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	In 1651, Harvey published the concept that all living things originate from eggs.  Harvey believed that in principle organisms could be spontaneously generated, and that the process was the self-generation of a complicated machine.
	In 1651, Thomas Hobbes, in Leviathan, argued from a mechanistic theory that man is a selfishly individualistic animal at constant war with others.  In the state of nature, life is "nasty, brutish, and short."
	In 1652, Thomas Bartholin discovered the lymphatic system and determined its relation to the circulatory system.
	In 1654, Otto von Guericke removed the air from within two metal hemispheres.  Teams of horsemen were challenged to pull them apart, which they failed to do.
	[In 1654, James Ussher, Protestant archbishop of Armagh, determined by a close reading of scriptural genealogies that the events described on the first page of the Book of Genesis occurred in 4004 B.C.]
	In 1654, William Petty, working on Irish estates confiscated by Oliver Cromwell, carried out the first large scale attempt at a scientific survey.
	In 1655, Christiaan Huygens discovered 'Titan,' Saturn's largest moon, and that what Galileo had thought were moons were actually rings.  He was the first to note markings on Mars.  He also applied Galileo's idea that a falling body does so in a straight line to planetary orbits, calculating "the radial force necessary to keep a planet in a circular path [is] mv2/r, where m is the mass, v the velocity, and r the orbital radius" (Grosser 1979:9).
	In the mid-1650s, Thomas Sydenham promoted the idea that diseases were organisms inside a host.  He advocated direct observation and classification to determine the nature of disease, and introduced quinine and laudanum to English medicine.
	In 1656, John Wallis, in Opera mathematica, made the transition from the geometry of lines to the arithmetic of numbers where he made the first use of the category 'infinity' in the field of arithmetic and invented its symbol.
	In 1656, Huygens built the first pendulum-regulated clock.  Two years later, Huygens, in Horologium, claimed that his clock could establish longitude at sea which was not then possible and had led to many maritime disasters.  This claim was not borne out.
	In 1657, Fermat stated the 'least time' principle according to which a light ray follows the path to its destination in the shortest possible time.
	In 1657, Huygens wrote the first textbook on probability, Calculating in Games of Chance.
	In 1658, Henry More, in Immortality of the Soul, argued "the first primary matter must be atoms and that matter may be so small as to be indiscernible" (Newton, quoted in White 1997:55).
	In 1659, Pascal, in Traité des sinus du quart de cercle, used the language of infinitesimals when writing of the sum of all the ordinates.  In De l'esprit géometric, he held that in numbers the infinitely large and the infinitely small are complementary.
	In 1661, Marcello Malpighi, in De pulmonibus, reported his observation of blood movement through the capillaries.  He is also noted for his studies of the glands.
	In 1661, Robert Boyle, in the Sceptical Chymist, separated chemistry as corpuscles, from alchemy, as qualities, and gave the first precise definitions of a chemical element, a chemical reaction, chemical analysis, and made studies of acids and bases. It was only after this that scientists generally abandoned the ancient notion that matter was compounded of 'Fire, Earth, Air, and Water.'
	In 1662, Boyle, using a vacuum pump of his own invention, determined that the volume and pressure of a gas are inversely proportional.  This is known as 'Boyle's law.' He also determined that sound doesn't travel in a vacuum.
	In 1662, Antoine Arnauld and others contributed to a book known as the Port Royal Logic, or the Art of Thinking, where the question was first taken up of the two sorts of non-deductive reasoning, inference and decision under uncertainty, on the one hand, and theorizing, or what Charles Sanders Peirce later called 'abduction,' on the other.
	Beginning in 1662, Isaac Barrow lectured on geometry.  The results of his investigations include many theorems on tangents and quadratures and an atomistic conception of a line: "Time has many analogies with a line...; for time has length alone, is similar in all its parts, and can be looked upon as constituted from a simple addition of successive instants or as a continuous flow of one instant" (Barrow 1662:37).  All of his propositions were cast in geometric forms which Newton, his student, recast in the analytic symbolism of Fermat, Descartes, and Wallis.
