Misplaced Pages

Astrarium

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.

An astrarium , also called a planetarium , is a medieval astronomical clock made in the 14th century by Italian engineer and astronomer Giovanni Dondi dell'Orologio . The Astrarium was modeled after the solar system and, in addition to counting time and representing calendar dates and holidays, showed how the planets moved around the celestial sphere in one timepiece. This was its main task, in comparison with the astronomical clock, the main task of which is the actual reading of time. A complex mechanism, it combined the functions of a modern planetarium, clock, and calendar into a singular constructive device. Devices that perform this function were known to have been created prior to the design of Dondi, though relatively little is known about them. It is occasionally erroneously claimed by the details of some sources that the Astrarium was the first mechanical device showing the movements of the planets.

#581418

91-568: The first astraria were mechanical devices. Archimedes is said to have used a primitive version that could predict the positions of the Sun , the Moon , and the planets . On May 17, 1902, an archaeologist named Valerios Stais discovered that a lump of oxidated material, which had been recovered from a shipwreck near the Greek island of Antikythera , held within it a mechanism with cogwheels . This mechanism, known as

182-427: A region D in three-dimensional space is given by the triple or volume integral of the constant function f ( x , y , z ) = 1 {\displaystyle f(x,y,z)=1} over the region. It is usually written as: ∭ D 1 d x d y d z . {\displaystyle \iiint _{D}1\,dx\,dy\,dz.} In cylindrical coordinates ,

273-437: A reservoir , the container's volume is modeled by shapes and calculated using mathematics. To ease calculations, a unit of volume is equal to the volume occupied by a unit cube (with a side length of one). Because the volume occupies three dimensions, if the metre (m) is chosen as a unit of length, the corresponding unit of volume is the cubic metre (m ). The cubic metre is also a SI derived unit . Therefore, volume has

364-457: A unit dimension of L . The metric units of volume uses metric prefixes , strictly in powers of ten . When applying prefixes to units of volume, which are expressed in units of length cubed, the cube operators are applied to the unit of length including the prefix. An example of converting cubic centimetre to cubic metre is: 2.3 cm = 2.3 (cm) = 2.3 (0.01 m) = 0.0000023 m (five zeros). Commonly used prefixes for cubed length units are

455-470: A Circle . The actual value is approximately 1.7320508, making this a very accurate estimate. He introduced this result without offering any explanation of how he had obtained it. This aspect of the work of Archimedes caused John Wallis to remark that he was: "as it were of set purpose to have covered up the traces of his investigation as if he had grudged posterity the secret of his method of inquiry while he wished to extort from them assent to his results." It

546-441: A ball into a container after each mile traveled. As legend has it, Archimedes arranged mirrors as a parabolic reflector to burn ships attacking Syracuse using focused sunlight. While there is no extant contemporary evidence of this feat and modern scholars believe it did not happen, Archimedes may have written a work on mirrors entitled Catoptrica , and Lucian and Galen , writing in the second century AD, mentioned that during

637-497: A circle. After four such steps, when the polygons had 96 sides each, he was able to determine that the value of π lay between 3 ⁠ 1 / 7 ⁠ (approx. 3.1429) and 3 ⁠ 10 / 71 ⁠ (approx. 3.1408), consistent with its actual value of approximately 3.1416. He also proved that the area of a circle was equal to π multiplied by the square of the radius of the circle ( π r 2 {\displaystyle \pi r^{2}} ). In On

728-408: A line which rotates with constant angular velocity . Equivalently, in modern polar coordinates ( r , θ ), it can be described by the equation r = a + b θ {\displaystyle \,r=a+b\theta } with real numbers a and b . This is an early example of a mechanical curve (a curve traced by a moving point ) considered by a Greek mathematician. This

819-435: A mischaracterization. Archimedes was able to use indivisibles (a precursor to infinitesimals ) in a way that is similar to modern integral calculus . Through proof by contradiction ( reductio ad absurdum ), he could give answers to problems to an arbitrary degree of accuracy, while specifying the limits within which the answer lay. This technique is known as the method of exhaustion , and he employed it to approximate

910-441: A negative value, similar to length and area . Like all continuous monotonic (order-preserving) measures, volumes of bodies can be compared against each other and thus can be ordered. Volume can also be added together and be decomposed indefinitely; the latter property is integral to Cavalieri's principle and to the infinitesimal calculus of three-dimensional bodies. A 'unit' of infinitesimally small volume in integral calculus

