Water pressure above the supply pressure was effected by means of a hand worked hydraulic pump, and the force was reckoned by a pressure gauge. This method was so much simpler and easier to work, and also was so much more rapid, that it quickly superseded its predecessor; and now, after forty years’ experience, is still the favourite model, although the machines of to-day contain many improvements not to be found in the original. By all these descending bag chamber models the blocking of the hat is identical. The only difference made is in the amount of pressure, some straws taking more than others without injury. The hat having been properly “roughed out” or “sweated,” that is shaped to its exact size without pressure by hand or machine, and still holding a little steam moisture, is placed accurately in the pan, the outside of the hat to the metal; inside the hat is distributed as evenly as may be a thick felt dummy (to prevent the straw from cutting the bag). If the edge of the crown is very sharp, such as one finds in a man’s boater, a ring of vulcanized rubber or similar material with angles corresponding to the crown edge is placed in position inside the crown before the felt dummy is introduced. The bag chamber is then brought down, securely locked, and the water pressure applied. Different materials require different periods of time to properly set, but while one is setting the operator “roughs out” another hat, so that when the mechanical process on the one is complete, its successor is ready for the operation.