	In 1662, John Graunt, in Observations upon the Bills of Mortality, using London population data, noted that life expectancy is 27 years, with nearly two/thirds dying before 16 years.
	In 1663, James Gregory, in Optica Promota, described the reflecting telescope which he had built and which used a convergent mirror as its object in order to cure aberrations.
	In 1664, Thomas Willis, in Cerebri anatome, identified the corpus striatum, now called the basal ganglia, as the initiator of motor acts as well as being the receiver of sensory data. and distinguished the cortical gray matter from the deeper white matter. He also abandoned Galen's doctrine of the ventricles and gave primacy to the cerebral cortex.  [revised 02/01/03]
	In 1665, Francesco Maria Grimaldi, in Physico-Mathesis de lumine, coloribus, et eride, published posthumously, discovered that light going through a fine slit cannot be prevented from spreading on the farther side, a phenomena which he named 'diffraction' and postulated was caused by its wave-like motion.
	In 1665, Robert Hooke, in Micrographia, named and gave the first description of cells. He also described plant and animal fossils, comparing their microscopic structure to that of living organisms. Hooke also noted the 'black spot' in soap bubbles, and, independently of Grimaldi, hypothesized that light is "a 'very short vibrative motion' transverse to straight lines of propagation through a 'homogenous medium.'  Heat [is] defined as 'a property of a body arising from the motion or agitation of its parts'" (Koyré 1965:223n2).
	In 1665, Gian Domenico Cassini, while attempting to map Jupiter, discovered the Great Red Spot, an area about 48,000 by 11,000 kilometers that drifts across the planet's south temperate zone.
	By 1666, Newton had discovered the essentials of calculus, the law of universal gravitation, and that white light is composed of all the colors of the spectrum.
	In 1668, Francisco Redi described a series of experiments which showed that the maggots in meat were the larva of flies.
	In 1668, Cassini published an ephemerides of great accuracy and included the rotational periods of Jupiter, Mars, and Venus.  This won him the directorship of the Paris observatory the following year where both Huygens and Olaus Roemer worked under him.
	In 1669, Newton circulated a manuscript, De analysi per aequationes numero terminorum infinitas, the first notice of his calculus, which gave "a generally applicable procedure for determining an instantaneous rate of change and to invert this in the case of problems involving summations" (Boyer 1949:192).  A more extensive exposition of the calculus, Methodus fluxionum et serierum infinitarum, with the introduction of his characteristic terminology, was available in manuscript about two years later.  The former was not published until 1711; the latter, 1736.
	In 1669, Nils Steensen, known as Steno, by postulating a sequence of distinct geological phases, was able to explain how land acquired its current conformation: E.g., marine fossils indicate a former sea bed, which was violently uplifted, and, afterward, undermined by subterranean forces, causing the strata to breakup, become eroded, and, in due course, form another sea bed.
	In 1670, Boyle produced hydrogen by reacting metals with acid.
	In 1670, the editors of the Port Royal Logic published Pascal's Pensées, eight years after his death.  In it, he discusses probabilty in terms of a wager on the existence of God: If God exists, wagering that he doesn't brings damnation and that he does brings salvation.  Since salvation is better than damnation, 'God exists' dominates the wager.
	Between 1671 and 1684, Cassini discovered four of Saturn's moons and studied the division in its ring system that bears his name.  Also, in 1671, he made the first successful measurement of the parallax of Mars in an effort in which Jean Richer led an expedition to Guiana in order to create a base sufficient for the triangulation.
	In 1672, More, in Enchiridium metaphysicum, asserts "the real existence of infinite void space...as a real precondition of all possible existence [and] as the best and most evident example of non-material--and therefore spiritual--reality and thus the first and foremost...subject-matter of metaphysics" (Koyré 1957:137).  More had taught Newton in his first years at Cambridge ten years earlier
	About 1674, Hennig Brand discovered phosphorus in a distillation of human urine.
	In 1674, Nicolas Malebranche elaborated the conception that each embryo is encased in the embryo of its parent.
