this work I pretend not, I repeat it, to form an accomplished connoisseur in painting: my object is to facilitate and expedite the acquisition of such knowledge. The history of painting is the basis of connoisseurship; by combining it, I supersede the necessity of referring to many books; by abbreviating it I save the time and labour of the student; and by arranging it in a proper manner on every occasion, I present him with the subject ready prepared and developed before him. It remains, in the last place, that I should give some account of myself; of the criticisms that I, who am not an artist, have ventured to pass upon each painter: and, indeed, if the professors of the art had as much leisure and experience in writing as they have ability, every author might resign to them the field. The propriety of technical terms, the abilities of artists, and the selection of specimens of art, are usually better understood, even by an indifferent artist, than by the learned connoisseur: but since those occupied in painting have not sufficient leisure to write, others, assisted by them, may be permitted to undertake the office.[18] By the mutual assistance which the painter has afforded to the man of letters, and the man of letters to the artist, the history of painting has been greatly advanced. The merits of the best painters are already so ably discussed that a modern historian can treat the subject advantageously. The criticisms I most regard are those that come directly from professors of the art. We meet with few from the pen of Raphael, of Titian, of Poussin, and of other great masters; such as exist, however, I regard as most precious, and deserving the most careful preservation; for, in general, those who can best perform can likewise judge the best. Vasari, Lomazzo, Passeri, Ridolfi, Boschini, Zanotti, and Crespi, require, perhaps, to be narrowly watched in some passages where they allowed themselves to be surprised by a spirit of party: but, on the whole, they have an undoubted right to dictate to us, because they were themselves painters. Bellori, Baldinucci, Count Malvasia, Count Tassi, and similar writers, hold an inferior rank; but are not wholly destitute of authority: for though mere _dilettanti_, they have collected both the opinions of professors and of the public. This will at present suffice, with regard to the historians of the art: we shall notice each of them particularly under the school which he has described.