also began suffering from mounting overpopulation during this period. Population growth was stagnant for the first half of the 17th century due to civil wars and epidemics, but prosperity and internal stability gradually reversed this trend. The introduction of new crops by Europeans such as the potato and peanut allowed an improved food supply as well, so that the total population of China during the 18th century ballooned from 100 million to 300 million people. Soon all available farmland was used up, forcing peasants to work ever-smaller and more intensely worked plots. Emperor Qianlong once bemoaned the country's situation by remarking "The population continues to grow, but the land does not." The only remaining part of the empire that had arable farmland was Manchuria, where the provinces of Jilin and Heilongjiang had been walled off as a Manchu homeland. The emperor decreed for the first time that Han Chinese civilians were forbidden to settle. ) is a palace in the Forbidden City in Beijing, China. It is the largest of the three halls of the Inner Court (the other two being the Hall of Union and the Palace of Earthly Tranquility), located at the northern end of the Forbidden City. During the Qing dynasty, the palace often served as the Emperor's audience hall, where he held council with the Grand Council. History The Beijing–Shanghai railway is composed of three sections. These three sections are some of the earliest railways in China, built before 1910 during the Qing dynasty. The first section is from Beijing to Tianjin, constructed as part of the Imperial Railways of Northern China between 1897 and 1900.