Winter 1997, Volume 14.1
Cryptography in Artificial Light: Poe's Stories and Nadar's Stills
Michal Sapir is a doctoral candidate in Comparative Literature at New York University. She has published in Modern Fiction Studies and Dance Theatre Journal. Her musical works with the rock band Baby Tooth appeared on the CD Rare Book Room (Personal Favorite Records, 1994). She is currently writing a dissertation which examines issues of gravitation in nineteenth- and twentieth-century literature.
In the beginning of the second half of the nineteenth century, the French photographer Gaspard-Félix Tournachon, or Nadar, as he was widely known, was engaged in several pioneering experiments with the limits of photographic representation. As a portrait photographer he was one of the first to utilize the new medium's vast commercial potential. He was also a champion of experimentation in aeronautical technology, and in 1858 took the first aerial photographs from his hot-air balloon. In 1862 Nadar expanded his experiments into the underground realm. After experimenting in his studio with magnesium as a source of light, he descended into the Paris catacombs to produce the first photographs ever taken on location in artificial light. Two years later, after further refining his technique of electrical lighting, Nadar descended again, this time to photograph the Parisian sewer system.
The beginning of the second half of the nineteenth century also saw the introduction into French intellectual circles of another experimenter with the underworld and the limits of representation, the American poet and short story writer Edgar Allan Poe. Between the years 1852 and 1867 Poe's works were translated into French and published by Charles Baudelaire. Baudelaire's project established Poe's tales of tombs and secret writings as an important source of influence for the emerging new generation of late nineteenth-century French writers.
The subterranean was at the time a privileged locus of meeting for issues of technological progress, knowledge, and representation. As Rosalind Williams explains, the notion that truth is hidden beneath the surface of things was a prevalent epistemological assumption in the nineteenth century, when, following scientific and technological developments, "excavation became a central metaphor for intellectual inquiry" (23).1 However, at the same time, Williams observes, the same scientific and technological developments contributed to the gradual creation of a concept of the subterranean environment as a completely artificial and constructed enclosure (10). Williams's description suggests that in the course of the nineteenth century, the developments in subterranean technology produced a paradoxical attitude towards the accessibility and representability of hidden truth: the closer one got to it by digging deeper under the surface, the farther one was displaced from it by ever-expanding surfaces of artificial mediation.
A similar paradoxical attitude was produced by developments in photographic technology in the same period. Rosalind Krauss observes that early photography was made under the assumption of "the inherent intelligibility of the photographic trace" (42). It assumed that the photograph functions as an indexical trace, supplying "the manifest presence of meaning" (35), with light functioning as "the conduit between the world of sense impression and the world of spirit" (37). But at the same time Krauss finds in early photography a budding ambivalence towards this assumption. She observes that in Nadar's work, for example, photography was also staging its own condition as "a field of physically displaced signs" (46), that is, as consisting of cultural rather than natural signs.
The similarity resides in the spatial dimension of Krauss's observations. As she notes, the photograph was seen as both "a conduit" and "a field": the one a receptacle suggesting purposeful movement in depth, the other a surface suggesting relational, flat movement. This ambivalence has to do with the function of the photograph as text, as emerges from Krauss's discussion of a chapter in Henry Talbot's book The Pencil of Nature. In this chapter, entitled "A Scene in a Library," Talbot juxtaposes a text and a photograph which seem strangely unconnected. In the text he speculates on the possibility of photographs taken with "invisible rays" (50) revealing the activities that occur within a "darkened chamber" (51). The photograph, in turn, shows two loaded bookshelves in a library (49). For Krauss, this juxtaposition demonstrates a conception of the photograph as a conduit towards a spiritual meaning beyond objective appearances: photography will penetrate not only the darkness of the chamber, but also the obscure regions of the human mind (42). But this juxtaposition of photograph and text can also be read as pointing to the limitations of photography as a form of mediation. As Krauss points out, "as the container of written language, the book is the place of residence of wholly cultural, as opposed to natural, signs" (41). Thus, the book's conductivity, as in turn its photograph's conductivity, are put into question. Both stop short at the surface of signs—a flat field of words on paper, "volume" flattened out into volumes in the library—without accessing the signified. In the photograph as well as in the paragraph, the stereometrical space of "the real" becomes a flat "field of physically displaced signs."
