I Google "wedging boy" and found this quote:
"some plate-makers even require their boys to what is called wedge their clay, which is a very laborious process, and consists in lifting large lumps of clays, and throwing them forcibly down on a hard surface, to free it from air and render it more compact. These boys are usually thin and pale, and frequently suffer from pulmonary and digestive diseases. Sickness prevails among them extensively."
Wedging boy does so much more than wedge!