About 1550 the wooden screw was replaced by iron.
Twenty years later, innovators added a double-hinged chase consisting of a frisket, a piece of parchment cut out to expose only the actual text itself and so to prevent ink spotting the nonprinted areas of the paper.
Next came the tympan, a layer of a soft, thick fabric to improve the regularity of the pressure despite irregularities in the height of the type.
Around 1620 Willem Janszoon Blaeu in Amsterdam added a counterweight to the pressure bar which made the platen rise automatically; this was the "Dutch press", a copy of which was to be the first press introduced into North America, by Stephen Daye at Cambridge, Massachusetts in 1638. That press began printing in early 1639.
About 1790 an English scientist and inventor William Nicholson, devised a method of inking using a leather covered cylinder (later in conjunction with a composition of gelatin, glue, and molasses). This was the first introduction of rotary movement into the printing process.
