between Rome and Macedon begins, with Rome encouraging its Greek allies, such as Attalus I of Pergamon, to attack the forces of Philip V of Macedon. 210 BC: Qin Shi Huang dies while on a trip to the far eastern reaches of his empire in an attempt to procure an elixir of immortality from Taoist magicians. 200s BC 208 BC: Zhao Tuo (Triệu Đà) defeats the Vietnamese king An Dương Vương. 207 BC: Triệu dynasty of Viet Nam is inaugurated. 206 BC: Qin dynasty falls after men from all over China revolts, attacking officials, raising armies, and declaring themselves kings of seized territories. 206 BC – 202 BC: Civil war of the Chu-Han contention in China. 205 BC: the Cretan War (205–200 BC) begins between Macedonia and its allies against the Greek polis of Rhodes and its allies, resulting in a Rhodian victory. 202 BC: Romans defeat Carthage, ending the Second Punic War. Carthage's territories are reduced to some of its North African holdings, and crippling reparations are demanded by Rome. 202 BC: In East Asia, the Chu-Han contention comes to a close, Xiang Yu commits suicide, and the Han dynasty of China is founded (202 BC–220 AD) by Liu Bang. 200 BC: The Second Macedonian War between Rome and Macedon begins. Indian traders regularly visit Arabia. Scythians occupy Sogdiana, in modern-day Uzbekistan. Inventions, discoveries, introductions Eratosthenes accurately calculates Earth's circumference and introduces the sieve of Eratosthenes, an algorithm for identifying prime numbers. Weiqi, known as Go in English, well-established in China, and may date back to the 2nd millennium BC. Crucible steel was first produced in Southern India. Canopus stele of Ptolemy III implements the leap year in Egypt. Leap year not formally recognized until Caesar in 55 BC. First Roman sundial (293 BC). Toe stirrup finds its earliest manifestation in India. Water screw invented by Archimedes. The Euclidean algorithm, the oldest algorithm still in use today, introduced by Euclid. Invention of the hydraulis (the precursor to the Pipe organ) by Ctesibius, a Greek engineer working in Alexandria. Zinc mining was first smelted from zinc ore in India Emperor Gaozu of Han China discovers an elaborate mechanical puppet theater in the treasury of the previous ruler Qin Shi Huang. The enormous Du Jiang Yan Irrigation System of China is engineered and constructed by Li Bing (李冰) in 256 BC. Great Stupa, Sanchi, Madhya Pradesh, India, Maurya period, is founded