1001-460: A number that was greater than the grains of sand needed to fill the universe. In doing so, he challenged the notion that the number of grains of sand was too large to be counted. He wrote: There are some, King Gelo , who think that the number of the sand is infinite in multitude; and I mean by the sand not only that which exists about Syracuse and the rest of Sicily but also that which is found in every region whether inhabited or uninhabited. To solve

SECTION 10

#1732858932582

1092-728: A person, and focuses on the war machines that he is said to have built in order to defend the city from the Romans. Polybius remarks how, during the Second Punic War , Syracuse switched allegiances from Rome to Carthage , resulting in a military campaign under the command of Marcus Claudius Marcellus and Appius Claudius Pulcher , who besieged the city from 213 to 212 BC. He notes that the Romans underestimated Syracuse's defenses, and mentions several machines Archimedes designed, including improved catapults , crane-like machines that could be swung around in an arc, and other stone-throwers . Although

1183-446: A range of geometrical theorems . These include the area of a circle , the surface area and volume of a sphere , the area of an ellipse , the area under a parabola , the volume of a segment of a paraboloid of revolution , the volume of a segment of a hyperboloid of revolution , and the area of a spiral . Archimedes' other mathematical achievements include deriving an approximation of pi ( π ) , defining and investigating

1274-603: A reference to the mathematical drawing that he was supposedly studying when disturbed by the Roman soldier. There is no reliable evidence that Archimedes uttered these words and they do not appear in Plutarch's account. A similar quotation is found in the work of Valerius Maximus (fl. 30 AD), who wrote in Memorable Doings and Sayings , " ... sed protecto manibus puluere 'noli' inquit, 'obsecro, istum disturbare' " ("... but protecting

1365-408: A solution that applied the hydrostatics principle known as Archimedes' principle , found in his treatise On Floating Bodies : a body immersed in a fluid experiences a buoyant force equal to the weight of the fluid it displaces. Using this principle, it would have been possible to compare the density of the crown to that of pure gold by balancing it on a scale with a pure gold reference sample of

1456-404: A temple dedicated to the goddess Aphrodite among its facilities. The account also mentions that, in order to remove any potential water leaking through the hull, a device with a revolving screw-shaped blade inside a cylinder was designed by Archimedes. Archimedes' screw was turned by hand, and could also be used to transfer water from a low-lying body of water into irrigation canals. The screw

1547-463: Is 4 π r for the sphere, and 6 π r for the cylinder (including its two bases), where r is the radius of the sphere and cylinder. This work of 28 propositions is also addressed to Dositheus. The treatise defines what is now called the Archimedean spiral . It is the locus of points corresponding to the locations over time of a point moving away from a fixed point with a constant speed along

1638-412: Is a work in 32 propositions addressed to Dositheus. In this treatise Archimedes calculates the areas and volumes of sections of cones , spheres, and paraboloids. Volume Volume is a measure of regions in three-dimensional space . It is often quantified numerically using SI derived units (such as the cubic metre and litre ) or by various imperial or US customary units (such as

1729-646: Is also credited with designing innovative machines , such as his screw pump , compound pulleys , and defensive war machines to protect his native Syracuse from invasion. Archimedes died during the siege of Syracuse , when he was killed by a Roman soldier despite orders that he should not be harmed. Cicero describes visiting Archimedes' tomb, which was surmounted by a sphere and a cylinder that Archimedes requested be placed there to represent his most valued mathematical discovery. Unlike his inventions, Archimedes' mathematical writings were little known in antiquity. Alexandrian mathematicians read and quoted him, but

1820-431: Is common for measuring small volume of fluids or granular materials , by using a multiple or fraction of the container. For granular materials, the container is shaken or leveled off to form a roughly flat surface. This method is not the most accurate way to measure volume but is often used to measure cooking ingredients . Air displacement pipette is used in biology and biochemistry to measure volume of fluids at

1911-499: Is possible that he used an iterative procedure to calculate these values. In Quadrature of the Parabola , Archimedes proved that the area enclosed by a parabola and a straight line is ⁠ 4 / 3 ⁠ times the area of a corresponding inscribed triangle as shown in the figure at right. He expressed the solution to the problem as an infinite geometric series with the common ratio ⁠ 1 / 4 ⁠ : If

SECTION 20

#1732858932582

2002-518: Is still in use today for pumping liquids and granulated solids such as coal and grain. Described by Vitruvius , Archimedes' device may have been an improvement on a screw pump that was used to irrigate the Hanging Gardens of Babylon . The world's first seagoing steamship with a screw propeller was the SS Archimedes , which was launched in 1839 and named in honor of Archimedes and his work on

