Example of Pouncing in Sistine Chapel.You can still see the pounced holes.
All the drawings for the Sistine Chapel were burnt in 1518. Michelangelo
died in 1564.
Pouncing is a technique
where you transfer the image of the cartoon (drawing) to the plaster wall:
1) You prick the cartoon with holes on the main lines.
2) Tack the paper to the fresh plastered wall and then
taps the holes with a porous bag of charcoal.