Plate 41, as per the Met Museum website has the following dimensions
Dimensions: sheet: 16 5/16 x 11 1/4 in. (41.5 x 28.5 cm)
image: 9 5/8 x 7 7/8 in. (24.5 x 20 cm)
The same image dimensions are given for Plate 28 in their collection although the sheet size differs slightly.
Dimensions: sheet: 16 5/16 x 11 9/16 in. (41.5 x 29.3 cm)
image: 9 5/8 x 7 7/8 in. (24.5 x 20 cm)
As Dore drew the images himself directly onto the woodblock for an engraver to do the actual cutting, this should be the size of the originals.
Gustave Doré is most well known for his wood engraved illustrations. Yet very few of these were engraved by Doré himself. In the 19th century, before the invention of photographic reproduction, books and newspapers were printed using metal type. In order to include images along with type, printers had to have drawings or paintings reproduced on “type high” wood blocks so that they could be included with type on their printing presses. Translating a painting into a printable block was simply a part of the commercial reproduction process. Engravers were considered tradesmen, not artists. Ironically, though Doré is most remembered for his iconic wood engraved illustrations, Doré himself often complained that the engraving process did not do justice to his images. He would sometimes photograph his drawings, executed directly on the wood block, in order to preserve the original, before the engraver translated it into a print ready version