 The deckle could not make a perfect seal against the screen at the edges and the paper slurry would seep under, creating a rough edge to the paper.The deckle edge could be trimmed off, but this extra step would add to the cost of the book.Beginning in the early 1800s with the invention of the Fourdrinier machine, paper was produced in long rolls and the deckle edge became mostly obsolete; although there was some deckle on the ends of the rolls, it was cut off, and the individual sheets cut out from the roll would have no deckle in any case.