Drawing Techniques: a Guide
Process: Pouncing  
Artists also transferred images by pouncing, that is, by pricking the contour lines of a drawing, placing it against the destination surface, and then rubbing a fine powder through the holes. This method was useful for transferring finished drawings from one sheet to another, cartoons to the final panel or plaster, or finished studies for prints the the printing plate. The powder was usually made of ground pumice, which adhered to wet plaster, but not to paper, and charcoal dust was also used.
  Italian, Paduan School, 15th Century, Study of a Roman Relief Depicting the Suovetaurilia, Private Collection