The story begins with a mysterious parchment which Professor Hardwigg discovers hidden in an ancient runic manuscript from Iceland. The book – and the parchment – was the property of an ancient alchemist. On deciphering the parchment, a terrible secret is revealed: the author claims to have made a journey to the very centre of the earth!
Professor Hardwigg is determined to retrace the steps of this intrepid explorer, and over the objections of his nephew (Harry) he makes plans to depart for Iceland.
The journey to Iceland passes off without any incident. There Professor Hardwigg hires the services of Hans to guide them to the depths of the volcano where the hidden passage is to be found. The climb – and subsequent descent into the crater – is physically exhausting, but Professor Hardwigg is determined to continue the journey. His unwavering belief in the authenticity of the document seems to be confirmed when they find a pedestal at the base of the crater, with markings on it. The shadow of the peak falls upon a central pit, and a passageway is revealed to them that takes them into the very bowels of the earth.
They descend thousands of feet underground, and they come to a place where there are divergent tunnels. Perhaps in haste, they choose to take the eastern tunnel. After traveling for a few days, they come to a dead end – to what resembles a coal mine. Forced to retrace their steps, they run low on supplies and are forced to ration their water. Harry would have preferred to go back at this stage, but Professor Hardwigg overrides his objections. They take the western tunnel, and eventually reach a large opening. But is this the end of their quest – or just the beginning?
This is a tale of adventure in the grandest of traditions. Jules Verne makes full use of the knowledge of geology that was extant during his time. Though Jules Verne theories may be considered to be on the wild side, they are nonetheless plausible. In this, as in his other novels, the author strongly believes that the geographer and the explorer must be one, for the task of exploration cannot be passed on to someone else. And in Professor Hardwigg, the author seems to have found his champion – a person who is willing to stake his very life to further the cause of science.
Harry – who is the eyes and ears of the novelist – is the perfect counter to the strength of character, and the old word charms of Professor Hardwigg. In fact, by his frailty and by his doubting nature, he brings the human element that is so vital to the success of this novel. But this is not a novel that is to be noted for its characterization, or for its dialogue. Its strength rests on the boldness of its premise, and on the vivid descriptions of nature. At times, the author assumes the role of a geologist; it is evident that his purpose is to educate as much as to entertain.
Along with 20,000 Leagues under the Sea, and Voyage to the Moon, this novel is a must read for fans of Jules Verne. There is a similarity in concept and approach to all three novels, for they deal with fantastic journeys - in space, under the sea and under ground.
In these three novels, the author draws heavily on his knowledge of science, and they form the core of the author’s scientific romances. It would be pointless to make comparison with his other works (which may be classified as tales of adventure), but it is these three novels that made his reputation as a prophetic writer ahead of his times.