We have now declared the aim of our work and the route which we propose to follow. In order to increase our chances of success, I have sought and obtained the collaboration of M. Charles Chipiez, whose special knowledge is well calculated to neutralise my own deficiencies. To his _Histoire critique des Origines et de la Formation des Ordres grecques_, was awarded, in 1877, one of the highest prizes of the Académie des Inscriptions, and in the Salons of 1878 and 1879 he confirmed his double reputation as a skilful draughtsman and a learned theorist; his _Essais de Restoration d'un Temple grecque hypèthre, et des tours à étages de la Chaldée_, was much noticed and discussed by connoisseurs. It would not be fitting, however, to praise it here. I must confine myself to saying how fortunate I am in having obtained a help which I have found more helpful, more single-minded, more complete, than I had dared to hope for. In all that has to do with architecture, I have not written a line until after consulting M. Chipiez upon all technical points. He has also taken an active part in the revision of the text of certain chapters. As for the plates and illustrations in the text, we have together chosen the objects to be represented, and M. Chipiez, as a professional man and able draughtsman, has personally superintended the execution of the drawings. It remains for me to explain the _rôle_ which we have assigned to our illustrations. VI. In the single edition of his great work which appeared during his own lifetime, Winckelmann inserted but a small number of illustrations, and those for ornament rather than for instruction. One of his translators, M. Huber, tells us that their execution gave great dissatisfaction to the author.[35] In our days, on the other hand, those who undertake a work of this kind make use of the great progress which has taken place in engraving and typography, to insert numerous figures in their text, to which they offer an indispensable and animated commentary. Without their help many descriptions and observations might remain unnecessarily obscure and doubtful. When forms are to be defined and compared, mere words, in whatever language spoken or written, can never suffice. [35] _Histoire de l'Art_; Huber's preface to his translation, p. xxxii.