During the Ming Dynasty (1368-1644) this class of literature may be said to have reached its highest development. In the reign of the Emperor Yunglo (1403-1425) was compiled the largest encyclopaedia which has ever seen the light. This gigantic work, which was entitled 'Yunglo ta tien,' consisted of no fewer than 22,877 books, and covered every branch of knowledge possessed by the Chinese. Possibly owing to its immense extent, it was never published; and such volumes as still survive the destroying influences of neglect and decay are yet to be found in manuscript on the shelves of the Imperial Library. Inspired perhaps by the example thus set, the Emperor K'anghi of the present dynasty appointed a commission of scholars to compile a similar work; and after forty years had been consumed in extracting from the past literatures every passage bearing on the 6109 headings which it was the will of K'anghi should be illustrated, the compilers were able to lay before their sovereign a work consisting of 5020 volumes, which they entitled 'Kin L'ing ku kin t'u shu chi ch'eng.' Unlike Yunglo's great work, this one was printed; and though only, as it is said, a hundred copies were issued, some still remain of the original edition. One such copy, complete in every particular, is to be seen at the British Museum. For completeness from a Chinese point of view this work stands out pre-eminently above all others; but owing to the very limited number of copies, it has never superseded the 'Wen hsien t'ung k'ao' by Ma Twanlin, which, though published four hundred years earlier, still holds its own in popular estimation. Much has been written by Chinese authors on scientific subjects, but the substance is remarkable for its extent rather than for its value. In each branch of knowledge they have advanced under foreign influence up to a certain point, and beyond that they have been unable to go. Their knowledge of astronomy, which is of Chaldean origin, is sufficient to enable them to calculate eclipses and to recognize the precession of the equinoxes, but it has left them with confused notions on subjects which are matters of common knowledge among Western people. It is the same in the case of medicine. They understand certain general principles of therapeutics and the use of certain herbs; but their knowledge is purely empirical, and their acquaintance with surgery is of the most elementary kind.