Nadar's project of photographing the catacombs and the sewers of Paris can be seen as an attempt to put Talbot's speculations into practice. He descended into the "darkened chamber" par excellence—the burial cave, the crypt. Like Talbot's imaginary photographer, he attempted through the use of photographic technology to expand the limits of display and put the secret occurrences within on exhibit. But, again like in Talbot's example, Nadar's results were only a displacement of the alleged truth of the crypt onto a flat, culturally-constructed textual surface. As such, as we will see, Nadar's photography of crypts—his cryptophotography—behaved just like Poe's writing of crypts—his cryptography. When truth is assumed to be hidden in the depth, the story and the still behave in a similar way: instead of illuminating a secret space, they only manage to put on display another secret, another piece of (encoded) writing. As I will suggest later, this refutation of both writing and photography as vehicles to a hidden truth was contemporaneous with the emergence in the late nineteenth century of new and different kinds of media and of a different notion about the space of truth.
Let us first examine Nadar's subterranean project. For a Parisian in the nineteenth century, the descent into the catacombs was a descent into the highly revered realm of the dead. According to Philippe Ariès, the building of the catacombs in the eighteenth century was emblematic of the Parisians' growing indifference towards the dead, an indifference which culminated in the destruction of all the city's cemeteries and the transportation of the remains to underground depositories (499500). By the late nineteenth century, however, the Parisians had developed what Ariès calls "the cult of tombs" (542); "in one century the cult of the dead has become the great popular religion of France" (543). This obsession with the space of death was also expressed in the great popularity of deathbed photography at the time.
Nadar, however, "rarely accepted commissions for...deathbed pictures," in spite of their growing popularity (Gosling 13). For someone who had always displayed a keen sense of business, and who was, moreover, known especially for his portrait photography, this seems odd. Perhaps Nadar was somehow aware of the problem of photography which Roland Barthes describes in Camera Lucida as the presence of "flat death" (92). The deathbed photographs of the poetess Marceline Desbordes-Valmore (1859) and of Nadar's friend Victor Hugo (1885), two of the very few exceptions to Nadar's avoidance of the subject, can testify, perhaps, to some of the frustration involved in such an undertaking. In both, bright light floods the frame in an almost desperate attempt at revelation, and the camera approaches the body from the side and headwards, as if an intimate friend were sitting at the bedside of the dying person to hear the last words or even to touch the body. But in both pictures there is nonetheless an atmosphere of mute and secretive remoteness, an opaqueness and a failure of disclosure. Behind the resistant façade there is no available recess, only the blank flipside of the flat photographic print.
And so Nadar turned his attention to what lies behind the façade, to the underworld. In 1862 and 1864 he embarked on his two projects, photographing first the Parisian catacombs and then the city's elaborate sewers. In his memoirs from 1900, Quand j'étais photographe, he recollects these two projects in the chapter "Paris Souterrain." He begins with the catacombs. Here is how he describes his expectations from the project: "The underground world opens an infinite field of operations, no less interesting than the tellural surface. We are going to penetrate, reveal the arcana of the most profound and secret caverns…. The catacombs of Paris…have their confidences to share with us" (14546). This passage demonstrates how Nadar's attempt to reveal secrets in depth is ultimately blocked by the impervious two-dimensionality of representation, by the "infinite field of operations." After all, Nadar himself admits that the catacombs are pictorially boring, and that their appeal exists only within language: "The picturesque quickly exhausts itself here, the aspects are not varied…. This mysterious word—catacombs—excites curiosity on its own accord…. A few steps in these undergrounds and the curiosity is soon satisfied" (13738). And so, actually, the catacombs are the precise opposite of death, to which everybody goes but from which no one returns to disclose its secrets. The catacombs, on the contrary, are "a place where everybody wants to go and to where no one returns" (138).
