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2 22 April 1571 – 24 January 1645

3 an Italian Engineer and architect Invented the first modern steam engine, one that turned a turbine and thus could be used to do actual.

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5 Branca designed many different mechanical inventions, a collection of which he dedicated to Cenci, the governor of Loreto, Ancona. The work contains 63 engravings with descriptions in Italian and Latin and was an example of the Theater of machines genre which had appeared in the 16th century, named after Jacques Besson's Theatrum Instrumentorum of 1571. However, where Besson's book had been beautifully illustrated with engravings, Branca's book was a small octavo volume illustrated with relatively poor quality woodcuts.

6 Branca's so-called steam engine appears as the 25th plate in Le Machine. It comprises a wheel with flat vanes like a paddlewheel, shown being rotated by steam produced in a closed vessel and directed at the vanes through a pipe (and hence would be more appropriately called a steam turbine). Branca suggested that it might be used for powering pestles and mortars, grinding machines, raising water, and sawing wood. It bears no relation to any later application of steam power and is not much of an advance over the aeolipile described by Hero of Alexandria in the first century AD.

7 he eventually published in book form in his best known work, written in Italian and Latin, Le Machine (The Machine). Rather than expensive engravings, it is illustrated with 63 economical woodcuts of various ingenious devices, including his steam engine. This was basically a large spheroid shaped boiling vessel which ended in a tapered neck that emitted a powerful jet of steam that was directed towards the blades of a paddle wheel. He explained that with proper gearing, rods and shafts it could be used to power grinders, stamping machines, lumber mills and to pump water, a use which James Watt, who is usually credited with the invention of the steam engine, adapted.

8 Branca himself designed a steam powered stamping mill, the first machine to use an impulse turbine. Sir Isaac Newton used components of Branca’s engine to power a steam wagon, and in 1791 John Barber added a compressor to it, the prototype of the modern gas turbine which powers motor vehicles. Ironically, Italy was one of the last European countries to industrialize, a major reason being the lack of coal and iron which made the widespread use of steam engines practical. Nevertheless, Giovanni Branca deserves a place of honor as one of those who made it all possible.

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10 an English astronomer, mathematician and maker of scientific instruments from Middleton, Leeds who invented the micrometer. He was one of a group of astronomers in the north of England who followed the astronomy of Johannes Kepler which included, Jeremiah Horrocks and William Crabtree.

11 In the late 1630s, Gascoigne, was working on a Keplerian optical arrangement when a thread from a spider’s web happened to become caught at exactly the combined optical focal points of the two lenses. When he looked through the arrangement Gascoigne saw the web bright and sharp within the field of view. He realized that he could more accurately point the telescope using the line as a guide, and went on to invent the telescopic sight by placing crossed wires at the focal point to define the centre of the field of view.[2] He then added this arrangement to a sextant modelled on the instrument used by Tycho Brahe, although Tycho’s sextant was only a naked- eye instrument.

12 Gascoigne's sextant was five feet in radius, and measured the distance between astronomical bodies to an unprecedented degree of accuracy. Gascoigne then realised that by introducing two points, whose separation could be adjusted using a screw, he could measure the size of the image enclosed by them. Using the known pitch of the screw, and knowing the focal length of the lens producing the image, he could work out the size of the object, such as the Moon or the planets, to a hitherto unattainable degree of accuracy.

13 This invention was later taken up and improved by the scientist and astronomer Richard Towneley who was the nephew of Gascoigne's friend Christopher Towneley. Towneley later brought the instrument to the attention of Robert Hooke, who used it to calculate the size of comets and other celestial bodies. The micrometer, as it became known, was to lie at the heart of astronomical measurement down to the twentieth century.

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15 Gascoigne died at the Battle of Marston Moor, Yorkshire, on 2 July 1644 as did Charles Towneley, the father of his friend Richard Towneley.

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17 an Italian physicist and mathematician, best known for his invention of the barometer, but is also known for his advances in optics and work on the method of indivisibles.

