (Da Vinci's Journals, page 987) -
1570
Abraham Ortelius Publishes "Theater of the World"
Abraham Ortelius publishes Theatrum Orbis Terrarum (Theater of the World), the first modern atlas. He proposes in the later 1597 edition that South America and Africa may have been unified in the past, and torn asunder. (Theater of the World) -
Newton's Contributions to Hydrodynamics
Isaac Newton was the first person to mathematically formalize viscosity, the internal friction of liquids. His equation involved shear stress, which is the force acting parallel to a plane, which in liquids causes layers to move over each other. https://processfluiddynamics.wordpress.com/newtons-law-of-viscosity/ https://www.resolvedanalytics.com/the-greats-of-fluid-dynamics/isaac-newton-fluid-dynamics -
Daniel Bernoulli Publishes Hydrodynamica
Daniel Bernoulli worked on a lot of different things in his lifetime. He had a doctorate in medicine, which he completed by applying the conservation of energy to the breath. His background in medicine, specifically the lungs and the blood, are thought to have contributed to his interest in fluids.
Bernoulli's principle, the main takeaway from Hydrodynamica, states that the speed of a fluid is inverse to pressure and elevation. https://mathshistory.st-andrews.ac.uk/Biographies/Bernoulli_Daniel/ -
Jean le Rond d'Alembert Publishes Treatise on the Equilibrium and Motion of Fluids
Just a few years after Bernoulli’s Hydrodynamica, d'Alembert published (Treatise on the equilibrium and motion of fluids).
It builds off of the d'Alembert principle, which was first proposed by Jacques Bernoulli in 1708 but was a major focus of d'Alembert’s in the years leading up to this Treatise. d'Alembert’s principle states that a body can be treated as static, even if it’s moving, so long as its inertial force is equal to the force keeping it in motion.
Resolved Analytics: d'Alembert -
Lilienthal Proposes that the Continents were Once Unified
Theologian Theodor Christoph Lilienthal used Genesis 10:25 (reading “Two sons were born to Eber: One was named Peleg [meaning division], because in his time the earth was divided; his brother was named Joktan.") as evidence to support his proposal that the continents were unified in the past. This was more accepted than Ortelius's proposal, but only just. (A historical account of how continental drift and plate tectonics provided the framework for our current understanding of palaeogeography) -
Herman von Helmholtz's Contribution
Herman von Helmholtz, a very prominent natural philosopher, publishes (On integrals of the hydrodynamic equations corresponding to vortex motions). In it, he describes the motion of fluid particles in a vortex, which is a region where fluid flows around an axis. He is more famous for other work, including proof of non-Euclidian geometry. https://plato.stanford.edu/entries/hermann-helmholtz/#AcouElecFluiDyna1855 -
Period: to
Eduard Suess Publishes "The Face of the Earth"
Eduard Suess published his 4-volume treatise on geology, Das Antlitz der Erde (The Face of the Earth). This became the definitive text on geology for many years, and made the gradual view of geological change the definitive view. (The Face of the Earth) -
Osbourne Reynolds Publishes "On the dynamical theory of incompressible viscous fluids and the determination of the criterion"
Reynolds created/discovered the "Reynolds number," which is used to differentiate between a laminar and turbulent flow. A laminar flow is streamlined and predictable, and a turbulent one is not. https://personalpages.manchester.ac.uk/staff/jdjackson/Osborne%20Reynolds/oreyna.htm -
Alfred Wegener Publishes "The Origin of Continents and Oceans"
Alfred Wegener, a German meteorologist, became fascinated with the parallels between South America and Africa's coastlines during an expedition in Greenland. This led him to study geology, and eventual disagreement with the accepted contraction theory of geology. Wegener proposed "drift theory," in which the continents were mobile plates drifting atop the mantle. He thought that this theory better explained the geological phenomena that were observed. (The Origin of Continents and Oceans) -
Arthur Holmes Proposes Mantle Convection
Prominent geologist Arthur Holmes proposed that magma in the mantle would cool as it approached the surface, causing it to sink and be reheated near the core, which would cause it to rise and repeat the process, creating convection currents. -
Harry Hess Publishes "History of Ocean Basins"
Harry Hess, president of the Geological Society of America, publishes "History of Ocean Basins," in which he combines Holmes's model of drift theory with knowledge of mid-ocean ridges. Hess proposed that the crust is made of plates that include both continental and oceanic crust, and that the plates recycled rock back into the mantle. This was the first theory that adequately explained the lack of pre-Mesozoic rock in the oceanic crust. (History of Ocean Basins)