The Discovery and Decipherment of Saknussemm’s Parchment is the turning point that transforms an obscure scholarly riddle into the governing plan of the expedition. When Henry notices Latin words showing through on the parchment’s reverse, he realizes that the message must be read from right to left. Its decoded instruction directs an audacious traveler into the crater of Sneffels before the Kalends of July, promising that the route will reach the Earth’s centre. The solution gives Professor Hardwigg the evidence he needs to act, but the journey that follows also exposes the tension between a written claim, scientific theory, and what the travelers observe underground.

The Puzzle and the Breakthrough

Henry’s first encounter with the cryptogram is a struggle rather than a flash of immediate insight. The jumble seems to combine incompatible words and idioms; he searches for a connection among ice, anger, cruelty, sacred wood, change, mother, and sea, without finding a coherent sentence. The Icelandic setting suggests that the first and last terms might evoke a sea of ice, but that partial possibility does not explain the rest. Frustration becomes physical: Henry’s eyes ache from staring at the parchment, the letters seem to dance, and he fans himself mechanically with the document.

That accidental movement changes the problem. As the ink has passed through the paper, the reverse reveals recognizable Latin words, including craterem and terrestre. Henry understands that these are not stray clues but evidence that the text has been approached from the wrong direction. The solution is to read the document backward. He recognizes that Professor Hardwigg had dictated the cryptogram correctly, though neither of them had yet found the method that made it intelligible. The discovery therefore joins close attention to chance: the crucial evidence was on the parchment all along, but its orientation had concealed it.

Decoding the Instruction

Henry’s excitement gives way to the practical task of reading the recovered message. He is so moved that he trembles and initially struggles to make sense of it; after drawing a breath, he prepares to read. When he explains that the sentence makes sense from right to left, Professor Hardwigg at first responds angrily that it means nothing. The reversal produces a sudden recognition: Hardwigg exclaims over Saknussemm’s ingenuity, takes the document, and reads the decoded text for himself.

The Latin inscription names the crater of Yocul of Sneffels, the shadow of Scartaris, and the deadline of the Kalends of July. Its translation commands the traveler to descend into the crater before that date and promises arrival at the centre of the Earth; it ends with the author’s assertion that he did it, signed Arne Saknussemm. The message is more than a general claim that a route exists. It specifies a location, a condition tied to the shadow, and a time limit, turning the cryptogram into a set of instructions that can guide the expedition’s approach to the volcano.

Hardwigg’s response makes clear how much the decoded document changes. He leaps from the ground, rushes around the room, knocks over furniture, and scatters books before collapsing, exhausted, into his armchair. His reaction is both comic and consequential: the professor who had been absorbed in an intellectual puzzle now treats its solution as a warrant for action. The parchment’s decipherment supplies the expedition with its objective and lends urgency to the preparations that follow.

From Written Claim to Expedition

The decoded message does not settle whether Saknussemm actually reached the Earth’s centre. Henry accepts that Saknussemm identified an entrance, but considers it madness to suppose that he, or anyone else, completed the journey. He grounds his doubt in scientific teaching, arguing that the increase of heat with depth would make descent impossible: according to the calculation he cites, temperature rises by one degree for every seventy feet. Hardwigg rejects the authority of theory as a reason to abandon the document. The disagreement establishes a continuing conflict between the parchment’s testimony and accepted accounts of the Earth’s interior.

The inscription’s route also makes the physical setting part of its proof. Later, Hardwigg interprets the behavior of the volcanic steam vents as evidence that no eruption is imminent. He reasons that approaching eruptions would make the vents more active, while an eruption would cause them to disappear as elastic fluids sought refuge inside the crater. If the steam remains habitual and the atmospheric conditions show neither heavy pressure nor dead calm, he concludes, there is no immediate danger. His confidence translates scientific observation into permission to proceed, echoing the earlier decision to treat Saknussemm’s written directions as actionable evidence.

Underground, Henry continues to compare what they encounter with what their theories predict. He points to fossil forms on the passage walls and holds up an almost perfect shell, asking Hardwigg to draw a conclusion from it. Hardwigg identifies it as a trilobite shell and tries to restrict what it proves; Henry’s insistence that the discovery demands interpretation keeps the disagreement between observation and the professor’s composure alive. The shell does not itself decode the parchment, but it extends the episode’s central question: how much should direct evidence force a revision of established expectations?

The same question becomes sharper when the travelers estimate that they are sixteen leagues, or fifty miles, below the surface. Henry argues that this is the extreme limit science allows for the thickness of the Earth’s crust, and calculates that known laws of increasing heat should imply a temperature of fifteen hundred degrees Réaumur. He considers whether refractory lava, a poor conductor of heat, might account for the discrepancy, and notes that the hot-water jet supports his explanation. Rather than prolong the argument, he says he will take the facts as they are and asks to draw a definite conclusion from Hardwigg’s calculations. The expedition thus advances through a sequence of tests: Saknussemm’s message prompts the descent, while the journey forces both men to confront observations their prior models do not comfortably explain.

Narrative and Thematic Significance

The decipherment is structured as a recognition scene. The document first appears to promise meaning while resisting every attempt to read it; the reverse view then reveals that the apparent disorder results from a simple but concealed instruction about direction. The solution is both intellectual and material: Henry does not discover a new passage of text but changes how he looks at the same parchment. Its significance lies in the shift from unreadable signs to a route that can be acted upon.

The scene also establishes distinct styles of judgment between Henry and Professor Hardwigg. Henry’s discovery depends on patient attention and, finally, accident; his later objections appeal to calculations, geological limits, and physical observations. Hardwigg is willing to let Saknussemm’s assertion outweigh conventional theory, and later uses his own interpretation of volcanic signs to justify continuing. Neither the parchment nor the scientific arguments remove uncertainty. Instead, the decoded instructions set the expedition in motion, and the underground evidence repeatedly makes the travelers negotiate the distance between what a text promises, what theory permits, and what they see for themselves.