The Chinese annals, as they have been interpreted by the earned industry of the present age, may be usefully applied to reveal the secret and remote causes of the fall of the Roman empire.

The extensive territory to the north of the great wall was possessed, after the flight of the Huns, by the victorious Sienpi, who were sometimes broken into independent tribes, and sometimes reunited under a supreme chief; till at length, styling themselves _Topa_, or masters of the earth, they acquired a more solid consistence, and a more formidable power.

The Topa soon compelled the pastoral nations of the eastern desert to acknowledge the superiority of their arms; they invaded China in a period of weakness and intestine discord; and these fortunate Tartars, adopting the laws and manners of the vanquished people, founded an Imperial dynasty, which reigned near one hundred and sixty years over the northern provinces of the monarchy.

Some generations before they ascended the throne of China, one of the Topa princes had enlisted in his cavalry a slave of the name of Moko, renowned for his valor, but who was tempted, by the fear of punishment, to desert his standard, and to range the desert at the head of a hundred followers.

This gang of robbers and outlaws swelled into a camp, a tribe, a numerous people, distinguished by the appellation of _Geougen_; and their hereditary chieftains, the posterity of Moko the slave, assumed their rank among the Scythian monarchs.