A short dictionary entry from Knight's American Mechanical Dictionary describing machines for sizing (shrinking or planking) felt hat-bodies to the proper size and form. It explains a trough machine with a corrugated elastic bed and semicircular rocker that kneads the body in hot water, and a table-type machine with reciprocating table and oscillating platen, with jets of hot water or steam. Two line drawings (Figs. 2425 and 2426) illustrate the machines.