The Hollow Earth is a concept proposing that the planet Earth is entirely hollow or contains a substantial
interior space. Notably suggested by Edmond Halley in the late 17th century, the notion was disproved,
first tentatively by Pierre Bouguer in 1740, then definitively by Charles Hutton in his Schiehallion
experiment around 1774.
It was still occasionally defended through the mid-19th century, notably by John Cleves Symmes Jr. and
Jeremiah N. Reynolds, but by this time it was part of popular pseudoscience and no longer a scientifically
viable hypothesis.
The concept of a hollow Earth still recurs in folklore and as a premise for subterranean fiction, a
subgenre of adventure fiction.
Hypothesis
In ancient times, the concept of a subterranean land inside the Earth appeared in mythology, folklore
and legends. The idea of subterranean realms seemed arguable, and became intertwined with the
concept of "places" of origin or afterlife, such as the Greek underworld, the Nordic Svartálfaheimr, the
Christian Hell, and the Jewish Sheol . The idea of a subterranean realm is also mentioned in Tibetan
Buddhist belief. According to one story from Tibetan Buddhist tradition, there is an ancient city called
Shamballa which is located inside the Earth. In Thracian and Dacian legends, it is said that there are
caverns occupied by an ancient god called Zalmoxis. In Mesopotamian religion there is a story of a man
who, after traveling through the darkness of a tunnel in the mountain of "Mashu", entered a
subterranean garden.
In Celtic mythology there is a legend of a cave called "Cruachan", also known as "Ireland's gate to Hell",
a mythical and ancient cave from which according to legend strange creatures would emerge and be
seen on the surface of the Earth. There are also stories of medieval knights and saints who went on
pilgrimages to a cave located in Station Island, County Donegal in Ireland, where they made journeys
inside the Earth into a place of purgatory. In County Down, Northern Ireland there is a myth which says
tunnels lead to the land of the subterranean Tuatha Dé Danann, a group of people who are believed to
have introduced Druidism to Ireland, and then went back underground.
In Hindu mythology, the underworld is referred to as Patala. In the Bengali version of the Hindu epic
Ramayana, it has been depicted how Rama and Lakshmana were taken by the king of the underworld
Ahiravan, brother of the demon king Ravana. Later on they were rescued by Hanuman. The Angami
Naga tribes of India claim that their ancestors emerged in ancient times from a subterranean land inside
the Earth. The Taino from Cuba believe their ancestors emerged in ancient times from two caves in a
mountain underground.
Natives of the Trobriand Islands believe that their ancestors had come from a subterranean land
through a cavern hole called "Obukula". Mexican folklore also tells of a cave in a mountain five miles
south of Ojinaga, and that Mexico is possessed by devilish creatures who came from inside the Earth.
In the middle ages, an ancient German myth held that some mountains located between Eisenach and
Gotha hold a portal to the inner Earth. A Russian legend says the Samoyeds, an ancient Siberian tribe,
traveled to a cavern city to live inside the Earth. The Italian writer Dante describes a hollow earth in his
well-known 14th-century work Inferno, in which the fall of Lucifer from heaven caused an enormous
funnel to appear in a previously solid and spherical earth, as well as an enormous mountain opposite it,
"Purgatory".
In Native American mythology, it is said that the ancestors of the Mandan people in ancient times
emerged from a subterranean land through a cave at the north side of the Missouri River. There is also a
tale about a tunnel in the San Carlos Apache Indian Reservation in Arizona near Cedar Creek which is
said to lead inside the Earth to a land inhabited by a mysterious tribe. It is also the belief of the tribes of
the Iroquois that their ancient ancestors emerged from a subterranean world inside the Earth. The
elders of the Hopi people believe that a Sipapu entrance in the Grand Canyon exists which leads to the
underworld.
Brazilian Indians, who live alongside the Parima River in Brazil, claim that their forefathers emerged in
ancient times from an underground land, and that many of their ancestors still remained inside the
Earth. Ancestors of the Inca supposedly came from caves which are located east of Cuzco, Peru.
16th to 18th centuries
The following lines from Act 3, Scene 2 of Shakespeare's play A Midsummer Night's Dream, written in
London in 1595/6, suggest that the idea may have been known in Western Europe 100 years before it
took on a more scientific form:
The notion was further popularized by Athanasius Kircher's non-fiction Mundus Subterraneus, who
speculated that there is an "intricate system of cavities and a channel of water connecting the poles".
Edmond Halley in 1692 conjectured that the Earth might consist of a hollow shell about thick, two inner
concentric shells and an innermost core. Atmospheres separate these shells, and each shell has its own
magnetic poles. The spheres rotate at different speeds. Halley proposed this scheme in order to explain
anomalous compass readings. He envisaged the atmosphere inside as luminous and speculated that
escaping gas caused the Aurora Borealis.
Le Clerc Milfort in 1781 led a journey with hundreds of Creek Indians to a series of caverns near the Red
River above the junction of the Mississippi River. According to Milfort the original Creek Indian ancestors
are believed to have emerged out to the surface of the Earth in ancient times from the caverns. Milfort
also claimed the caverns they saw "could easily contain 15,000 – 20,000 families."
19th century
In 1818, John Cleves Symmes, Jr. suggested that the Earth consisted of a hollow shell about thick, with
openings about across at both poles with 4 inner shells each open at the poles. Symmes became the
most famous of the early Hollow Earth proponents, and Hamilton, Ohio even has a monument to him
and his ideas. He proposed making an expedition to the North Pole hole, thanks to efforts of one of his
followers, James McBride.
Jeremiah Reynolds also delivered lectures on the "Hollow Earth" and argued for an expedition. Reynolds
went on an expedition to Antarctica himself but missed joining the Great U.S. Exploring Expedition of
1838–1842, even though that venture was a result of his agitation.
Though Symmes himself never wrote a book about his ideas, several authors published works discussing
his ideas. McBride wrote Symmes' Theory of Concentric Spheres in 1826. It appears that Reynolds has an
article that appeared as a separate booklet in 1827: Remarks of Symmes' Theory Which Appeared in the
American Quarterly Review. In 1868, a professor W.F. Lyons published The Hollow Globe which put forth
a Symmes-like Hollow Earth hypothesis, but failed to mention Symmes himself. Symmes's son Americus
then published The Symmes' Theory of Concentric Spheres in 1878 to set the record straight.
Sir John Leslie proposed a hollow Earth in his 1829 Elements of Natural Philosophy .
In 1864, in Journey to the Center of the Earth Jules Verne describes a hollow Earth containing two
rotating binary stars, named Pluto and Proserpine.
William Fairfield Warren, in his book Paradise Found–The Cradle of the Human Race at the North Pole,
presented his belief that humanity originated on a continent in the Arctic called Hyperborea. This
influenced some early Hollow Earth proponents. According to Marshall Gardner, both the Eskimo and
Mongolian peoples had come from the interior of the Earth through an entrance at the North pole.
20th century