The NPM has the largest collection of the fa-lang-ts\'ai porcelains from the Ch\'ien-lung reign, which contains more then five hundred pieces. This collection can be divided into two categories, namely, fa-lang-ts\'ai porcelains and yang-ts\'ai porcelains. All of them are masterpieces of unprecedented quality made by the Ch\'ing dynastic court, and they were emperor Ch\'ien-lung\'s favorites. This illustrated catalogue mainly contains yang-ts\'ai porcelains; but it also has fa-lang-ts\'ai porcelains for the reader to compare with the yang-ts\'ai porcelains. Photos in this catalogue are extremely realistic and splendid.