what did they use to build the great wall of china
Great Wall of China Before the use of bricks, the Great Wall was mainly built from rammed earth, stones, and wood. During the Ming, however, bricks were heavily used in many areas of the wall, as were materials such as tiles, lime, and stone. The size and weight of the bricks made them easier to work with than earth and stone, so construction quickened. Additionally, bricks could bear more weight and endure better than rammed earth. Stone can hold under its own weight better than brick, but is more difficult to use. Consequently, stones cut in rectangular shapes were used for the foundation, inner and outer brims, and gateways of the wall. Battlements line the uppermost portion of the vast majority of the wall, with defensive gaps a little over 30 cm (12 in) tall, and about 23 cm (9.1 in) wide. From the parapets, guards could survey the surrounding land.[56] Communication between the army units along the length of the Great Wall, including the ability to call reinforcements and warn garrisons of enemy movements, was of high importance. Signal towers were built upon hill tops or other high points along the wall for their visibility. Wooden gates could be used as a trap against those going through. Barracks, stables, and armories were built near the wall's inner surface.[56]
History of the Great Wall of China One of the first mentions of a wall built against northern invaders is found in a poem, dated from the seventh century BC, recorded in the Classic of Poetry. The poem tells of a king, now identified as King Xuan (r.  827 – 782 BC) of the Western Zhou dynasty (1046 – 771 BC), who commanded General Nan Zhong (南仲) to build a wall in the northern regions to fend off the Xianyun.[22] The Xianyun, whose base of power was in the Ordos region, were regarded as part of the charioteering Rong tribes,[23] and their attacks aimed at the early Zhou capital region of Haojing were probably the reason for King Xuan's response.[22] Nan Zhong's campaign was recorded as a great victory. However, only a few years later in 771 BC another branch of the Rong people, the Quanrong, responded to a summons by the renegade Marquess of Shen by over-running the Zhou defences and laying waste to the capital. The cataclysmic event killed King Xuan's successor King You (795–771 BC), forced the court to move the capital east to Chengzhou (成周, later known as Luoyang) a year later, and thus ushered in the Eastern Zhou dynasty (770–256 BC). Most importantly, the fall of Western Zhou redistributed power to the states that had acknowledged Zhou's nominal rulership. The rule of the Eastern Zhou dynasty was marked by bloody interstate anarchy. With smaller states being annexed and larger states waging constant war upon one another, many rulers came to feel the need to erect walls to protect their borders. Of the earliest textual reference to such a wall was the State of Chu's wall of 656 BC, 1,400 metres (4,600 feet) of which were excavated in southern Henan province in the modern era. However the Chu border fortifications consisted of many individual mountain fortresses; they do not constitute to a lengthy, single wall. The State of Qi also had fortified borders up by the 7th century BC, and the extant portions in Shandong province had been christened the Great Wall of Qi. The State of Wei built two walls, the western one completed in 361 BC and the eastern in 356 BC, with the extant western wall found in Hancheng, Shaanxi.[24] Even non-Chinese peoples built walls, such as the Di state of Zhongshan and the Yiqu Rong, whose walls were intended to defend against the State of Qin.[25]
History of the Great Wall of China One of the first mentions of a wall built against northern invaders is found in a poem, dated from the seventh century BC, recorded in the Classic of Poetry. The poem tells of a king, now identified as King Xuan (r.  827 – 782 BC) of the Western Zhou dynasty (1046 – 771 BC), who commanded General Nan Zhong (南仲) to build a wall in the northern regions to fend off the Xianyun.[22] The Xianyun, whose base of power was in the Ordos region, were regarded as part of the charioteering Rong tribes,[23] and their attacks aimed at the early Zhou capital region of Haojing were probably the reason for King Xuan's response.[22] Nan Zhong's campaign was recorded as a great victory. However, only a few years later in 771 BC another branch of the Rong people, the Quanrong, responded to a summons by the renegade Marquess of Shen by over-running the Zhou defences and laying waste to the capital. The cataclysmic event killed King Xuan's successor King You (795–771 BC), forced the court to move the capital east to Chengzhou (成周, later known as Luoyang) a year later, and thus ushered in the Eastern Zhou dynasty (770–256 BC). Most importantly, the fall of Western Zhou redistributed power to the states that had acknowledged Zhou's nominal rulership. The rule of the Eastern Zhou dynasty was marked by bloody interstate anarchy. With smaller states being annexed and larger states waging constant war upon one another, many rulers came to feel the need to erect walls to protect their borders. Of the earliest textual reference to such a wall was the State of Chu's wall of 656 BC, 1,400 metres (4,600 feet) of which were excavated in southern Henan province in the modern era. The State of Qi also had fortified borders up by the 7th century BC, and the extant portions in Shandong province had been christened the Great Wall of Qi. The State of Wei built two walls, the western one completed in 361 BC and the eastern in 356 BC, with the extant western wall found in Hancheng, Shaanxi.[24] Even non-Chinese peoples built walls, such as the Di state of Zhongshan and the Yiqu Rong (義渠), whose walls were intended to defend against the State of Qin.[25]
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