2093-634: Is the volume element ; this formulation is useful when working with different coordinate systems , spaces and manifolds . The oldest way to roughly measure a volume of an object is using the human body, such as using hand size and pinches . However, the human body's variations make it extremely unreliable. A better way to measure volume is to use roughly consistent and durable containers found in nature, such as gourds , sheep or pig stomachs , and bladders . Later on, as metallurgy and glass production improved, small volumes nowadays are usually measured using standardized human-made containers. This method

2184-503: Is used when integrating by an axis parallel to the axis of rotation. The general equation can be written as: V = π ∫ a b | f ( x ) 2 − g ( x ) 2 | d x {\displaystyle V=\pi \int _{a}^{b}\left|f(x)^{2}-g(x)^{2}\right|\,dx} where f ( x ) {\textstyle f(x)} and g ( x ) {\textstyle g(x)} are

2275-525: The Antikythera mechanism , was recently redated to end of the 2nd century BCE. Extensive study of the fragments, using X-rays, has revealed enough details (gears, pinions, crank) to enable researchers to build partial replicas of the original device. Engraved on the major gears are the names of the planets, which leaves little doubt as to the intended use of the mechanism. By the collapse of the Roman Empire ,

2366-449: The Archimedean spiral , and devising a system using exponentiation for expressing very large numbers . He was also one of the first to apply mathematics to physical phenomena , working on statics and hydrostatics . Archimedes' achievements in this area include a proof of the law of the lever , the widespread use of the concept of center of gravity , and the enunciation of the law of buoyancy known as Archimedes' principle . He

2457-559: The Byzantine Greek architect Isidore of Miletus ( c.  530 AD ), while commentaries on the works of Archimedes written by Eutocius in the same century helped bring his work to a wider audience. Archimedes' work was translated into Arabic by Thābit ibn Qurra (836–901 AD), and into Latin via Arabic by Gerard of Cremona (c. 1114–1187). Direct Greek to Latin translations were later done by William of Moerbeke (c. 1215–1286) and Iacobus Cremonensis (c. 1400–1453). During

2548-711: The Moscow Mathematical Papyrus (c. 1820 BCE). In the Reisner Papyrus , ancient Egyptians have written concrete units of volume for grain and liquids, as well as a table of length, width, depth, and volume for blocks of material. The Egyptians use their units of length (the cubit , palm , digit ) to devise their units of volume, such as the volume cubit or deny (1 cubit × 1 cubit × 1 cubit), volume palm (1 cubit × 1 cubit × 1 palm), and volume digit (1 cubit × 1 cubit × 1 digit). The last three books of Euclid's Elements , written in around 300 BCE, detailed

2639-573: The Renaissance and again in the 17th century , while the discovery in 1906 of previously lost works by Archimedes in the Archimedes Palimpsest has provided new insights into how he obtained mathematical results. Archimedes was born c. 287 BC in the seaport city of Syracuse , Sicily , at that time a self-governing colony in Magna Graecia . The date of birth is based on a statement by

2730-526: The Renaissance , the Editio princeps (First Edition) was published in Basel in 1544 by Johann Herwagen with the works of Archimedes in Greek and Latin. The following are ordered chronologically based on new terminological and historical criteria set by Knorr (1978) and Sato (1986). This is a short work consisting of three propositions. It is written in the form of a correspondence with Dositheus of Pelusium, who

2821-623: The astronomical clock in the Piazzi dei Signori, Padua , in 1344 – one of the first of its type. In later ages, more astraria were built. A famous example is the Eise Eisinga Planetarium , built in 1774 by Eise Eisinga from Dronrijp, Friesland, the Netherlands. It displayed all the planets and was fixed to the ceiling in a house in Franeker , where it can still be visited. In modern times,

Astrarium - Misplaced Pages Continue

2912-410: The cube , cuboid and cylinder , they have an essentially the same volume calculation formula as one for the prism : the base of the shape multiplied by its height . The calculation of volume is a vital part of integral calculus. One of which is calculating the volume of solids of revolution , by rotating a plane curve around a line on the same plane. The washer or disc integration method

3003-402: The gallon , quart , cubic inch ). The definition of length and height (cubed) is interrelated with volume. The volume of a container is generally understood to be the capacity of the container; i.e., the amount of fluid (gas or liquid) that the container could hold, rather than the amount of space the container itself displaces. By metonymy , the term "volume" sometimes is used to refer to