	In 1674, Anton van Leeuwenhoek reported his discovery of protozoa. [added 02/01/03]
	In 1675, Nicolas Lémery published a chemistry textbook in which he espoused the corpuscle theory.
	In 1676, Nehemiah Grew suggested the true nature of ovules and pollen.
	In 1676, Roemer proved that light travels at a finite speed by repeated observations of eclipses of Jupiter's moon, Io. The period of the orbits of Jupiter's moons had previously been perceived to vary, but Roemer pointed out that it is the Earth's movement plus light's constant speed which create this appearance, that is, what we would call a 'Doppler effect.'
	In 1677, Guillaume Lamy, in Explication mécanique et physique des fonctions de l'âme sensitive, used the words soul and animal spirits without differentiation: "J'ay pris indifféremment les mots d'âme et d'esprits, ce qui ne doit point faire de confusion, car c'est la mesme chose"(Lamy 1677:176). [added 02/01/03]
	In 1678, Huygens, in a communication to the Academie des Science, propounded a wave theory of light propagated through 'aether,' and held that every point on a wave is itself a source of new waves.  At the same time, he reported his discovery of the double refraction of light when viewed in calcite.  This theory was published in 1690 as Traité de la lumière.
	In 1678, Edmond Halley returned from St. Helena where he had added 341 stars to the southern hemisphere catalogue with the aid of a telescope.  After observing a transit of Mercury across the Sun, he recognized the possibility of using Venus's transit of the Sun--known to occur in 1761--for determining the distance of the Sun by measuring solar parallax.
	In 1679, Giovanni Alfonso Borelli, in De motu animalium, interpreted the locomotory apparatus of vertebrates from a strictly mechanical point of view.  In a study of disease, he concluded that something entered the body which could be remedied chemically.
	In 1679, Denis Papin devised a vessel in which the boiling point of water is raised by an increase in steam pressure.  This demonstrated the influence of atmospheric pressure on boiling points.
	In 1682, John Ray described empirically 18,000 species of plant.
	By 1683, Anton van Leeuwenhoek, with microscopes, some of which magnified 270 times, had seen red blood cells, sperm cells, and almost all classes of microorganism known today.  He hypothesized that these were carried in the air, not spontaneously generated.  Also, van Leeuwenhoek was able to faithfully describe the nervous system and was the first to describe the life cycle of an ant, from egg to larva to pupa to adult. [added 02/01/03]
	In 1684, Gottfried Wilhelm von Leibniz published his system of calculus, developed independently of Newton.  It is Leibniz's notation which has been adopted.  He also invented a scheme for a logical syntax which he called the 'Universal Characteristic' and which "was supposed to enable us to compute the probabilities of disputed hypotheses relative to the available data" (Hacking 1975:140).
	In 1687, Newton published Philosophiae naturalis principia mathematica, a summary of his discoveries in terrestial and celestial mechanics in which he makes continual use of Euclidean theorems and constructions, and the first published account of his calculus.  In contrast to Kepler, he did not explain the features of the solar system by deducing them from a purpose.  In contrast to Descartes, he carefully preserved the distinction between mathematical descriptions and theories about matter and causation.  For example, writing of gravitational attraction, he said that "our purpose is only to trace out the quantity and properties of this force from this phenomena, and to apply what we may discover in some simple cases [e.g., the moon] as principles by which, in a mathematical way, we may estimate the effects thereof in more involved cases [e.g., the planets]"....  Absolute, true, and mathematical time, of itself, and from its own nature, flows equably without relation to anything external, and by another name is called duration (Newton 1729:550).  The first part of the Principia concerns dynamics and includes his laws of motion, the second concerns fluid motion, and the third, the mechanical unity of his principle of gravitational attraction in relation to the 'centripetal force' of the planet's motion, that is, Kepler's laws of planatary motion. "Newtonian mechanics [may be] understood as the combination of two laws: the law of motion, according to which force is equal to mass times acceleration; and the law of universal gravitation, according to which the force of attraction between two bodies is proportional to the product of their masses and inversely proportional to the square of the distance separating them" (Sokal and Bricmont 1998:64).  "In opposition to the pre-Galilean and pre-Cartesian conception, which understood motion as a species of becoming..., the new, or classical, interpretation interprets motion as a kind of being, that is, not as a process, but as a status, a status that is just as permanent...as rest" (Koyré 1965:9). Holding that the Earth's rotation, its motion, is relative to absolute space, Newton finds it necessary to distinguish "time, space, place, and motion...into absolute and relative, true and apparent, mathematical and common.  [E.g.,] absolute space, in its own nature, without relation to anything external, remains always similar and immovable"....  Absolute, true, and mathematical time, of itself, and from its own nature, flows equably without relation to anything external, and by another name is called duration (Newton 1729:6).
