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The Cooperative Publishing Union, in beginning its work with the present publication, feels it a duty to express its gratitude to all those who, by assisting with advice and aid, allowed it to undertake its first endeavor with confidence.
The benevolence and encouragement of His Excellency Deputy F. Mariotti, Undersecretary of State for Public Instruction, who was pleased to suggest the printing of this Treatise; the kind condescension of the illustrious Senator M. Tabarrini, who, by composing the elaborate Preface, allowed it to be presented to the public under the auspices of his renowned name; the zealous, friendly, and affectionate work of the Honorable Deputy A. Maffi, who facilitated the task undertaken by the Cooperative; the welcome services rendered by the Honorable Deputy V. Armirotti; the precious suggestions of the most distinguished gentlemen G. Bobbio, G. Chiarini, G. Cugnoni, R. De Cesare, A. Fantoni, G. Mazzoni, D. Melegari, G. Mestica, and E. Monaci; the promise of the Honorable Senator A. Messedaglia, of the Honorable Deputies R. Bonghi and F. Martini, and of the most distinguished gentlemen C. Calisse, I. Giorgi, D. Gnoli, E. Novelli, G. Tomassetti, and O. Tommasini, to contribute to the works that will follow this one, constitute a collection of support that makes the Cooperative Publishing Union hesitant The publishers are expressing a modest concern that their work might not fully live up to the high level of support they received. as to whether it has responded adequately to them.
And the gratitude of the publishers is also due to the firm of G. C. Sansoni of Florence, which, through Professor G. Biagi and Mr. G. Ceccherini, contributed to making this volume even more valuable by authorizing the inclusion of the Life of Da Vinci This refers to the biography of Leonardo written by Giorgio Vasari in the 16th century. taken from its highly accurate edition of Vasari's works, accompanied by new notes and the Commentary of Professor G. Milanesi Gaetano Milanesi (1813–1895) was a famous art historian known for his definitive annotated editions of Vasari..
To all these collaborators, the Cooperative Publishing Union gives thanks.
Rome, January 1890.