A very large proportion, and, as the years went by, an increasing proportion of the publications of each year consisted of new editions of the earlier issues of the House, but it is to be borne in mind that while, as a rule, these reissues did not call for further publishing initiative or editorial labour they did require an entire resetting of the type, and, therefore, involved a repetition (except perhaps as to the item of illustrations) of the first publishing outlay. The invention of stereotyping and electro-typing, by means of which the form of type once set can be cast, and the plates preserved for use in printing further editions, belongs to a later century. The process of stereotyping was probably first perfected in Paris in 1795, by Firmin Didot. The categories and bibliographies from which I have cited the preceding statistics include not only the books printed and published by the Elzevirs, but the more important of the works which were printed by them for the account of other publishers, and which were, therefore, not issued with their publishing imprint. In the majority of instances, however, the Elzevirs retained, in their hands as booksellers, the agencies for the sale of these books for the Low Countries, for Scandinavia, and frequently for Germany. The lists cited also include the titles of certain books (the number being at best but inconsiderable) which, while published by the Elzevirs, had been printed for them by other printers; and, finally, they include the titles of a number of works which, while not bearing the name of Elzevir, and in fact usually having on their title-page a Lyons or a Cologne imprint, have been identified, through the character of their typography, as coming from one of the Elzevir printing-offices, while, later, it was discovered, chiefly through the investigation of Willems, that for certain classes of books the Elzevirs had made a practice of utilising one of two or three bogus imprints which they had invented for the purpose. By far the larger proportion of the Elzevir publications, probably more than nine-tenths, were printed in Latin. The texts in French were the next in importance, followed, in the order named, by those in Dutch, Greek, Italian, and Arabic. The general character of the literature in the production of which the family had interested itself, is indicated, however roughly, by the titles cited. The books belonged, in the main, to the class that would to-day be described as “heavy literature.” The classics, Greek and Latin, form the larger portion of the list, while there were also groups of important works in Calvinistic Theology, Metaphysics, Medicine, Natural Science, Political Science, History, and Biography. Fiction and legend were represented not at all, and poetry to but an inconsiderable extent. The dramatic list, while not large, was important, including as it did the great productions of Corneille and Molière.