	At the same time, Newton wished to demonstrate that the world which obeyed these laws was compatible with the sort of atoms which he imagined, atoms which were aethereal forces as everything else.  These forces counted among their number, at a minimum, inertia and gravity, which are proportional to each other, cohesion, or the mutual attraction and repulsion that the particles have for each other, and fermentation, and were, so Newton believed, "capable of holding identical particles in a sufficient variety of patterns to explain all the manifold diversity of Nature" (Thackray 1970:15).  Between the gravitating bodies are particles of a rarified medium, or aether, which are the repelling force.  Similar particles also account for the force which deflects the light through a prism (Cantor and Hodge 1981:1-2).  In addition, these forces were also capable of alchemical transmutation, i.e., "every body can be transformed into a body of another kind, and can take on all the intermediate grades of qualities" (Newton, quoted in Koyre 1965:14).  This, from the first edition, was modified in the 1713 edition and that modified in the 1729 edition, reflecting shifts in Newton's thought.
	In other words, there are two trends: The panmathematism of Galileo and Descartes and the empirical, experimental 'corpuscular philosophy' of Gassendi, Roberval, Boyle, and Hooke. "From this perspective...Newton presents us with a synthesis of both trends, of both views" (Ibid.:12). As for Newton's particles vis à vis Huygens' waves, it was not understood until the nineteenth century that these conceptions were not contradictory but complementary.
	In 1690, Papin invented a pump with a piston raised by steam.
	In 1690, John Locke, in Essay Concerning Human Understanding, repudiated the traditional notion of innate ideas and described the mind at birth as a tabula rasa, or blank slate, upon which the world describes itself through the experience of the five senses.  He also dealt with the probability of inferences.  In the same year, he published Two Essays on Civil Government, in which he maintained that it is the nature of man to be good, the state is formed by a social contract, and each man has the right to the product of his own labor.
	About 1692, Newton wrote De Natura Acidorum in which he set up a hierarchy from irreducible particles to particles of the first and second composition, and claimed that "if the particles of the first, or perhaps of the second composition of gold could be separated, that metal might be made to become fluid, or at least more soft.  And if gold could be brought once to ferment and putrefie, it might turn into any other body whatsoever" (Newton, quoted in Thackray 1970:24).
	In 1693, Ray, in Synopsis of Quadripeds and Snakes, disproved Descartes' claim that animals are unconscious.
	In 1693, Edmund Halley discovered the formula for the focus of a lens: If o is the distance of the object from the lens, i is the distance of the image, and f is the distance of the focus, then 1/o + 1/i = 1/f.
	In 1694, Rudolph Jakob Camerarious, in De Sexu Plantarum Epistola, reported the existence of sex in flowering plants.
	In 1698, Thomas Savery patented an engine which produced a vacuum by condensing steam.  It was employed for raising water from a mine and supplying water to several country houses.
	In 1704, Newton, in Opticks, presented his discoveries using light and elaborated his theory that it was composed of particles.  These particles, he assumed, were composed of uniform matter and space but of varying density depending on the amount of space between the particles. Writing of Huygens work with calcite where light has 'sides,' Newton found "an analogy between the two sides of the light beam and the two ends of a magnet that constitute its poles [and called] this property polarized light" (Fisher 2001:362).  He also inferred from the cohesion of "homogeneal hard Bodies...that their Particles attract one another by some force which in immediate contact is exceedingly strong" (Newton 1730:388-389).
