Note 174 — Chapter IV · (XI.)

Vasari actually says that it must be put ‘al fuoco’ ‘to the fire,’ but it is clear that he does not mean that heat is at once to be applied to it. If this were done the wax would all be melted off the core too soon, before it was covered by the outer skin. It is only when the wax has been securely enclosed between the core and the outer skin that heat is needed to melt it away and leave its place free for the molten metal.