This print is probably the most abstract and architecturally irrationally structured scene in the Carceri series. It is also unique in that it passes through all the revised states of the series with relatively little alteration. Its generic title derives from the nearest of two wheel-like downward curving forms that dominate the upper three-fifths of the scene. It is unlikely that Piranesi intended these forms to represent a wheel, as they lack both hub and spokes. In fact, this "giant wheel" is more like an enormous, truncated circular frame, a sort of freestanding oculus displaced to a vertical position where it ambiguously hovers in space. Within this segmented form is glimpsed a precariously suspended timbered scaffolding partially obscured by smoke or steam. In the lower central section of the print, two masonry arches abut a massive post and lintel masonry door frame.

In the left foreground are three figures, one seated, one standing, and one kneeling. The standing figure presses down on the head of the kneeling one with his right arm. Another triad of figures appears in the lower right corner, and in the background a solitary figure stands atop a sketchily indicated stairway. More figures, lost in a web of scratched lines, lean over a balustrade in the background. Above the central doorway there is a cylindrical platform to which is affixed a spiked pillar. A crouching figure is pinioned to the left of the pillar, and, to the right, a standing figure turns toward an eerily indeterminate shape, which seems to crouch on the curve of the "giant wheel." Nearby a recumbent figure dangles over the edge of the "giant wheel," and next to this figure are two more who struggle to support a cross-like wooden form.

Of all the etchings in the Carceri series, this one most fully retains the immediacy and spontaneity of a pen and ink sketch. The sense of drawing, the evanescent quality of the sketch, and the suggestion of form imprecisely defined--of the non finito so greatly appreciated by connoisseurs of the period--permeate the work. Indeed, it is hard to believe that the intervention of the printer's art took place, that this is not actually a swiftly executed drawing in pen and ink. Malcolm Campbell, from Art in Rome in the Eighteenth Century (2000), cat. 414, pp. 573-574.

BIBLIOGRAPHY Focillon, Henri. Giovanni-Battista Piranesi: Essai de catalogue raisonné de son oeuvre. Paris: Librairie Renouard,1918, no. 32.
Hind, Arthur M. Giovanni Battista Piranesi: A Critical Study with a List of His Published Works and Detailed Catalogues of the Prisons and the Views of Rome. London: The Cotswold Gallery, 1922, "The Prisons," no. 9.
Robison, Andrew. Piranesi, Early Architectural Fantasies: a Catalogue Raisonné of the Etchings. Washington, D.C.: National Gallery of Art; Chicago and London: The University of Chicago Press, 1986, no. 35 ii/viii.
Wilton-Ely, John. Giovanni Battista Piranesi: The Complete Etchings. 2 vols. San Francisco: Alan Wofsy Fine Arts, 1994, vol. 1, no. 34.

Only a master mason's son schooled in Venetian theatrical set design could have conjured up this giant oculus set at an angle above a monolithic doorway seen from below, as if from the audience. Shortly after settling in Rome in 1747, Giovanni Battista Piranesi etched fourteen copperplates of imaginary prisons filled with just such stagecraft effects of smoke and shadow. He went on to win international acclaim with antiquarian and architect alike by etching a series of hefty tomes, interleaving prints of ancient ruins with images of Baroque churches and palazzos. Piranesi later made a second edition of the prison etchings, drastically darkening them to conform to his archaeologist's eye, grown accustomed to the gloom of subterranean excavations pierced by shafts of sunlight. The Museum's complete first edition of the prison images is one of the exceedingly rare early printings, issued before Piranesi had time to make corrections on the title plate to his Roman publisher's name, Bouchard, which he had given a Venetian twist, spelling it by ear as Buzard. John Ittmann, from Philadelphia Museum of Art: Handbook of the Collections (1995), p. 220.