3094-475: The heliocentric theory of the solar system proposed by Aristarchus of Samos , as well as contemporary ideas about the size of the Earth and the distance between various celestial bodies . By using a system of numbers based on powers of the myriad , Archimedes concludes that the number of grains of sand required to fill the universe is 8 × 10 in modern notation. The introductory letter states that Archimedes' father

3185-574: The imperial gallon was defined to be the volume occupied by ten pounds of water at 17 °C (62 °F). This definition was further refined until the United Kingdom's Weights and Measures Act 1985 , which makes 1 imperial gallon precisely equal to 4.54609 litres with no use of water. The 1960 redefinition of the metre from the International Prototype Metre to the orange-red emission line of krypton-86 atoms unbounded

3276-622: The lever , he gave a mathematical proof of the principle involved in his work On the Equilibrium of Planes . Earlier descriptions of the principle of the lever are found in a work by Euclid and in the Mechanical Problems , belonging to the Peripatetic school of the followers of Aristotle , the authorship of which has been attributed by some to Archytas . There are several, often conflicting, reports regarding Archimedes' feats using

3367-509: The sester , amber , coomb , and seam . The sheer quantity of such units motivated British kings to standardize them, culminated in the Assize of Bread and Ale statute in 1258 by Henry III of England . The statute standardized weight, length and volume as well as introduced the peny, ounce, pound, gallon and bushel. In 1618, the London Pharmacopoeia (medicine compound catalog) adopted

3458-439: The siege of Syracuse Archimedes had burned enemy ships. Nearly four hundred years later, Anthemius , despite skepticism, tried to reconstruct Archimedes' hypothetical reflector geometry. The purported device, sometimes called " Archimedes' heat ray ", has been the subject of an ongoing debate about its credibility since the Renaissance . René Descartes rejected it as false, while modern researchers have attempted to recreate

3549-439: The volume integral is ∭ D r d r d θ d z , {\displaystyle \iiint _{D}r\,dr\,d\theta \,dz,} In spherical coordinates (using the convention for angles with θ {\displaystyle \theta } as the azimuth and φ {\displaystyle \varphi } measured from the polar axis; see more on conventions ),

3640-535: The Byzantine Greek scholar John Tzetzes that Archimedes lived for 75 years before his death in 212 BC. Plutarch wrote in his Parallel Lives that Archimedes was related to King Hiero II , the ruler of Syracuse, although Cicero suggests he was of humble origin. In the Sand-Reckoner , Archimedes gives his father's name as Phidias, an astronomer about whom nothing else is known. A biography of Archimedes

3731-473: The Earth" ( Greek : δῶς μοι πᾶ στῶ καὶ τὰν γᾶν κινάσω ). Olympiodorus later attributed the same boast to Archimedes' invention of the baroulkos , a kind of windlass , rather than the lever. A large part of Archimedes' work in engineering probably arose from fulfilling the needs of his home city of Syracuse . Athenaeus of Naucratis quotes a certain Moschion in a description on how King Hiero II commissioned

Astrarium - Misplaced Pages Continue

3822-509: The Earth, Sun, and Moon, as well as Aristarchus ' heliocentric model of the universe, in the Sand-Reckoner . Without the use of either trigonometry or a table of chords, Archimedes determines the Sun's apparent diameter by first describing the procedure and instrument used to make observations (a straight rod with pegs or grooves), applying correction factors to these measurements, and finally giving

3913-439: The Roman gallon or congius as a basic unit of volume and gave a conversion table to the apothecaries' units of weight. Around this time, volume measurements are becoming more precise and the uncertainty is narrowed to between 1–5 mL (0.03–0.2 US fl oz; 0.04–0.2 imp fl oz). Around the early 17th century, Bonaventura Cavalieri applied the philosophy of modern integral calculus to calculate

4004-566: The Romans ultimately captured the city, they suffered considerable losses due to Archimedes' inventiveness. Cicero (106–43 BC) mentions Archimedes in some of his works. While serving as a quaestor in Sicily, Cicero found what was presumed to be Archimedes' tomb near the Agrigentine gate in Syracuse, in a neglected condition and overgrown with bushes. Cicero had the tomb cleaned up and was able to see

4095-518: The Sphere and Cylinder , Archimedes postulates that any magnitude when added to itself enough times will exceed any given magnitude. Today this is known as the Archimedean property of real numbers. Archimedes gives the value of the square root of 3 as lying between ⁠ 265 / 153 ⁠ (approximately 1.7320261) and ⁠ 1351 / 780 ⁠ (approximately 1.7320512) in Measurement of

