A Journey to the Centre of the Earth (Voyage au centre de la Terre), also translated as A Journey to the Interior of the Earth, is a classic 1864 science fiction novel by Jules Verne. The story involves a professor who leads his nephew and hired guide down a volcano in Iceland to the "centre of the Earth". They encounter many adventures, including prehistoric animals and natural hazards, eventually coming to the surface again in southern Italy. The living organisms they meet reflects the geological time; just as the rock layers become older and older the deeper one gets, the animals get more and more ancient the closer the characters come to the center. From a scientific point of view, this story has not aged quite as well as other Verne stories, since most of his ideas about what the interior of the Earth contains have since been proven wrong. However, a redeeming point to the story is Verne's own belief, told within the novel from the viewpoint of a character, that the inside of the Earth does indeed differ from that which the characters encounter. One of Verne's main ideas with his stories was also to educate the readers, and by placing the different extinct creatures the characters meet in their correct geological era, he is able to show how the world looked like millions of years ago, stretching from the ice age to the dinosaurs.
The book was inspired by Charles Lyell's Geological Evidences of the Antiquity of Man of 1863. By that time geologists had abandoned a literal biblical account and it was generally thought that the end of the last glacial period marked the first appearance of humanity, but Lyell drew on new findings to put the origin of human beings much further back in the deep geological past. Lyell's book also influenced Louis Figuier's 1867 second edition of La Terre avant le déluge which included dramatic illustrations of savage men and women wearing animal skins and wielding stone axes, in place of the Garden of Eden shown in the 1863 edition.
Professor Liedenbrock decides to lock everyone in the house and force himself and the others (Axel, and the maid, Martha) to go without food until he cracks the code. Axel discovers the answer when fanning himself with the deciphered text: Liedenbrock's decipherment was correct, and only needs to be read backwards to reveal sentences written in rough Latin. Axel decides to keep the secret hidden from Professor Liedenbrock, but after two days without food, he cannot stand the hunger and reveals the secret to his uncle. Liedenbrock translates the note, which is revealed to be a medieval note written by the (fictional) Icelandic alchemist Arne Saknussemm, who claims to have discovered a passage to the centre of the Earth via Snæfellsjökull in Iceland. The deciphered message reads:
In slightly better Latin, with errors emended:
which, when translated into English, reads:
Professor Liedenbrock is a man of astonishing impatience, and departs for Iceland immediately, taking his reluctant nephew with him. Axel repeatedly tries to reason with him, explaining his fears of descending into a volcano and putting forward various scientific theories as to why the journey is impossible, but fails to make Professor Liedenbrock see his point of view. After a rapid journey via Lübeck and Copenhagen, they arrive in Reykjavík, where the two procure the services of Hans Bjelke (a Danish speaking eiderdown Icelander hunter) as their guide, and travel overland to the base of the volcano. In late June they reach the volcano, which has three craters. According to Saknussemm's message, the passage to the centre of the Earth is through the one crater that is touched by the shadow of a nearby mountain peak at noon. However, the text also states that this is only true during the last days of June. During the next few days, with July rapidly approaching, the weather is too cloudy for any shadows. Axel silently rejoices, hoping this will force his uncle to give up the project and return home. On the last day, though, the sun comes out and the mountain peak shows the correct crater to take.
After descending into this crater, the three travelers set off into the bowels of the Earth, encountering many strange phenomena and great dangers, including a chamber filled with combustible gas, and steep-sided wells around the "path". After taking a wrong turn, they run out of water and Axel almost dies, but Hans taps into a neighboring subterranean river. Liedenbrock and Axel name the resulting stream the "Hansbach" in his honor and the three are saved. At another point, Axel becomes separated from the others and is lost several miles from them. Luckily, a strange acoustic phenomenon allows him to communicate with them from some miles away, and is soon reunited. After descending many miles, following the course of the Hansbach, they reach an unimaginably vast cavern. This underground world is lit by electrically charged gas at the ceiling, and is filled with a very deep subterranean ocean, surrounded by a rocky coastline covered in petrified trees and giant mushrooms. The travelers build a raft out of trees and set sail. The Professor names this sea as the Liedenbrock Sea. Whilst on the water, they see several prehistoric creatures such as an Ichthyosaurus, which fights and kills a Plesiosaurus. After the battle between the monsters, the party comes across an island with a huge geyser, which Liedenbrock names "Axel Island". A lightning storm again threatens to destroy the raft and its passengers, but instead throws them onto the coastline. This part of the coast, Axel discovers, is alive with prehistoric plant and animal life forms, including giant insects and a herd of mastodons. On a beach covered with bones, Axel discovers an oversized human skull. Axel and Liedenbrock venture some way into the prehistoric forest, where Professor Liedenbrock points out, in a shaky voice, a prehistoric human, more than twelve feet in height, leaning against a tree watching a herd of mastodons. Axel cannot be sure if he has really seen the man or not, and he and Professor Liedenbrock debate whether or not a proto-human civilization actually exists so far underground. The three wonder if the creature is a man-like ape, or an ape-like man. The sighting of the creature is considered the scariest part of the story, and the explorers have decided that it is better not to alert it of their presence as they figure it may be hostile.
The travelers continue to explore the coastline, and find a passageway marked by Saknussemm as the way ahead. However, it is blocked by what appears to be a recent cave-in and the three despair at being unable to hack their way through the granite wall. The adventurers proceed to blast the rock with gun cotton and paddle out to sea to escape the blast, but the explosion is larger than they expected and they are swept away as the sea rushes into the large open gap in the ground. After spending hours being swept along at lightning speeds by the water, the raft ends up inside a large chimney filling with water and magma. Terrified, the three are rushed upwards, through stifling heat, and are ejected onto the surface from a side-vent of a volcano. When they regain consciousness, they discover that they have been thrown out of Stromboli, at the southern tip of Italy. They return to Hamburg to great acclaim - Professor Liedenbrock is hailed as one of the great scientists of history, Axel marries his sweetheart Graüben, and Hans eventually returns to his peaceful life in Iceland. The Professor has some regret that their journey was cut short.
At the very end of the book, Axel and Liedenbrock realize why their compass was behaving strangely after their journey on the raft. They realize that the needle was pointing the wrong way after being struck by an electric fireball which nearly destroyed the raft.