	In 1704, Johann Sebastian Bach began composing music--music which was related to the musical consequences of the Pythagorean-Platonic proportional number systems, i.e., "the creation of the universe according to...the Timaeus, the best exposition of the numerical world-order Bach intended to depict" (Humphreys 1983:30-13).  This was the same year in which Newton, in Opticks, chose to add 'indico' to the spectrum of violet-blue-green-yellow-orange-red because "he wants the colors to correspond to the seven notes of the [Pythagorean] music scale" (Park 1990:264).
	In 1705, Halley, in Synopsis of Cometary Astronomy, observed that the comet which had appeared in 1682 was the reappearance of comets which had appeared in 1531 and 1607 and predicted its reappearance in 1758.
	In 1708, Hermann Boerhaave, in Institutiones Medicinae, recommended the Hippocratic method of bedside instruction and post-mortem examination where, for example, the relation between lesions and symptoms could be studied.
	In 1709, Gabriel Daniel Fahrenheit constructed an alcohol thermometer and, five years later, a mercury thermometer.
	In 1710, Jean Bernoulli pointed out that Newton had not proved Kepler's law of ellipses but only its converse and did so himself using calculus, solving "the general problem by reducing it to the same integral that is used to solve it today" (Park 1990:416).
	In 1710, George Berkeley, in Principles of Human Knowledge, attacked Newton's notion of 'absolute space.'  He believed that qualities, not things, are perceived and that perception is relative to the perceiver.
	In 1713, Newton, in a new edition of Principia, introduced the electric effluvium or aether as a "subtle, all-pervasive spirit, by whose 'force and action' material particles 'attract one another at near distances..., as well repelling as attracting the neighboring corpuscles' " (Newton, quoted in Heilbron 1979:239).
	In 1713, Jakob Bernoulli, in Ars conjectandi, expounded the theorem that, in an increasing number of binary trials, an increasing proportion of the total probability is concentrated in the neighborhood of the original probability of success in a single trial.  Bernoulli's theorem forms today the simplest case of the Laws of Large Numbers.
	In 1714, Leibniz, in Monadology, said that the Universe's ultimate constituents are 'monads,' simple substances, each of which perceives the Universe from a different point of view.  Their perceptions are harmonius, and what is needed, he said, is a mathematics which will demonstrate the universality of the relations between these points of view.
	[In 1714, the British parliament set up the Board of Longitude, consisting of scientists, naval officers, and government officials, which was "perhaps the world's first research and development agency" (Sobel 1995:54).  The Board was empowered to make financial awards in pursuit of a means to determine longitude at sea.  The two competing methods were astronomical calculation, which meant plotting the position of the moon against known stars, and by chronometer, which meant timing the position against a known land longitude.]
	In 1715, Thomas Fairchild produced the first artificial hybrid plant.
	In 1715 and 1716, Leibniz corresponded with Samuel Clarke to whom he strongly criticized the philosophy and the theological implications of Newton's work.  "The parts of space are not determined and distinguished, but by the things which are in it;" "instants, considered without things, are nothing at all" (Clarke 1717:78, 27).  In other words, Leibniz sees space and time as orders of coexistent and successive phenomena, not real substances but rather relations.
	In 1717, Jean Bernoulli propounded the 'Principle of Virtual Displacements: "Any time there is a state of equilibrium of given forces..., then, the sum of the positive energies will be equal to the sum of the negative energies taken positively" (Bernoulli, quoted in Duhem 1905:432).
	In 1718, Louis Joblot demonstrated that the microorganisms observed in solutions were the result of being brought in from the ambient air, which confirmed van Leeuwenhoek's conclusion.
	Beginning in 1718, Mary Wortley Montagu publicized the use of inoculation against smallpox in Turkey.
	In 1718, Halley said that stars move, i.e., they are not fixed to a single framework, since they had changed position since Ptolemy's Almagest.