As it happens, it is really his own technological light-operations, and not the darkness of the death realm, that interest Nadar. He opens the chapter with a fictional dramatization in which a Parisian lady is introduced by him to the "dangerous" and "shadowy" underworld passages: "You don't know the catacombs, madame; allow me to conduct you there," he says (124). Note that it is his mundanely human hand that will serve as conduit here, not the mystical index-finger of light. In the description that follows, the salient characteristic of the underground world is its chaotic nature. Hierarchical order is disrupted: the text is heaped with various words signifying "heap" or "mess"; the body—social or physical—is subject to "the egalitarian confusion of death" and is "disintegrated, dispersed" (129); endless lists enumerate names ("Condés and Contis, Soyecourt and Vendome, Le Rochefoucauld, Créqui, Rohan, Montmorency, Vilars, Blacas…Durand, Legrand, Petit, Lemaitre, Berger, Lenoir or Leblanc" ), titles ("the cardinal Dubois, Marguerite de Bourgogne with the provost Marcel, Perrault, the architect storyteller, the Marshal of Ancre..." ) and body parts ("ribs, vertebra, sternums, wrists, tarsi, metacarpus and metatarsus, phalanges, etc." ). It all boils down to what Nadar calls "the nothingness of the human thing" (129) and a "conclusive and universal abandon" (137). But the visitors, the excursionists, as he calls them, are not going to be implicated in this chaos: "counted at the entrance to be recounted at the exit, they only dare within perfect security by the restrained itinerary that is conferred to them in the ossuary" (126). The dead themselves, the visitors are assured by a Latin inscription on the door, repose "beyond these boundaries" (128).
And so, to be recounted again, or to be made visible, the contents of the catacombs must be transformed from their chaotic heaps and stuffings into the orderly flatness of a time-table: "here is the light, the sun, life, which chase behind us like a painful, even tedious dream, the memory of this funereal excursion. We, now, redescend in order to work" (138, emphasis mine). Nadar embarks on the first ever subterranean attempt at photography in artificial light. How artificial is this artificial light? Well, the first attempts back at his studio in 1858 involved about fifty Bunsen batteries, and produced plates which were "harsh, with clashing effects, opaque blacks and without details." The pupils, in particular, were a problem: "either extinguished by an excess of clarity, or brutally pricked, like two nails" (141). To perfect the results, he needed a second fire-box of softened light, excavating the shadowed parts. The solution was "using white screens as reflectors, and finally a double play of large mirrors reverberating intermittently the luminous fire-box on the shadowed parts" (14142). With such an echoing game of reflectors and mirrors we begin to see, indeed, the infinite field of operations on which the project takes place. But that isn't all. When the operation moved to its actual location, the narrowness of the subterranean passages forced a large part of the equipment to be left outside, on the street level. Long cables were passed underground through small shafts or man-holes. The removal of the generator caused major communication problems as there was a considerable lapse of time between the giving of orders and their reception. This often imposed an exaggerated development of the conductor wires, and at each displacement Nadar had to feel empirically his time of exposure. Again, it is important to note how the whole notion of the conduit has been displaced from a bridge between the world of the senses and the world of the spirit into a chart-line from one world of the senses to another.
But the extent to which the project of artificial light really involved artificiality becomes even clearer in the following passage:
I've judged it good to animate some of these aspects with a person, less from a picturesque point of view than in order to indicate the scale of proportions, a precaution very often upsettingly neglected by explorers. For the eighteen minutes of exposure-time (fr. pose), it was difficult to obtain the absolute, inorganic immobility from a human being. I tried to get round the difficulty by using manikins, which I dressed in working-clothes and arranged in the mise en scène; this detail did not complicate our job. (156)
But it sure did complicate the representational status of the photographs thus obtained. After all, this is a perfect example of the Orphean plight, as it is understood by Blanchot: in the Greek myth Orpheus is allowed to lead his dead wife Eurydice back from Hades into the light of day, provided he never turns back to look at her while they are still in the underworld. For Blanchot Orpheus is the artist, whose work is to bring death—the profoundly obscure point toward which art and desire tend—into human perception. But Orpheus can only give this point form, shape, and reality in the day, by turning away from its essential darkness, in other words, by misrepresenting it: "Orpheus is capable of everything…except of looking at the center of night in the night" (171). Nadar, according to this reading, is a modern Orpheus: like him, he went down to the underworld to retrieve a being into the human realm. But the being, once brought to light, became a dummy. All Nadar can bring back from the underworld by using artificial light is the truth of the artificiality of this light. His photographs, calibrated to fit the human scale of proportions, remain only aspects, exterior façades, mise-en-scènes of representation. The thing-represented itself remains outside of the picture, whose flipside is, again, only a blank surface.
