Making the Plates
William Blake's original relief-etched copper plates, with which he printed his illuminated books such as the Songs of Innocence and of Experience, The Marriage of Heaven and Hell and Europe a Prophecy, were lost in the nineteenth century. The only evidence that has survived that shows how his revolutionary method was carried out, of etching his text and design together in relief so that both could be printed at the same time, from the same plate, in his rolling press, is a single fragment of a cancelled plate from America a Prophecy, now in the Lessing J. Rosenwald Collection of the National Gallery of Art, Washington, D.C. This fragment shows clearly how Blake etched his plates, in two stages, to a total depth of 0.12 mm., making it possible to re-create the relief-etched copper plates of the illuminated books in the same way; and to print impressions from them that are all but indistinguishable from Blake’s originals.
To re-create plates from Blake’s illuminated books exact-size photo negatives of the rare original monochrome impressions have been used, together with those of posthumous impressions printed in the 1830s by Frederick Tatham, before the plates were lost. Tatham was a friend of William and Catherine Blake in their last years and, when Catherine died, the plates came into his possession. Tatham had not been trained as a printmaker and mistakenly printed the plates on dry paper; skilled printmakers normally dampen and blot their papers before printing to open the interstices, with the result that after printing, when the impressions are pressed and dried, the paper (and the image that has been printed) shrinks by a few millimeters. Tatham’s impressions thus provide the precise dimensions of the original plates, needed to re-create Blake’s original relief-etched copper plates exactly to size.
Once exact-size photo negatives have been made they are modified to eliminate printing flaws in the original impressions – such as poor inking, smudging and spattering – in order to establish the clearest and most complete example. The amended negative is then transferred to the copper plate using a photographic transfer process. But before etching, further often meticulous refinements are required, either by scraping out unwanted details using an etching needle, or adding missing ones using a fine pencil brush and stop-out varnish. Exactly following Blake’s practice, each plate is then etched in two stages to the same shallow depths as the America fragment. After an initial bite, the mordant is poured away and the text and design checked for signs of underbiting, with stop-out varnish applied to any vulnerable areas. The plate is then bitten again.
Inks and Papers
The same attention to historical accuracy has been given to preparing inks, inking and wiping the plates, selecting papers and printing. Inks are specially mixed with linseed oil before each printing session using combinations of the same historic dry pigments that we know Blake used: bone black, vermillion, madder lake, gamboge, yellow ochre, Prussian blue and lead sulfate (obtained from Kremer Pigmente of Germany suppliers of historic pigments to museums and galleries for restoration). The printed impressions are then compared with the colours of ink Blake used to print his impressions, and mixed and printed again until the inks match.
Blake inked his relief-etched plates using a leather-covered dauber similar to, but much smaller than, a letterpress printer’s ink ball (ink rollers were not invented until near the end of Blake’s life). To create the same mottled effects a dauber or ball is used like Blake’s to build up the ink in mist-thin layers on the delicate relief surfaces. Once the plates have been inked, any of the etched shallows that have been inadvertently flicked with ink or touched by the dauber or ball must be carefully wiped.
Inking and wiping a plate can take up to two hours with the larger plates of America and Europe, and half an hour or more for a plate from the Songs. This may help to explain the care and especially the time that Blake needed to prepare his relief-etched plates for printing, as described by John Jackson and W. A. Chatto in A Treatise on Wood Engraving, Historical and Practical (1839). In spite of these efforts some instances of tiny driblets of ink and traces of wiping may be found, an inevitable result of inking and wiping the plates as Blake did, and a characteristic of many of his printed impressions.
The papers used for printing are selected from a collection of old hand-made laid and wove papers that in colour, texture, and weight compare with the papers that Blake used to print his illuminated books and separate prints, “the most beautiful wove papers that could be procured,” as Blake wrote in his prospectus of 10 October 1793. The papers are torn to the same size as the handful of copies of the illuminated books that have survived with the sheets left untrimmed, as Blake issued them to his customers in paper wrappers (for example, in the Berg Collection of the New York Public Library). For the smaller plates, like those of the Songs of Innocence and of Experience and The Marriage of Heaven and Hell, they measure 280 x 190 mm. For printing the larger plates, like those of America a Prophecy, Europe a Prophecy and Jerusalem, 390 x 280 mm.
The Printing Process
Because Blake etched his copper plates of text and design in relief, leaving the printing surface standing proud, he was able to print from these raised surfaces using very little pressure. This allowed him to print on the verso of the same sheet, with the result that when the sheets were bound together the printed impressions faced each other as in a conventional book. Blake later printed on only one side of the leaf, the practice that is followed here.
As a result of using very little pressure in printing the impression, by increasing it, a second impression can be printed from the residue of ink remaining on the relief surfaces. To increase the pressure, sheets of paper, or additional thin wool blankets, are added, before passing the plate and new sheet of paper to be printed between the rollers. The increased pressure creates a highly attractive bas-relief of the contours of the relief-etched copper plate imprinted in the fabric of the paper.
As each plate has been carefully inked by hand it is impossible to duplicate the same layering and grainy texture of the ink when the plate is again prepared for printing, with the result that each impression is distinct, and, within each set of impressions printed from the same mix of ink, subtle differences in tone and texture can occur. Thus, like Blake’s originals, no two impressions are the same. Each is unique.