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Newly discovered notes from 15th-century Italy show that the decimal point is actually 150 years older than what historians previously believed. Decimal points may seem basic, but they’re incredibly helpful in math. They divide whole numbers into tenths, hundredths, and thousandths, which makes calculations a lot easier compared to using fractions. Some forms of decimals have been around since the 900s in Damascus and the 1200s in China, as reported by Live Science. A solid system of decimals didn’t become fully established until 1593. This happened when the German mathematician Christopher Clavius included decimals in astronomical work. However, recent studies...

Decimals in a trigonometry table in Tabulae primi mobilis B by Bianchini, written in the 15th century. (Van Brummelen, Hist. Math., 2024) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In 1593, German mathematician Christopher Clavius made a small mark that would change mathematics forever. In a sine table in his treatise on the astrolabe, Astrolabium, he indicated the fractionation of a whole number by writing what has come to be regarded as the very first use of the decimal point. There is, however, just one problem. According to new painstaking research by historian Glen Van Brummelen of Trinity Western University, this wasn't, in fact, its first...

In general, historiography concerning ancient Sicily is overwhelmingly Greco-centric, i.e. focused on its Greek immigrants. Because the indigenous population’s architectonic remains are relatively invisible, whilst those of the Greek immigrants are monumental, the accepted historiography has been that the indigenous population had neither territory, power nor economic resources.It was instead accepted that as soon as the Greeks had established themselves on the island (on the western side in 628 BCE) they colonised and controlled the majority of the Sicilian lowlands, the economy and thus also the indigenous population.This outlook has contributed to an imbalance and a distorted picture of the...

Motya, a small island that covers an area of just under 100 acres (40 hectares), sits off the western coast of Sicily. Bronze and Iron Age populations thrived there due to the abundant supply of fish, salt, fresh water and its protected location within a lagoon, Nigro wrote in the study. In the eighth century B.C., Phoenicians began settling there and integrating with locals, bringing their distinctive West Phoenician culture to the island.Just 100 years later, the settlement had grown into a bustling port city with a trade network stretching across the central and western Mediterranean. This brought Motya into...

Is this Chaucer's astrolabe?Astronomical instruments were probably made after Chaucer's designs, not before.June8, 2007 Philip Ball The British Museum's 'Chaucerian' astrolabe: not really Chaucer's, of course. British Museum Want to see the astrolabe used for astronomical calculations by Geoffrey Chaucer himself? You'll be lucky, says Catherine Eagleton, a curator at the British Museum in London. Several astrolabes have been suggested to have once belonged to Chaucer. The claims are based on the device in question's resemblance to one described by Chaucer in his Treatise on the Astrolabe, written in the late fourteenth century. Perhaps, the claimants argue, the astrolabe they...

I bought this item this evening in a gift shop. I thought it was called an astrolabe. But when I looked up astrolabe on Google it didn't look anything like those. The globe rotates around the arrow shaft. Any one have any ideas?