Recoiling, Nadar suddenly cuts short his account of the catacombs project in the middle of "Paris Souterrain." "We are going to pass on the catacombs," he says, and turns instead to "recognize the admirable human labor in the sewer system" (144). Here, as well, there is use of artificial light and artificially dug man-holes. And, interestingly enough, the sewers are all about conduits: canals, rails, wagons, pipes, tubes, etc. But these are the conduits of human technology, and in their circular network they lead nowhere but to their own starting point, the Grand Collecteur which gathers all its arteries to dispense the water right back into the Parisian drain system. In this system, proper measures are carefully taken: poisonous odors, traffic collisions, and putrid floodings are duly prevented. And in the rapid descent that Nadar's narrative stages into the filthy, fluid, monstrous depth of the earth, "the black rendez-vous with the immense nothingness" is averted at the last minute, as "we finally retreat" (152). Nadar remains safe on the game-board of his "field of operations." Nadar spent three consecutive months in the catacombs and the sewers of Paris. Then after producing one hundred plates, he stopped, "with regret in spite of everything, for the work was not yet altogether complete" (157). Why did he stop? He says that urgent matters called him back to his studio on the boulevard des Capucines, but mainly that in the catacombs he was given to the outer-limits of resignation and arrived at the farthest ends of his patience. The experience was obviously frustrating, but Nadar, even as late as 1900, is not able to formulate for himself the causes of his frustration.
Let us now turn from Nadar's stills to the other experimenter with tombs and cryptography, Edgar Allan Poe. In Poe's stories there is a constant slippage between the spatial sense of "crypt"—a dark enclosure—and the linguistic sense—a code. Everything in his tales is enclosed within one kind of receptacle or another: a bottle, a box, a chamber, a coffin, a vault, a building. The recurring pattern is that of the mystery of the locked room, or, if you will, the darkened chamber—the camera obscura. A case is to be opened. Or, rather, a case is to be solved. And herein, precisely, lies the slippage, between the spatial case and the narrational case, between the set of coordinates and the field of affairs. In "The Cask of Amontillado," for example, Fortunato is lured by the promise of a fictive cask to his real encasement in the narrator's family vaults. This "real" spatial emplotment itself, however, only lures the reader to the termination of the fictive plot drawn up on paper by Poe himself. "The Facts in the Case of M. Valdemar," to take another example, deals, like many other tales, with the Orphean paradox of bringing the space of death into language. In the Greek myth, once taken into the world of the living, all that remained from Eurydice was the flat fact of her ineffable death. Likewise, Valdemar seems to utter the most impossible utterance of all—"I am dead." But it is also the only possible thing for him to say in his case. When the darkened case of the tomb becomes the illuminated case of language, we can only get flat death: "I am dead."
Similarly, as Derrida has observed, in Poe "everything begins 'in' a library" (qtd. in Rosenheim 389). Derrida puts the word "in" in quotation marks because, like in Talbot's photograph, the library easily slips from a camera obscura"our first meeting was at an obscure library"—to the flat pages of a book—"the same very rare and very remarkable volume brought us into closer communion" (Selected Tales 108). The same movement occurs in the very title of the story, "Murders in the Rue Morgue." The murders occur "in" Morgue street, which is a spatial place of storage for dead bodies, but also an archive of literature and press cut-outs. And then there is "The Purloined Letter," which takes place in a "little back library, or book-closet, au troisième" (201), that is, on the third story of Dupin's building, or, perhaps, in the third story in the Dupin series. For, eventually, everything also ends "in" a library: there are no actual three-dimensional cases in Poe's tales, but only upper cases and lower cases, letters written on the page.
Shawn Rosenheim links this process of flattening to Poe's interest in cryptography: "the narrative form of the detective stories...emerges indirectly out of the understanding of signification Poe first articulated in the essays on 'secret writing'" (376). According to Rosenheim, Poe creates in the stories an artificially flattened world in which the detective can find one single, verifiable meaning because nothing is hidden behind the surface, and because a strict indexical relationship has been pre-established between appearances and behaviors (382). Consequently, Poe's letters have no depth—only two sides. They become dead letters, which reach no destination, attesting only to the fact of their own existence. Finally, they reveal "Poe's reluctant realization that every decoding is another encoding, and that the crypt of the letter can't be penetrated in an attempt to extract its immanent meaning" (381).
Consequently, in its emphasis on the materiality of language, its figuratively, its multiplicity of forms and meaning and its endless potential for puns, Poe's work, like Nadar's photography as it is described by Krauss, "stages…its own condition as a field of physically displaced signs." In "The Man of the Crowd" the narrator is engaged in a project not unlike that of Nadar's. He attempts to illuminate, via acute observation and professional acumen, a certain subterranean realm. By the artificial light of the gas-lamps he follows the subject of his investigation, only to find himself circulating and retracing his steps in an urban labyrinth. Back at his starting point in front of the D—— Hotel (which is, by the way, the residence of the Minister, Dupin's cunning rival, in "The Purloined Letter"), he finally realizes that, like some books which don't permit themselves to be read, "there are some secrets which do not permit themselves to be told… And thus the essence of all crime is undivulged" (97). Dupin, the great cryptographer, remains duped.
