The improvement continued until the middle of the eighteenth century. About the time of the French Revolution there began a continuous decline, slow at first and then gathering speed. The European works on China offer various reasons for this: the many foreign wars (to which we shall refer later) of the emperor, known by the name of his ruling period, Ch'ien-lung, his craze for building, and the irruption of the Europeans into Chinese trade. In the eighteenth century the court surrounded itself with great splendour, and countless palaces and other luxurious buildings were erected, but it must be borne in mind that so great an empire as the China of that day possessed very considerable financial strength, and could support this luxury. The wars were certainly not inexpensive, as they took place along the Russian frontier and entailed expenditure on the transport of reinforcements and supplies; the wars against Turkestan and Tibet were carried on with relatively small forces. This expenditure should not have been beyond the resources of an ordered budget. Interestingly enough, the period between 1640 and 1840 belongs to those periods for which almost no significant work in the field of internal social and economic developments has been made; Western scholars have been too much interested in the impact of Western economy and culture or in the military events. Chinese scholars thus far have shown a prejudice against the Manchu dynasty and were mainly interested in the study of anti-Manchu movements and the downfall of the dynasty. On the other hand, the documentary material for this period is extremely extensive, and many years of work are necessary to reach any general conclusions even in one single field. The following remarks should, therefore, be taken as very tentative and preliminary, and they are, naturally, fragmentary. [Illustration: (Chart) POPULATION GROWTH OF CHINA] [Illustration: 14 Aborigines of South China, of the 'Black Miao' tribe, at a festival. China-ink drawing of the eighteenth century. _Collection of the Museum für Völkerkunde, Berlin. No. ID_ 8756, 68.] [Illustration: 15 Pavilion on the 'Coal Hill' at Peking, in which the last Ming emperor committed suicide. _Photo Eberhard_.] The decline of the Manchu dynasty began at a time when the European trade was still insignificant, and not as late as after 1842, when China had had to submit to the foreign Capitulations. These cannot have been the true cause of the decline. Above all, the decline was not so noticeable in the state of the Exchequer as in a general impoverishment of China. The number of really wealthy persons among the gentry diminished, but the middle class, that is to say the people who had education but little or no money and property, grew steadily in number. One of the deeper reasons for the decline of the Manchu dynasty seems to lie in the enormous increase in the population. Here are a few Chinese statistics: