The series of Indexes is understood, therefore, to begin with the middle of the 16th century (that is, a century after the invention of printing), but from the earliest years of the organised Church, attempts had been made from time to time to protect the faithful against the pernicious influence of heretical writings, by the destruction of the copies and by the punishment of the writers when these were within reach of the strong arm of the Church and when they refused to be convinced of their errors. A number of the editions of the Roman Indexes, as for instance that of 1819, bear as their motto: “Many of them also which used curious arts brought their books together, and burned them before all men” (Acts xix, 19); while on others was printed a head-piece engraved on copper, representing the believers burning their books of magic. The example, however, of these early converts, under the influence of the eloquence of Paul, bringing of their own free will, to be destroyed, books the teachings of which were believed to be incompatible with the doctrines of Christianity, does not constitute a fairly logical precedent for the later practice of the Church in punishing by excommunication and in other ways those who continued to read books condemned as heretical. Throughout the Middle Ages, there are a number of examples of prohibitions, emanating from various authorities, and applying sometimes to single books or individual authors, and sometimes to groups. It is not likely that during the manuscript period, the duplication or reading of the books denounced was seriously affected, except in the immediate locality in which the prohibition was issued. These earlier attempts at censorship possess interest chiefly as indications of the ecclesiastical policy and of the varying standards of different periods and of different places, and also because the titles of the works selected for condemnation were in part utilised by the compilers of the Indexes. A “Directory” of heresy was prepared early in the 16th century by Nicholas Eymeric of Cologne, under the title of _Directorium Inquisitorium_. This was reprinted in Venice in 1607, _cum commentariis Francisci Pegnae_. This Directory was, says Reusch, utilised by Bernard Lutzenburg as the basis for his _Catalogus Haereticorum_,--Catalogue of Heretics,--first issued in 1522. In these two lists have been preserved the names of a number of persons classed as heretics, of whose books there is no record, and who may possibly even never have written anything, or at least never have brought anything into print. The Lutzenburg Catalogue was utilised in the compilation of the Index of Paul IV. After the middle of the 13th century, the papal condemnations of specific books frequently included the specification of names of the examiner or examiners, usually one or more of the cardinals. We have here the beginnings of the body that became later the Congregation of the Index.