What then, is the connection between Nadar's crypt-photography and Poe's cryptography? Friedrich Kittler writes in "Gramophone, Film, Typewriter" about the media revolution that came about in the late nineteenth century. This revolution was prompted by the double spearhead of, on the one hand, the invention of the typewriter, and, on the other hand, the invention of cinema and of the phonograph. The typewriter terminally severed writing's alleged connection to a sensu ality beyond the symbolic (113). One could no longer subscribe to the 1800s' Romantic supposition that the book is a material conduit to "the realm of the dead beyond the senses" (107). Instead, in the 1880s Mallarmé was able to state that "literature does not mean anything but that it consists of twenty-six letters" (114). Cinematography and phonography, in turn, with their ability to record time indexically, took over the task of representing that realm of the dead which was now outside the grid of the symbolic (110).
As Kittler observes, this waning of the grammatological monopoly over what constitutes the real was a direct consequence of the same invention that made artificial lighting possible: "Electricity itself has brought this to an end" (110). He, however, leaves photography out of this particular picture. Indexical, but not able to store time, it had consequences, he writes, only in the æsthetic domain and not in terms of the constitution of the real (104). But if photography cannot be said to have been fighting alongside the cinema and the phonograph in this media revolution, the study of Nadar and Poe may have revealed its affiliation, conversely, with the typewriter's ranks. The dates seem right—the typewriter was introduced to Europe in 1865 (Kittler 113). One might say that photography (especially with the help of artificial light), although not really heralding the representation capacities of the later media, nevertheless facilitated their conquest by undermining its own claims to an authenticity beyond the limitations of writing. In Nadar's experiments we may be witnessing photography staging its own failure to be anything but a coded, grammatological writing, and thus underlining the lack of the element of time in its formula. In a dialectical movement, photography can thus also be seen to undermine the monopoly of writing by exposing its self-referential, coded nature.
Nadar's and Poe's cryptography in artificial light hints at the new conception of the space of truth that the new time-sensitive media will both depend on and make possible. The enigma of Nadar's exhibits lies in the depth: between the lines of the visual information, the spatial crypt remains a blind spot, unavailable to display. His solution, on the other hand, what he does put on display, emerges not from some dark profundity, but from the intermittent reverberation of light in a system of white screens and large mirrors. The puzzle of Poe's cryptograms also consists of such a system of echoes: concocted by human ingenuity, it can therefore be resolved by human ingenuity ("Secret Writing" 116). But "the mental features discoursed of as the analytical are, in themselves, but little susceptible of analysis" (Selected Tales 105); in the dark recesses of the crypt, the enigma of the spirits still persists.
Carlo Ginzburg suggests a way of conceptualizing the changing ideas about enigmas and solutions in the late nineteenth century. His formulation seems to reinstall the assumption of depth and conductivity. Ginzburg defines the epistemological model of "symptomatology," examples of which he finds in Morelli's art connoisseurship, Freud's psychoanalysis and Sherlock Holmes's detection methods. In this model, "marginal and irrelevant details…provide the key to a deeper reality, inaccessible by other methods" (87). The efficacy of such a key depends on the assumption of depth, and of the existence of a conduit between the surface and the hidden recesses: "Reality is opaque; but there are certain points—clues, symptoms—which allow us to decipher it" (109). But this assumption of depth becomes suspect in Ginzburg's text itself when, in the course of one page, the volume becomes a book, and the portentous points become deflated ink dots: from "deciphering," the symptomatological practice becomes that of "reading," and, finally, turns into "the invention of writing 'the book of nature'" (89). It seems that Ginzburg's detective does not realize that the traces he follows are only his own footsteps.
What emerges from Nadar and Poe, conversely, is a conception of a time-governed, provisional truth, a truth which is not exposed in its authentic depth, but is rather invented and read into the surface relationships between horizontally-expanding signifiers.2 The terms of Kittler's discussion suggest that he too associates the end of writing's rule with a spatial movement from three-dimensional volume to a multivalent field of operations. In terms that recall Nadar's intermittent reverberation of light he describes Alan Turing, the Enigma man, who in 1950 invented his "universal discrete machine," the conceptual basis for all computers. Later, Konrad Zuse, another computer pioneer, was to echo Poe's assertion in "Secret Writing" when he said: "With this form of brain it has to be theoretically possible to solve all puzzles that can be mechanically dealt with, regardless of the time required" (qtd. in Kittler 117).