	In 1718, Abraham de Moivre, in Doctrine of Chances, said chance can neither be defined nor understood, but probabilities could be calculated.
	In 1720, Wilhelm Jacob van 'sGravesande began the publication of the first modern survey of physics, Physices elementa mathimatica experimentis confirmata, sive introductio ad philosophiam newtonianam, in which he took physics to be a branch of mathematics.  Of electricity he said that it is that "Property of Bodies by which they attract, and repel lighter Bodies at a sensible distance" ('sGravesande, quoted in Heilbron 1979:241).
	In 1725, John Flamsteed completed the Historia coelestis Brittannica, a star catalogue far more accurate than its predecessors.
	In 1725, Giovanni Battista Vico, in Principi di Scienza Nuova, maintained that history is a man-made account of societies and their institutions.
	In 1727, George Graham and Anders Celcius, independently, determined that a disturbance on the sun was a magnetic storm.
	In 1727, Stephen Hales studied the ascent of water in plants and applied physical principles to the study of plant physiology.
	In 1728, Pierre Fauchard, in The Surgeon Dentist, described preventive measures to keep teeth healthy as well as inventing the word 'dentist.'
	In 1729, Stephen Gray discovered electrical induction, which he called 'communication,' and announced it in 1732.  He also distinquished between conductors and insulators (Heilbron 1979:245-249).
	In 1729, James Bradley announced his discovery of the aberration of starlight, which is occasioned through the joint effect of the Earth's motion and the non-instantaneous transmission of light.  His efforts to gauge the distance to the stars provided the first concrete evidence that the Earth moves through space and also the true value of the speed of light, improving on Roemer's estimate.
	In 1730, George Brandt discovered cobalt.
	In 1730, Charles François de Cisternay Dufay found that "almost everything except metals and very hard gems could be made phosphorescent" (Heilbron 1979:251).
	In 1731, John Hadley and, independently, Thomas Godfrey built reflecting quadrants by which the elevation of two celestial bodies and the distance between them could be measured at sea.  This instrument, by adding a telescope and a wider measuring arc, quickly evolved into the sextant.
	In 1733, Hales measured blood pressure.
	In 1733, Chester More Hall built an achromatic compound lens using glasses with different refractive indexes.
	Beginning in 1733, Dufay, in Mémoires sur l'électricité, summarized and generalized what was known about electricity: E.g., that all materials, except metals and those too soft to rub, can acquire electricity and all materials, especially metals, can "display the virtue after contact with an excited electric" (Heilbron 1979:252).  This latter principle became known as 'Dufay's rule.' ' He made discoveries, e.g., "objects with dissimilar electrifications attract, those with like electrifications repel," but his explanations were transient (ibid.:254-260).
	In 1733, John Kay patented the flying shuttle loom. [added 02/01/03]
	In 1734, David Hume, in A Treatise on Human Understanding, described 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" (Hume 1738:30).
	In 1736, Leonhard Euler, in Mechanica, solved the Königsberg Bridge Problem, that is, whether it were possible to perambulate the seven bridges of Königsberg without retracing one's steps.  He did so by means of the first graph theoretic model ever published.  His theorem is this: To be traversable every pair of points, or in this case land areas, can reach each other, and the number of lines, or bridges, is even.
	In 1736, John Harrison finished building and tested at sea what proved to be the first accurate chronometer for timing longitude.
