Rouquayrol–Denayrouze device

The Rouquayrol–Denayrouze device is a diving apparatus that Captain Nemo has refined for his own special uses, enabling him and his crew to explore the ocean depths for extended periods without suffering organic disorders. It is a central piece of technology that makes the novel's many underwater excursions possible, from the hunting trip in the Crespo Island forests to the exploration of the lost continent of Atlantis.

Design and Function

The device consists of a tank built from heavy sheet iron in which air is stored under a pressure of fifty atmospheres. This tank is fastened to the back by means of straps, like a soldier's knapsack. Its top part forms a box where the air is regulated by a bellows mechanism and can be released only at its proper tension. In the standard Rouquayrol device, two india-rubber hoses leave this box and feed to a kind of tent that imprisons the operator's nose and mouth; one hose is for the entrance of air to be inhaled, the other for the exit of air to be exhaled, and the tongue closes off the former or the latter depending on the breather's needs. However, because Captain Nemo faces considerable pressures at the bottom of the sea, he has modified the device to enclose his head in a copper sphere, like those found on standard diving suits, and the two hoses for inhalation and exhalation now feed to that sphere. The tank on his diving equipment can supply breathable air for nine or ten hours.

Integration with Other Equipment

The Rouquayrol–Denayrouze device is used in conjunction with the Ruhmkorff device, which provides light. The Ruhmkorff device is fastened to the belt and consists of a Bunsen battery that is activated with sodium. An induction coil gathers the electricity generated and directs it to a specially designed lantern containing a glass spiral with a residue of carbon dioxide gas, which becomes luminous and gives off a continuous whitish light. Thus provided for, the diver can both breathe and see. The diving suits themselves are made from seamless india rubber and are expressly designed to bear considerable pressures. They consist of a jacket and pants, with the pants ending in bulky footwear adorned with heavy lead soles. The fabric of the jacket is reinforced with copper mail that shields the chest, protects it from the water's pressure, and allows the lungs to function freely. The sleeves end in supple gloves that do not impede hand movements.

Use in Underwater Excursions

The device is used in several key underwater excursions. During the first underwater stroll on the plains of the Pacific, Professor Aronnax, Conseil, and Captain Nemo use the device to walk on the seafloor at a depth of ten meters. The air supply is sufficient for the duration of the walk, which lasts several hours. During the hunting expedition in the Crespo Island forests, the device allows the party to descend to a depth of 150 meters, ninety meters below the limit that nature had previously set on man's underwater excursions. The device is also used during the exploration of the Atlantis continent, where Captain Nemo and Professor Aronnax walk for hours at a depth of 300 meters. During the imprisonment in the ice at the South Pole, the device becomes a lifeline, as the crew use it to dig a trench through the ice while the air inside the Nautilus grows foul. The device's air tanks are used to supply fresh oxygen to the workmen, and it is the device that ultimately saves the lives of the three protagonists when Ned Land and Conseil sacrifice their own air to revive the suffocating Professor Aronnax.

Narrative Significance

The Rouquayrol–Denayrouze device is a symbol of Captain Nemo's technological mastery and his ability to create a self-sufficient world beneath the waves. It allows the characters to explore the ocean depths in a way that was previously impossible, and it is a key element in the novel's exploration of the relationship between humanity and the sea. The device also serves as a plot device, enabling the characters to survive in extreme conditions and to witness wonders that would otherwise be inaccessible.