4186-477: The ancient city of Syracuse in Sicily . Although few details of his life are known, he is regarded as one of the leading scientists in classical antiquity . Regarded as the greatest mathematician of ancient history , and one of the greatest of all time, Archimedes anticipated modern calculus and analysis by applying the concept of the infinitely small and the method of exhaustion to derive and rigorously prove

4277-412: The areas of figures and the value of π . In Measurement of a Circle , he did this by drawing a larger regular hexagon outside a circle then a smaller regular hexagon inside the circle, and progressively doubling the number of sides of each regular polygon , calculating the length of a side of each polygon at each step. As the number of sides increases, it becomes a more accurate approximation of

4368-588: The astrarium has grown into a tourist attraction as a commercially exploited planetarium -showing in IMAX theaters, with such presentations as The History of the Universe , as well as other astronomical phenomena. Archimedes Archimedes of Syracuse ( / ˌ ɑːr k ɪ ˈ m iː d iː z / AR -kim- EE -deez ; c.  287  – c.  212   BC ) was an Ancient Greek mathematician , physicist , engineer , astronomer , and inventor from

4459-416: The capture of Syracuse and Archimedes' role in it. Plutarch (45–119 AD) provides at least two accounts on how Archimedes died after Syracuse was taken. According to the most popular account, Archimedes was contemplating a mathematical diagram when the city was captured. A Roman soldier commanded him to come and meet Marcellus, but he declined, saying that he had to finish working on the problem. This enraged

4550-419: The capture of Syracuse in the Second Punic War , Marcellus is said to have taken back to Rome two mechanisms which were constructed by Archimedes and which showed the motion of the Sun, Moon and five planets. Cicero also mentions similar mechanisms designed by Thales of Miletus and Eudoxus of Cnidus . The dialogue says that Marcellus kept one of the devices as his only personal loot from Syracuse, and donated

4641-431: The carving and read some of the verses that had been added as an inscription. The tomb carried a sculpture illustrating Archimedes' favorite mathematical proof , that the volume and surface area of the sphere are two-thirds that of an enclosing cylinder including its bases. He also mentions that Marcellus brought to Rome two planetariums Archimedes built. The Roman historian Livy (59 BC–17 AD) retells Polybius's story of

SECTION 50

#1732858932582

4732-444: The construction of these mechanisms entitled On Sphere-Making . Modern research in this area has been focused on the Antikythera mechanism , another device built c.  100 BC probably designed with a similar purpose. Constructing mechanisms of this kind would have required a sophisticated knowledge of differential gearing . This was once thought to have been beyond the range of the technology available in ancient times, but

4823-487: The contained volume does not need to fill towards the container's capacity, or vice versa. Containers can only hold a specific amount of physical volume, not weight (excluding practical concerns). For example, a 50,000 bbl (7,900,000 L) tank that can just hold 7,200 t (15,900,000 lb) of fuel oil will not be able to contain the same 7,200 t (15,900,000 lb) of naphtha , due to naphtha's lower density and thus larger volume. For many shapes such as

4914-532: The corresponding region (e.g., bounding volume ). In ancient times, volume was measured using similar-shaped natural containers. Later on, standardized containers were used. Some simple three-dimensional shapes can have their volume easily calculated using arithmetic formulas . Volumes of more complicated shapes can be calculated with integral calculus if a formula exists for the shape's boundary. Zero- , one- and two-dimensional objects have no volume; in four and higher dimensions, an analogous concept to

5005-399: The cubic millimetre (mm ), cubic centimetre (cm ), cubic decimetre (dm ), cubic metre (m ) and the cubic kilometre (km ). The conversion between the prefix units are as follows: 1000 mm = 1 cm , 1000 cm = 1 dm , and 1000 dm = 1 m . The metric system also includes the litre (L) as a unit of volume, where 1 L = 1 dm = 1000 cm = 0.001 m . For

5096-464: The density would be lower than that of gold. Archimedes found that this is what had happened, proving that silver had been mixed in. The story of the golden crown does not appear anywhere in Archimedes' known works. The practicality of the method described has been called into question due to the extreme accuracy that would be required to measure water displacement . Archimedes may have instead sought

5187-451: The design of a huge ship, the Syracusia , which could be used for luxury travel, carrying supplies, and as a display of naval power . The Syracusia is said to have been the largest ship built in classical antiquity and, according to Moschion's account, it was launched by Archimedes. The ship presumably was capable of carrying 600 people and included garden decorations, a gymnasium , and