	[By 1737, fifty years after the publication of Newton's Principia mathematica, the opposition to Newtonism had crumbled away.  "The uncommon incomprehensibility became a common incomprehensibility," as Ernst Mach expressed it (Mach, quoted in Koyré 1965:17).  The real world is no longer "conceived as a finite and hierarchically ordered...whole, but as an open, indefinite, and even infinite universe, united not in its immanent structure but only by the identity of its fundamental contents and laws...; a universe in which...astronomy and physics became interdependent and united because of their common subjection to geometry.  This, in turn, implies the disappearance...from scientific thought of all considerations based on value, perfection, harmony, meaning, and aim" (ibid.:7).  "The Newtonian law of attraction...is not only the only law of that kind that explains the facts but, besides, is the only one that can be uniformly and universally applied to large and small bodies, to apples and to the moon.  It is the only one, therefore, that it was reasonable for God to have adopted as a law of creation" (ibid.:15).  "If order and harmony so obviously prevailed in the world of nature, why was it that, as obviously, they were lacking in the world of man?  The answer seemed clear: disorder and disharmony were man-made....  The remedy seemed clear too: let us go back to nature, to our own nature, and live and act according to its laws....  So strong was the belief in 'nature,' so overwhelming the prestige of the Newtonian (or pseudo-Newtonian) pattern of order arising automatically from interaction of isolated and self-contained atoms, that nobody dared to doubt that order and harmony would in some way be produced by human atoms acting according to their nature, whatever that might be--instinct for play and pleasure (Diderot) or pursuit of selfish gain (A. Smith)" (ibid.:22).]
	In 1738, Daniel Bernoulli, in Hydrodynamica, asserted the principle that as the speed of a moving fluid increases, the pressure within the fluid decreases.In the process of determining this, he invented the 'molecular theory of gases,' now known as the 'kinetic theory of gases,' which introduced the notion that the gas particles were moving around rapidly, colliding and rebounding according to the laws of elementary mechanics; i.e., a gas's temperature is a function of the average speed of its particles.
	In 1738, François Marie Arouet de Voltaire, in Éléments de la philosophy de Newton, contributed to the popularization of science and Newton's views.
	In 1742, Jean Le Rond D'Alembert introduced the principle which permitted the reduction of a problem in dynamics to one in statics: Kinetic equilibrium is obtained by inventing a fictional force equal in magnitude to the body in question and opposite in acceleration.  This showed that Newton's Third law of motion applies also to bodies free to move.
	In 1742, Pierre Louis Moreau de Maupertius, in Discours sur la Figure des Astres, observed that the nebulous stars, or 'nebulae,' "present the figure of ellipses more or less open" (Maupertius, quoted in Kant 1755:50).
	In 1742, Jean Bernoulli, in Opera omnia, proved that the orbits of objects bound by the inverse square force are conic sections.
	In 1742, Celcius developed the centigrade temperature scale which carries his name.

	In 1744, Guillaume François Rouelle described his neutral saline theory, namely, that salt consisted of a generic component, a chrystalline acid, and a specific component, or whatever substance served to coagulate the acid into a solid.
	In 1744, Georges Louis Leclerc de Buffon announced that the earth had developed for at least 75,000 years.
	In 1744, a 1679 letter from Newton to Boyle was published which described aether in terms of the resistence of the air pushed aside when two glass panes were pushed together and which once together were held thus by the surrounding aether.  British electricians took this to be the latest word on electrical attraction and repulsion (Heilbron 1979:69).
	In 1745, Maupertius, in Venus Physique, proposed the notion of descent from a common ancestor. He also proposed that particles from all parts of the body were gathered in the gonads.
	In 1745, Charles Bonnet demonstrated the regenerative ability of annelid worms.
	In 1746, Bonnet discovered that aphids are parthenogenic.
	In 1746, Étienne Bonnet de Condillac, in Essai sur l'origine des connaissances humaines, developed the theory that all knowledge comes from the senses and there are no innate ideas.
	In 1746, Andreas Cunaeus invented the 'Leyden jar,' a form of capacitor.  It consists of "a glass jar with a layer of metal foil on the outside and a similar layer on the inside.  Contact to the inner foil is by means of a loose chain hanging inside the jar" (Dictionary of Physics 2000:264).  This contraption created a small current which shocked experimenters who quickly demonstrated that a circuit could be extended to hundreds of people (Heilbron 1979:312-318).
	In 1747, Julien de la Mettrie argued, in L'Homme Machine, that thought was a property of organized matter.
	In 1747, Bernard Siegfried Albinus, with the engraver Jan Wandelaar, published Tabulae Sceleti et Musculorum Corporis Humani, a series of illustrations of the human skeleton and successive muscle layers.
