For instance, we possess a series of receipts by Piero Rosselli, acknowledging several disbursements for the plastering of the roof between May 11 and July 27.

We learn from one of these that Granacci was in Rome before June 3; and Michelangelo writes for fine blue colours to a certain Fra Jacopo Gesuato at Florence upon the 13th of May.

All is clearly in the air as yet, and on the point of preparation.

Michelangelo's phrase, "on which I begin work to-day," will have to be interpreted, therefore, in the widest sense, as implying that he was engaging assistants, getting the architectural foundation ready, and procuring a stock of necessary articles.

The whole summer and autumn must have been spent in taking measurements and expanding the elaborate design to the proper scale of working drawings; and if Michelangelo had toiled alone without his Florentine helpers, it would have been impossible for him to have got through with these preliminary labours in so short a space of time.
Michelangelo's method in preparing his Cartoons seems to have been the following.