5278-610: The dialect of ancient Syracuse. Many written works by Archimedes have not survived or are only extant in heavily edited fragments; at least seven of his treatises are known to have existed due to references made by other authors. Pappus of Alexandria mentions On Sphere-Making and another work on polyhedra , while Theon of Alexandria quotes a remark about refraction from the now-lost Catoptrica . Archimedes made his work known through correspondence with mathematicians in Alexandria . The writings of Archimedes were first collected by

5369-518: The discovery of the Antikythera mechanism in 1902 has confirmed that devices of this kind were known to the ancient Greeks. While he is often regarded as a designer of mechanical devices, Archimedes also made contributions to the field of mathematics . Plutarch wrote that Archimedes "placed his whole affection and ambition in those purer speculations where there can be no reference to the vulgar needs of life", though some scholars believe this may be

5460-426: The dust with his hands, said 'I beg of you, do not disturb this ' "). The most widely known anecdote about Archimedes tells of how he invented a method for determining the volume of an object with an irregular shape. According to Vitruvius , a crown for a temple had been made for King Hiero II of Syracuse , who supplied the pure gold to be used. The crown was likely made in the shape of a votive wreath . Archimedes

5551-609: The effect using only the means that would have been available to Archimedes, mostly with negative results. It has been suggested that a large array of highly polished bronze or copper shields acting as mirrors could have been employed to focus sunlight onto a ship, but the overall effect would have been blinding, dazzling , or distracting the crew of the ship rather than fire. Using modern materials and larger scale, sunlight-concentrating solar furnaces can reach very high temperatures, and are sometimes used for generating electricity . Archimedes discusses astronomical measurements of

SECTION 60

#1732858932582

5642-533: The exact formulas for calculating the volume of parallelepipeds , cones, pyramids , cylinders, and spheres . The formula were determined by prior mathematicians by using a primitive form of integration , by breaking the shapes into smaller and simpler pieces. A century later, Archimedes ( c.  287 – 212 BCE ) devised approximate volume formula of several shapes using the method of exhaustion approach, meaning to derive solutions from previous known formulas from similar shapes. Primitive integration of shapes

5733-527: The feasibility of the claw, and in 2005 a television documentary entitled Superweapons of the Ancient World built a version of the claw and concluded that it was a workable device. Archimedes has also been credited with improving the power and accuracy of the catapult , and with inventing the odometer during the First Punic War . The odometer was described as a cart with a gear mechanism that dropped

5824-535: The first comprehensive compilation was not made until c.  530   AD by Isidore of Miletus in Byzantine Constantinople , while Eutocius ' commentaries on Archimedes' works in the same century opened them to wider readership for the first time. The relatively few copies of Archimedes' written work that survived through the Middle Ages were an influential source of ideas for scientists during

5915-519: The first term in this series is the area of the triangle, then the second is the sum of the areas of two triangles whose bases are the two smaller secant lines , and whose third vertex is where the line that is parallel to the parabola's axis and that passes through the midpoint of the base intersects the parabola, and so on. This proof uses a variation of the series 1/4 + 1/16 + 1/64 + 1/256 + · · · which sums to  ⁠ 1 / 3 ⁠ . In The Sand Reckoner , Archimedes set out to calculate

6006-473: The globe, it happened that the Moon followed the Sun by as many turns on that bronze contrivance as in the sky itself, from which also in the sky the Sun's globe became to have that same eclipse, and the Moon came then to that position which was its shadow on the Earth when the Sun was in line. This is a description of a small planetarium . Pappus of Alexandria reports on a now lost treatise by Archimedes dealing with

6097-505: The golden crown to find its volume, and thus its density and purity, due to the extreme precision involved. Instead, he likely have devised a primitive form of a hydrostatic balance . Here, the crown and a chunk of pure gold with a similar weight are put on both ends of a weighing scale submerged underwater, which will tip accordingly due to the Archimedes' principle . In the Middle Ages , many units for measuring volume were made, such as

6188-442: The know-how and science behind this piece of clockwork was lost. According to historians Bedini and Maddison , the earliest astrarium clock with an "almost complete description and incontestable documentation" to have survived is the astrarium completed in 1364 by Giovanni de' Dondi (1318–1388), a scholar and physician of the Middle Ages . The original clock, consisting of 107 wheels and pinions , has been lost, perhaps during

