BENVENUTO CELLINI, in his Due trattati dell' orificeria e delta scultura: 'When you have made
a satisfactory model you draw the principal views of your statue on [the sides of] the stone; and mind
it be well drawn, for if not you may miscut your block. The best method I ever saw was that which
Michelangelo used, which is to draw the front view and then carve it round, as if you wanted to make
a relief, and then to cut deeper and more freely.'
'To succeed with a figure in marble the art requires a good craftsman first to set up a little model about two palms high (c. 18 inches). In this model he carefully thinks out the pose, making his figure :
draped or nude, as the case may be. After this he makes a second model much more carefully than the smaller. If however he be pressed for time, or if his patron needs the work in a hurry, it will suffice if he complete his big model in the manner of a good sketch. . . . True it is that many able artists have gone straight for the marble with all the fury of the chisel, preferring to work merely from a small and well designed model; however, they have been less satisfied with their final piece than they would have been if working from a full-scale model. This is noticeable in the case of Donatello, who was indeed a great man, and even with the wondrous Michelangelo, who worked in both ways. But it is well known that when his fine genius felt the insufficiency of small models, he set to work with the greatest humility to make models of the size of his marble. And such models I have seen with my own eyes in the saci»Bty of San Lorenzo.'
Cellini also discusses the material for these large clay models: 'Take such clay as is used by the ordnance-makers for their moulds . . . Let it dry and sift it carefully through a rather coarse sieve in order to get rid of any pebbles or bits of root . . . Then you mix it with cloth frayings, about half as much of the latter as you have clay . . . When the clay and the cloth frayings are mixed and bathed with water to the consistency of a dough, you beat the mixture up well with a stout iron rod about two fingers thick.'
Vasari on the technique for full-scale models in his 'Introduction to Sculpture', prefixed to hisLives of the Artists, 1550: 'When the small models in wax or clay are finished, the artist sets himself to make a full-scale model in the size of the actual figure which he intends to execute in marble ... In order that this large model should support itself and not crack, the artist must mix cloth frayings or horse hair with the clay; and this will make the clay tough and not liable to split. The armature is made of