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19 Barometer Torricelli's chief invention was the mercury barometer. "This instrument is named from two Greek words, signifying two measures of weight, since by it a column of air is weighed against a column of mercury."[8] The barometer arose from the need to solve a practical problem. Pump makers of the Grand Duke of Tuscany attempted to raise water to a height of 12 meters or more, but found that 10 meters was the limit with a suction pump (as recounted in Galileo's Dialogue). Torricelli employed mercury, thirteen times more dense than water. In 1643 he created a tube approximately one meter long, sealed at the top, filled it with mercury, and set it vertically into a basin of mercury.

20 The column of mercury fell to about 76 cm, leaving a Torricellian vacuum above. As we now know, the column's height fluctuated with changing atmospheric pressure; this was the first barometer. The discovery of the principle of the barometer has perpetuated his fame ("Torricellian tube", "Torricellian vacuum"). The torr, a unit of pressure used in vacuum measurements, is named after him. "12 years before Torricelli's observations, Descartes, the French philosopher, had made the same observation, although he does not appear to have turned it to any account."

21 Torricelli's law Torricelli also discovered Torricelli's Law, regarding the speed of a fluid flowing out of an opening, which was later shown to be a particular case of Bernoulli's principle. "Evangelista Torricelli found that water leaks out a small hole in the bottom of a container at a rate proportional to the square root of the depth of the water. So if the container is an upright cylinder with a small leak at the bottom and y is the depth of the water at time t, then d y d t = − k u ( y ) y {\displaystyle {\frac {dy}{dt}}=- k{\sqrt {u(y)y}}} \frac{dy}{dt} = -k \sqrt{u(y)y} for some constant k > 0."[9]

22 The study of projectiles Torricelli studied projectiles and how they traveled through the air. "Perhaps his most notable achievement in the field of projectiles was to establish for the first time the idea of an envelope: projectiles sent out at [...] the same speed in all directions trace out parabolas which are all tangent to a common paraboloid. This envelope became known as the parabola di sicurezza (safety parabola)."[2]

23 Cause of wind Torricelli gave the first scientific description of the cause of wind:... winds are produced by differences of air temperature, and hence density, between two regions of the earth.

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25 In 1642, inspired by the idea of making his father's job of calculating taxes easier, Blaise Pascal started work on a calculator dubbed the Pascaline. The Pascaline was a numerical wheel calculator with movable dials, each representing a numerical digit. The invention, however, was not without its glitches: There was a discrepancy between the calculator's design and the structure of French currency at the time.

26 Pascal continued to work on improving the device, with 50 prototypes produced by 1652, but the Pascaline was never a big seller. In 1648, Pascal starting writing more of his theorems in The Generation of Conic Sections, but he pushed the work aside until the following decade.

27 At the end of the 1640s, Pascal temporarily focused his experiments on the physical sciences. Following in Evangelista Torricelli’s footsteps, Pascal experimented with how atmospheric pressure could be estimated in terms of weight. In 1648, by having his brother-in-law take readings of the barometric pressure at various altitudes on a mountain (Pascal was too poor of health to make the trek himself), he validated Torricelli's theory concerning the cause of barometrical variations.

28 In the 1650s, Pascal set about trying to create a perpetual motion machine, the purpose of which was to produce more energy than it used. In the process, he stumbled upon an accidental invention and in 1655 Pascal's roulette machine was born. Aptly, he derived its name from the French word for "little wheel."

29 Overlapping his work on the roulette machine was Pascal's correspondence with mathematical theorist Pierre de Fermat, which began in 1654. Through their letters discussing gambling and Pascal's own experiments, he found that there is a fixed likelihood of a particular outcome when it comes to the roll of the dice. This discovery was the basis of the mathematical theory of probability, with Pascal's writings on the subject published posthumously.

30 Although the specific dates are uncertain, Pascal also reportedly invented a primitive form of the wristwatch. It was an informal invention to say the least: The mathematician was known to strap his pocket watch to his wrist with a piece of string, presumably for the sake of convenience while tinkering with other inventions.

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