Happy Pi Day! 3.14(159265359...) I'm sure you've heard it, perhaps even celebrated it! I'm lucky enough to have a sister who bakes, so we celebrated it quite often as a family. So who do we have to thank for yet another day to celebrate? Archimedes of Syracuse!

Archimedes was born 287 BC in Syracuse, Sicily, Italy. He is arguably the most famous mathematician and inventor in ancient Greece. Archimedes is especially known for his discovery of the relation between the surface and volume of a sphere and its circumscribing cylinder. He is also known for his hydrostatic principle (known as Archimedes’ principle) and a device for raising water, still used in developing countries, known as the Archimedes screw.

Archimedes likely spent some time in Egypt, but spent most of his life in syracuse (hence the Archimedes of Syracuse I'm guessing). He was close with the king at the time, Hieron II. Archimedes played an important role in the defense of Syracuse against the Romans in 213 BCE. He constructed war machines so effective that they delayed the capture of the city. Syracuse did eventually fall at the hands of the Roman general Marcus Claudius Marcellus in the autumn of 212 or spring of 211 BCE, and Archimedes was put to death.

Many details about Archimedes' life have surprisingly survived the years, more than any other ancient scientist, but they are largely anecdotal. He supposedly made two “spheres” that Marcellus took back to Rome—one a star globe and the other a device (the details of which are uncertain) for mechanically representing the motions of the Sun, the Moon, and the planets. The story that he determined the proportion of gold and silver in a wreath made for Hieron by weighing it in water could be true, but the popular claim that he got the idea while taking a bath and leapt up and ran naked through the streets shouting “*Heurēka*!” (“I have found it!”) is likely embellished.

There are nine extant treatises by Archimedes in Greek. *Measurement of the Circle* is a fragment of a longer work in which π (pi), the ratio of the circumference to the diameter of a circle, is shown to lie between the limits of 3 10/71 and 3 1/7. Archimedes’ approach to determining π, which consists of inscribing and circumscribing regular polygons with a large number of sides, was followed by everyone until the development of infinite series expansions in India during the 15th century and in Europe during the 17th century. That work also contains accurate approximations (expressed as ratios of integers) to the square roots of 3 and several large numbers.

I know, lots of technically math stuff, you can thank __Encyclopedia Britannica.__ What might be even more tough to figure out is what your favorite pie is for pi day! I'm a banana cream or maybe rhubarb... I know, they are two totally different pies, but both very good, in my opinion.

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