“A complication of unfortunate accidents has, up to this moment, prevented me from answering your kind letter of last July. My poor mother has frequently, during the summer, been in extreme danger of death. My own chest, too, has more than once been threatened, and is still far from strong. All this, however, does not save me from a feeling of remorse at having been so tardy towards one whose scientific reputation, as well as his courteous manners, entitle him to so much consideration. My labour, as you say, is not yet over. The task, as I had indeed anticipated from the beginning, has proved an exceedingly difficult one. As an evidence of the difficulty I need only mention that the celebrated Giuseppe Assemani, in the similar work which he undertook,[336] has made numerous mistakes, having in one instance given no less than six different titles to seven copies of the same work. This great orientalist, with all his learning, could not command the time necessary for so troublesome a task as that of ascertaining the titles and authors of books which are quite unknown and often imperfect. For my part, I resolved from the beginning that I would not, willingly at least, add to the other deficiencies of which I am conscious, that of haste and insufficient time. _Nam quo minus ingenio possum, subsidio mihi diligentiam comparavi_; and the condescension of his Serene Highness has in the end relieved me, by extending until April the time allowed for the completion of the task. The grammarians, rhetoricians, poets, prosodians, logicians, and theologians, have taken up all my time hitherto; in the course of the next two months, I hope to complete the enumeration of the other authors; and then I shall at last fulfil my promise of sending you, when occasion serves, whatever I think may interest you.” De Rossi, in his letter, to which this is a reply, had put some questions regarding the contents of the octavo edition of D’Herbelot’s _Bibliothèque Orientale_, the preface of which had contained a promise of many important improvements. Mezzofanti, referring to these promised additions, goes on to say, “In the articles which I have compared, I have only found a few verbal corrections. But in the preface, we are promised additional articles, drawn from the narratives of travellers subsequent to D’Herbelot. From this promise you will be able to infer what information you may expect to derive from the edition, and whether it is likely to be useful for your purpose. I have not yet received the supplement, which was to contain certain articles which have been postponed for reasons explained in the preface. Perhaps the reason of its not having been printed, may be, that the articles in question, being of use to orientalists alone, may be found by them in the former editions.