	In 1747, Maupertius showed that the impact of a collision between two objects can be analyzed by the 'principle of least action,' in which the path of the motion will follow that which minimizes the action.
	In 1748, Bradley announced that there were tiny deviations in the Earth's axis caused by the pull of the Moon.
	In 1749, Buffon began the publication of the 44 volumes of Histoire Naturelle, in which he drew attention to vestigial organs and asserted that species are mutable.
	In 1750, Thomas Wright, in An Original Theory or New Hypothesis of the Universe, described the Via Lactea, or Milky Way, as a disc, saying we must imagine the stars "all moving the same Way, and not much deviating from the same Plane, as the Planets in their heliocentric Motion do around the solar body" (Wright 1750:137).  Saying that "we have no reason to suppose that the nature of our Sun is different from the rest of the Stars," he took it that there was a great "Multiplicity of Worlds" (ibid.:131).  He also took the 'cloudy stars' to be 'nebulae,' or "an infinite Number of small Stars" (ibid.:101) and speculated that some of these 'spherical' galaxies "may be external Creation," that is, outside the Milky Way, which was at that time considered to be coextensive with the Universe (ibid.:177-178).
	In 1750, Euler, in "Découverte d'un nouveau principe de mécanique," introduced a notation which gives a name and address to every possible point: "Pour trouver le vrai lieu du corps par rapport à chaque instant, on n'aura qu'à le rapporter en même tems à trois plans fixes, qui soient perpendiculaires entr'eux" (Euler 1750:89) (To find the true place of the body at each instant, one only needs to locate it at the same time in respect to the three fixed planes, each perpendicular to the others).
	In 1751, Maupertius, in Système de la Nature, put forward a theory of pangenesis, in which an embryo contained particles derived from all parts of the parent, and heritable novelties arose from changes in fluids or were induced by the environment.
	In 1751, Axel Fredric Cronstedt discovered nickel.
	In 1751, Benjamin Franklin published Experiments and Observations on Electricity after several years of experiments done with several friends.  In this book Franklin suggested an experiment to prove that lightning is a large-scale electrical discharge, a task which later he took upon himself, using a kite.  This led to the invention of the lightning rod.  In Franklin's theory of electricity, "positively electrified bodies repel one another via short-range forces between the particles of their respective atmospheres."  Such an 'atmosphere,' or "aura of electrical matter" is a once the 'charge,' an aether, and the source of the 'electric field' (Heilbron 1981:190), and flowed from the more highly charged body to the less highly charged, on analogy to hydrodynamical principles (Cantor and Hodge 1981:30).  He invented many the terms which are still used: positive, negative, conductor, battery, etc.
	In 1752, René Antoine Ferchault de Réaumur showed by experiment that gastric juice liquifies meat.
	In 1752, James Lind called attention to the value of fresh fruit in the prevention of scurvy.
	In 1752, Thomas Melvill noticed that "the spectra of flames into which metals or salts have been introduced show bright lines characteristic of what has been introduced" (History of Optics 2001:3).
	In 1752, Euler published the proof of the equation relating the number of faces, edges, and vertices of a polyhedron, f+v=e+2.
	In 1753, Carl Linné, better known as Carolus Linneas, published Species plantarum, in which he distinguished plants in terms of genera and species.
	In 1753, Albinus and Wandelaar published Tabulae Ossium Humanorum, an anatomical study of bones.
	In 1753, Euler, in Theoria motus lunae, attempted to solve by analytic function the motions of three interacting bodies, and, though that is not possible by those means, he succeeded in reducing "the relative movements of the Sun, the Earth, and the Moon to a series of elegant equations" (Sobel 1995:970).
	In 1754, Joseph Black heated calcium carbonate which separated into calcium oxide and carbon dioide and then recombined back into calcium carbonate.  He called carbon dioxide 'fixed air' because it could be fixed into solid matter.
	In 1754, Nicolas Louis de Lacaille returned from the Cape of Good Hope where in a four year period he made nearly two thousand additions to the star catalogue.