6279-416: The lever to lift very heavy objects. Plutarch describes how Archimedes designed block-and-tackle pulley systems, allowing sailors to use the principle of leverage to lift objects that would otherwise have been too heavy to move. According to Pappus of Alexandria , Archimedes' work on levers and his understanding of mechanical advantage caused him to remark: "Give me a place to stand on, and I will move

6370-415: The litre unit, the commonly used prefixes are the millilitre (mL), centilitre (cL), and the litre (L), with 1000 mL = 1 L, 10 mL = 1 cL, 10 cL = 1 dL, and 10 dL = 1 L. Various other imperial or U.S. customary units of volume are also in use, including: Capacity is the maximum amount of material that a container can hold, measured in volume or weight . However,

6461-580: The metre, cubic metre, and litre from physical objects. This also make the metre and metre-derived units of volume resilient to changes to the International Prototype Metre. The definition of the metre was redefined again in 1983 to use the speed of light and second (which is derived from the caesium standard ) and reworded for clarity in 2019 . As a measure of the Euclidean three-dimensional space , volume cannot be physically measured as

6552-598: The microscopic scale. Calibrated measuring cups and spoons are adequate for cooking and daily life applications, however, they are not precise enough for laboratories . There, volume of liquids is measured using graduated cylinders , pipettes and volumetric flasks . The largest of such calibrated containers are petroleum storage tanks , some can hold up to 1,000,000  bbl (160,000,000 L) of fluids. Even at this scale, by knowing petroleum's density and temperature, very precise volume measurement in these tanks can still be made. For even larger volumes such as in

6643-505: The modern integral calculus, which remains in use in the 21st century. On 7 April 1795, the metric system was formally defined in French law using six units. Three of these are related to volume: the stère  (1 m ) for volume of firewood; the litre  (1 dm ) for volumes of liquid; and the gramme , for mass—defined as the mass of one cubic centimetre of water at the temperature of melting ice. Thirty years later in 1824,

6734-450: The normal volume is the hypervolume. The precision of volume measurements in the ancient period usually ranges between 10–50 mL (0.3–2 US fl oz; 0.4–2 imp fl oz). The earliest evidence of volume calculation came from ancient Egypt and Mesopotamia as mathematical problems, approximating volume of simple shapes such as cuboids , cylinders , frustum and cones . These math problems have been written in

6825-576: The other to the Temple of Virtue in Rome. Marcellus's mechanism was demonstrated, according to Cicero, by Gaius Sulpicius Gallus to Lucius Furius Philus , who described it thus: Hanc sphaeram Gallus cum moveret, fiebat ut soli luna totidem conversionibus in aere illo quot diebus in ipso caelo succederet, ex quo et in caelo sphaera solis fieret eadem illa defectio, et incideret luna tum in eam metam quae esset umbra terrae, cum sol e regione. When Gallus moved

6916-409: The plane curve boundaries. The shell integration method is used when integrating by an axis perpendicular to the axis of rotation. The equation can be written as: V = 2 π ∫ a b x | f ( x ) − g ( x ) | d x {\displaystyle V=2\pi \int _{a}^{b}x|f(x)-g(x)|\,dx} The volume of

7007-420: The principles derived to calculate the areas and centers of gravity of various geometric figures including triangles , parallelograms and parabolas . In this work of 24 propositions addressed to Dositheus, Archimedes proves by two methods that the area enclosed by a parabola and a straight line is 4/3 the area of a triangle with equal base and height. He achieves this in one of his proofs by calculating

7098-490: The problem, Archimedes devised a system of counting based on the myriad . The word itself derives from the Greek μυριάς , murias , for the number 10,000. He proposed a number system using powers of a myriad of myriads (100 million, i.e., 10,000 x 10,000) and concluded that the number of grains of sand required to fill the universe would be 8 vigintillion , or 8 × 10 . The works of Archimedes were written in Doric Greek ,

7189-452: The result in the form of upper and lower bounds to account for observational error. Ptolemy , quoting Hipparchus, also references Archimedes' solstice observations in the Almagest . This would make Archimedes the first known Greek to have recorded multiple solstice dates and times in successive years. Cicero's De re publica portrays a fictional conversation taking place in 129 BC. After

7280-492: The sacking of Mantua in 1630, but de' Dondi left detailed descriptions, which have survived, enabling a reconstruction of the clock. It displays the mean time, sidereal (or star) time and the motions of the Sun, Moon and the five then-known planets Venus , Mars , Saturn , Mercury , and Jupiter . It was conceived according to a Ptolemaic conception of the Solar System. De' Dondi was inspired by his father Jacopo who designed

