But the influence of copper plate work was strong, and some skillful but misguided woodcut craftsmen tried to obtain some degree of its richness. French artists from about 1720, notably Jean M. Papillon, produced cuts so delicate that their printing became a problem (see fig. 6). Jackson, who had worked with the French artist in Paris, condemned his efforts to turn the woodcut into a tonal medium through the creation of numerous delicate lines because such effects were impossible to print. Jackson[14] is quoted in the _Enquiry_: In 1728 Mr. _Pappillon_ began his small _Paris_ Almanack, wherein is placed Cuts (done on Wood) allusive to each Month, with the Signs of the Zodiack, in such a Minute Stile, that he seems to forget in that Work the Impossibility of printing it in a Press with any Clearness ... But alas! His father and M. _le Seur_ [also woodcutters] had examined Impression and its Process, and saw how careful the Ancients were to keep a proper Distance between their Lines and hatched Works, so as to produce a clean Impression ... I saw the Almanack in a horrid Condition before I left _Paris_, the Signs of the Zodiack wore like a Blotch, notwithstanding the utmost Care and Diligence the Printer used to take up very little Ink to keep them clean. It is clear that too thin a strip of white between black lines was not suitable for printing in the first half of the 18th century. But when Bewick's cuts after 1790 are examined we can see many white lines thinner than a hair. Obviously something had happened to permit him a flexibility not granted to earlier workers on wood. Bewick's whole craft depended upon his ability to control white lines of varying thickness. Why was he able to do this, and why could it be done without trouble by others after him? Early paper, as already mentioned, had a ribbed grain because it was made on a hand mould in which wires were closely laid in one direction, but with enough space between to allow the water in the paper pulp to drain through. Crossing wires, set some distance apart, held them together. Each wire, however, made a slight impression in the finished paper, the result being a surface with minute ripples. The surface of this laid paper presented irregularities even after the glazing operation, done with hammers before about 1720 and with wooden rollers up to about 1825.[15]