Furthermore, although Kittler insists that the new media of cinematography and phonography are able to store noise, residue, and waste—dimensions of the real which cannot be symbolically encoded in writing—he admits that nonetheless they too end up proving that "the content of each medium is another medium" (111). It seems that they too cannot quite escape Nadar's predicament in the catacombs: "From the real, nothing more can be brought into the daylight than what Lacan had presupposed in its being given—nothing" (114). Perhaps this is so because, to some extent at least, these media are still a form of writing, as is suggested by their names (104), as well as by the words Kittler himself uses to describe their emergence: "something had to stop not writing itself" (103).
The crucial difference, according to Kittler, is that the new media of the 1880s and 90s constitute a different kind of writing, a "writing for machines" (115), which takes the passing of time into account. The added dimension here is not the third, but the fourth: this writing expands not vertically in space, but laterally, in time. The media revolution, Kittler says, levelled all messages to the surface (or interface) of information, and left spirit, as it were, out of the picture (115). Volume has become first a typed page and a photograph, and then a recording tape and a movie screen: the flat but fluid, labyrinthine network of "integrated circuits" (117). Such mechanism is already hinted at in Nadar's and Poe's cryptographies. If media, as Kittler writes, "are always already flight apparatuses into the other world" (112), then these cryptographies can be seen as early contributors to the making of the latest modern version: the flat flight-simulator.
1 Williams mentions Victor Hugo's Les Misérables as a typical example for this kind of epistemological framework. In the novel the setting of crucial events in the Parisian sewers serves as a metaphor for the author's belief that the foundational truth of the visible façade of cultural and historical events lies in their obscure and hidden interiors (4647). Hugo was a close friend and political ally of Nadar's; Les Misérables was published in 1862, the same year Nadar first went underground.
2 A similar relinquishment of depth in favor of surface is described by Linda Nochlin in her essay on the representation of death in the second half of the nineteenth century. Following the "isolation of the fact of death from a context of transcendental significance or value" (64), artists concentrated on "the sheer phenomenology of dying" (60), because "the reduction of the vertical significance of death requires an expansion of its horizontal circumstantiality" (66).
Ariès, Philippe. The Hour of Our Death. Trans. Helen Weaver. 1981. New York: Oxford UP, 1991.
Barthes, Roland. Camera Lucida: Reflections on Photography. Trans. Richard Howard. New York: Noonday, 1981.
Blanchot, Maurice. "Orpheus's Gaze." The Space of Literature. Trans. Ann Smock. 1955. Lincoln: U of Nebraska P, 1982. 17176.
Ginzburg, Carlo. "Morelli, Freud, and Sherlock Holmes: Clues and Scientific Method." The Sign of Three: Supin, Holmes, Peirce. Eds. Umberto Eco and Thomas A. Sebeok. Bloomington: Indiana UP, 1988. 81-118.
Gosling, Nigel. Nader. London: Secker & Warburg, 1976.
Kittler, Friedrich. "Gramophone, Film, Typerwriter." October 41 (1987): 101-18.
Krauss, Rosalind. "Tracing Nadar." October 5 (1978): 29-47.
Nadar. Quand j'etais photographe. 1900. Pref. and notes Jean-Francois Bory. Paris: Seuil, 1994.
Nochlin, Linda "Death in the Mid-Nineteenth Century." Realism. Style and Civilization. Harmondsworth: Penguin, 1971. 57-101.
Poe, Edgar Allan. "A Few Words on Secret Writing." Essays and Miscellanies. Ed. James A. Harrison. 2nd ed. New York: AMS P, 1979. 114-149.
____. Complete Tales and Poems. New York: Vintage, 1975
____. Selected Tales. Ed. Julian Symons. Oxford: Oxford UP, 1980.
Rosenheim, Shawn. "The King of 'Secret Readers': Edgar Poe, Cryptography, and the Origins of the Detective Story." ELH 6 (1989): 375-400.
Talbot, William Henry Fox. The Pencil of Nature. A facsimile of the 1844-1846 edition. New York: Da Capo, 1969
Williams, Rosalind. Notes on the Underground: An Essay on Technology, Society, and the Imagination. Cambridge, MA:MIT P, 1990.