7371-453: The same weight, then immersing the apparatus in water. The difference in density between the two samples would cause the scale to tip accordingly. Galileo Galilei , who invented a hydrostatic balance in 1586 inspired by Archimedes' work, considered it "probable that this method is the same that Archimedes followed, since, besides being very accurate, it is based on demonstrations found by Archimedes himself." While Archimedes did not invent

7462-416: The screw. Archimedes is said to have designed a claw as a weapon to defend the city of Syracuse. Also known as " the ship shaker ", the claw consisted of a crane-like arm from which a large metal grappling hook was suspended. When the claw was dropped onto an attacking ship the arm would swing upwards, lifting the ship out of the water and possibly sinking it. There have been modern experiments to test

7553-559: The soldier, who killed Archimedes with his sword. Another story has Archimedes carrying mathematical instruments before being killed because a soldier thought they were valuable items. Marcellus was reportedly angered by Archimedes' death, as he considered him a valuable scientific asset (he called Archimedes "a geometrical Briareus ") and had ordered that he should not be harmed. The last words attributed to Archimedes are " Do not disturb my circles " ( Latin , " Noli turbare circulos meos "; Katharevousa Greek , "μὴ μου τοὺς κύκλους τάραττε"),

7644-418: The value of a geometric series that sums to infinity with the ratio 1/4. In this two-volume treatise addressed to Dositheus, Archimedes obtains the result of which he was most proud, namely the relationship between a sphere and a circumscribed cylinder of the same height and diameter . The volume is ⁠ 4 / 3 ⁠ π r for the sphere, and 2 π r for the cylinder. The surface area

7735-399: The volume of any object. He devised Cavalieri's principle , which said that using thinner and thinner slices of the shape would make the resulting volume more and more accurate. This idea would then be later expanded by Pierre de Fermat , John Wallis , Isaac Barrow , James Gregory , Isaac Newton , Gottfried Wilhelm Leibniz and Maria Gaetana Agnesi in the 17th and 18th centuries to form

7826-411: Was a student of Conon of Samos . In Proposition II, Archimedes gives an approximation of the value of pi ( π ), showing that it is greater than ⁠ 223 / 71 ⁠ (3.1408...) and less than ⁠ 22 / 7 ⁠ (3.1428...). In this treatise, also known as Psammites , Archimedes finds a number that is greater than the grains of sand needed to fill the universe. This book mentions

7917-495: Was also discovered independently by Liu Hui in the 3rd century CE, Zu Chongzhi in the 5th century CE, the Middle East and India . Archimedes also devised a way to calculate the volume of an irregular object, by submerging it underwater and measure the difference between the initial and final water volume. The water volume difference is the volume of the object. Though highly popularized, Archimedes probably does not submerge

8008-494: Was an astronomer named Phidias. The Sand Reckoner is the only surviving work in which Archimedes discusses his views on astronomy. There are two books to On the Equilibrium of Planes : the first contains seven postulates and fifteen propositions , while the second book contains ten propositions. In the first book, Archimedes proves the law of the lever , which states that: Magnitudes are in equilibrium at distances reciprocally proportional to their weights. Archimedes uses

8099-417: Was asked to determine whether some silver had been substituted by the goldsmith without damaging the crown, so he could not melt it down into a regularly shaped body in order to calculate its density . In this account, Archimedes noticed while taking a bath that the level of the water in the tub rose as he got in, and realized that this effect could be used to determine the golden crown's volume . Archimedes

8190-471: Was so excited by this discovery that he took to the streets naked, having forgotten to dress, crying " Eureka !" ( Greek : "εὕρηκα , heúrēka !, lit.   ' I have found [it]! ' ). For practical purposes water is incompressible, so the submerged crown would displace an amount of water equal to its own volume. By dividing the mass of the crown by the volume of water displaced, its density could be obtained; if cheaper and less dense metals had been added,

8281-783: Was written by his friend Heracleides, but this work has been lost, leaving the details of his life obscure. It is unknown, for instance, whether he ever married or had children, or if he ever visited Alexandria , Egypt, during his youth. From his surviving written works, it is clear that he maintained collegial relations with scholars based there, including his friend Conon of Samos and the head librarian Eratosthenes of Cyrene . The standard versions of Archimedes' life were written long after his death by Greek and Roman historians. The earliest reference to Archimedes occurs in The Histories by Polybius ( c. 200–118 BC), written about 70 years after his death. It sheds little light on Archimedes as

#581418